Hi, I've done a lot of work on this topic for the VoronDesign team. A couple of things I'd like to point out: Duct design goes hand in hand with fan selection. The best duct for CPAP won't work well driven by a pair of 4010's. For fan supplied ducts you really need to pay attention to the ratio of surface area to volume, for pressure loss considerations. The fundamentals of cooling don't depend on the number of outlets, it depends on heat transfer. Heat transfer depends on the Nusselt number of the air against the extrudate as it cools below glass temp. Nusselt depends on Reynolds number and Prandtl number. Reynolds number depends on air velocity. so our key will be in maximizing velocity in the area near the nozzle. Horizontally opposed ducts create stagnant zones as the airflow runs into each other. these zones have low velocity and should be avoided. Likewise the vortex idea should be discarded. A vortex around the nozzle woud mean 0 velocity at the nozzle, and that is not great for cooling. It's great that you used test prints to study this. At VoronDesign, we have used a number of tests for this at Voron Design. We currently use a sub 6 minute print for measuring cooling performance at speed, called the D85 Shuriken. Please feel free to contact me (Badnoob of Voron) on our discord for more details. Update: Chirpy of Voron has published a great guide on testing cooling, including the shuriken test, here: github.com/chirpy2605/voron/tree/e32765621ba7ec412bbd1ec42bba24c48e303573/general/Duct_Testing
> these zones have low velocity and should be avoided. Likewize the vortex idea should be discarded. My mental model, and I'm no expert and did no testing, is that since the nozzle is moving rather fast, the just-printed filament is almost immediately in the moving air zone in the vortex. Depending on the shape of what you print. The upside of the vortex seems to be that the nozzle itself isn't cooled so much, so then the temp difference between going out of the nozzle and reaching the vortex is greater. I have no idea if this is good or bad.
I get zero results when searching around for D85 Shuriken. Is this a Discord exclusive file? I have made some improvements to the Mini Stealth cooling ducts (dual 4010 blowers) but would really like to be able to do some more standardized empirical tests.
Yesss seriously awesome. I'm surprised there hasn't been more friendly competition to do something like this in the 3D printing upgrade space in general.
@@MAJ_T_Bagger Same! I started watching with the air cooled water cooler videos and then when the fan showdown started I was like oh heck yes this is it. 😂
It would be sick to see you print with smoke or fog of some kind blowing out so we can see the real relationship between the nozzle and the flow. Also, if you build a raised glass bed with 45-degree mirror under - we could look directly from below at initial layers. Nobody on YT has done this to illustrate a point that I know of. Your content is outstanding.
I've been working on designing a highly efficient duct for my printer for quite some time. Although most of my designs have been lackluster, I've discovered some useful insights: It's more effective to point the ducts slightly below the nozzle, concentrating the airflow more on the part. Additionally, angling the ducts downwards slightly ensures the cooling isn't too strong on the nozzle, preventing temperature fluctuations and reducing the risk of a thermal runaway error. If you opt for horizontal twin ducts, ensure they are either offset from each other (not exactly mirrored) to minimize turbulence or angle them slightly so that when the airstreams meet, they push each other in the same direction, exhausting the air out of the way (a technique I learned from Hero Me ducts). Regarding the shape, most ducts I've seen are rectangular, exhausting the airstream like a thin curtain. However, the downward-angled ones tend to be more rounded. While I'm not entirely sure of the implications of these shape decisions, the rounded shape might provide some benefits.
Beautiful, thank you for this info! I have the follow up video in the works and these ideas will be super useful. I'd like to find a way to visualize the differences using smoke in the next video too. The water test is nice, but it's not a great representation of what really happens and the more I think about it, the less I believe that air coming down is good. It may be good for some parts, it seems to be a better idea to have it come across the surface in a stream of cool air which can quickly warm up and then easily leave.
Nice! A lot of this follows what I've been discussing and theorizing with Mike and others. We gotta get to the bottom of best cooling as a community! There are so many bad designs out there.
@@NeedItMakeIt I'm curious to see the results of the smoke test and hope they will be visible despite the high speed, which might make it challenging. The closest way to visualize how the air will travel is through CFD (Computational Fluid Dynamics) simulations. Unfortunately, I don't have the resources to learn both a simulation environment and the underlying physics, but I believe this is the "right" approach. Ideally, you would perform calculations to determine the desired outcomes (such as airflow path, velocity, turbulence, etc.), then model the duct based on those calculations, followed by simulations, testing, and refining the design. I'm looking forward to your next video and seeing what you've discovered. It seems that, apart from a few videos, there's a significant lack of information on this topic. Also, I'm starting to think that 100% fan speed may not necessarily be the best setting, even for bridging and overhangs, I am curios what is your take on this matter.
I just started my journey on making a custom duct too. I have noticed Voron design also have this thin duct that are directed out of the way (like you mentioned) instead of facing each other like most ducts. The CFD looks promising as well.
@@shababhsiddique Yes but, as far as I know, the Voron ducts are made for printing with ABS/ASA for wich cooling is not that important so for materials such as PLA or geometries that require intensive cooling the Voron ducts might not cut it. I borrowed the cooling duct design from the EVA 3 toolhead and so far it has been solid
Thanks for starting a conversation on duct design. Duct design is much more then number of ducts and where they are pointed. Things like how sharp the bends are in the duct, consistency of the duct cross section area and shape of outlet. This is a pretty deep rabbit hole
Three definitely makes the most sense because it's not dividing the air so much that each port doesn't have much force, but there's still enough ports to create good distribution; interested to see how the other design ideas you mentioned will fair (would be nice if someone with a program that could analyze air flow could test as well, but nothing beats the real world tests)
First off thank you for this video. I think we need to remember that manufacturers are all about sales and not really that much about innovation. let's be honest it's all about best bang for your buck and spending money on research is counterproductive in terms of that goal. I used to come on to these videos looking for quick answers. When I first started out 3D printing I probably would have been disappointed with the results of this testing. Now we're I have been doing this so long I think a video that answers some questions and then asks more is great for the community. The testing with water below the nozzle to check to see if there's a perfect circular vortex right underneath the nozzle is inherently flawed. Especially given the fact that you're looking for the most flow when printing overhangs. Adding smoke would help. Adding different colored smoke to each of the different vents wouldn't be easy but that would help even more. Finding a way to somehow make first the direction of the vents adjustable and then the size and the shape adjustable would also help.
I just love these types of videos, as an engineer I'm always interested to see people testing stuff to see if it can be improved or just to see if it's actually doing what it's supposed to, great work dude keep em coming I'm a big fan of your Chanel 👊💥
That's awesome. And we're going to take it quite a bit further to see if we can come up with the ultimate solution which can then be applied to all 3D printers new and old. I have a few follow up videos in the works to test some ideas and I also want to see what people can send me to test. I'm sure there are some people out there with some very innovative ideas. At the moment, I'm running some tests to understand the problem better and then we can figure out the right solution to apply. It's an interesting subject that I think deserves some attention!
I'm going to give the 2 ducts another go and we'll do a head to head, one like you suggest and the other is the original tested in this video. I think it's going to have a huge impact. I also need to do some smoke testing or something visual to see what's really happening.
After hearing duct so many times it just started to sound like duck. 🦆🦆🦆 cooling was supreme! It is pretty fascinating how visibly different the results can be. I think a lot of our theorizing is validated with these tests. I wonder why the manufacturers settle on the designs they do. Probably has a lot to do with ease of manufacture and lack of complexity. That's why we can print our own parts though! We get to improve what they won't based on business factors. These are some of the best and coolest cooling designs I have seen, even if the T1 makes it a bit easier to integrate. I'm definitely happy to watch more experimenting and testing! A showdown would be great.
...And now I need to do test prints to figure out how to orient bridges and overhangs for best results on my printer, hadn't thought of that. Thanks for another great video!
Awesome! It's a bit of a journey but it's fun to explore these ideas and hopefully we can come up with something that everyone can use in the end! I'm working on follow up videos right now, and I'll see if I can ramp it up a bit and include some smoke testing or something to be able to visualize exactly what's happening.
FANtastic testing! In addition to the bridging behavior I suggest you also include test samples for layer adhesion. Those two attributes are often in competition and it would be unfortunate to perfect bridging behavior but have an overall weak part. Of course that's also impacted by your slicer settings. Lots of opportunities for testing!
Hi, it appears you've overlooked a critical aspect. In fluid mechanics, the presence of two unbalanced outputs can induce a phenomenon known as the vortex effect, like you reproduced with your 3 outputs, but 2 outputs are quite enough to create the vortex. This can often result in greater efficiency than the fan's output alone. The two vents you observe near the outputs may well function as Venturi intakes, designed to enhance the airflow. There exists a plethora of techniques to augment air flow, far more pertinent than merely increasing the number of outputs. One must also consider the internal resistance within the conduit, likely exacerbated by stratified layers and a rough surface texture, which invariably impedes the flow. Additionally, an analysis of the pressure dynamics within the duct conduits is essential, as variations in pressure can significantly diminish the airflow. To further refine your design, you can utilize the fluid simulator available in your CAD software to analyze these factors prior to prototyping. This allows for a detailed examination of the airflow dynamics and helps in optimizing the system's efficiency. Fluid mechanics, as a discipline, is profoundly intricate and necessitates a comprehensive understanding of these multifaceted interactions.
Vortices will only be to the detriment of air cooling design. The air velocity at the center of a vortex is exactly zero. And the velocity decreased as you get closer. The aim is to try to get to force convective cooling where by you are getting you heat transfer coefficient into the 10-15+ range. To do this you will need to maximize velocity and thereby reynolds number, In effect the highly turbulent flow will have micro vortices (1000x smaller than the ones you are mentioning) that act like miniature heat scrubbers buy absorbing some heat and rolling out of the way of the next cooler vortex to do the same. Large static vortices where all the action is happening in the center of the cooling apparatus is going to have the the opposite effect of what you are looking to create.
@@JaredBrewerAerospace I agree with everything you said. However, you forgot that the printhead is never stationary. You don't want to cool down the nozzle itself, which is the thing in the eye of the vortex, but rather the most recent deposit. That’s why using a vortex is perfect for this application.😉
I'm intrigued by offsetting the ducts. It makes it a lot more difficult to design it tho. What I learned from another video is that sharp corners aren't that big of a deal but if there are no knicks and the flow area stays stable (no rapid decreases in area).
Another great video. Thank you! I have also designed a similar duct. I call it Countercurrent Exchange duct. The two air streams pass each other much like cars on a highway. I am very happy with this arrangement.
I can certainly do that. I also wondered why the AUX fans don't direct the air better towards the part. The movement of the printer could guide a duct to move in the Y axis to do a better job of directing the air as well. It might be overkill, but something that could be interesting to explore as well.
I definitely support you testing some of those other hypotheses you have on the duct design. I realize that could be a *series* of videos but even just testing the vortex vs turbulent designs seems like it could make quite a difference
There are more to come for sure, I have some pretty...let's say unique designs coming that I want to test! What I'd love to do is print some large scale models and then run some smoke tests on them to be able to see what's happening. I don't know the best way to do a smoke test yet though.
A very extensive set of tests there dude, I really appreciate how much effort you have put in to explore this topic, great video and a such a pleasant presentation to listen to, all the best from England, 8-bit.
Thank you so much, that means a lot! I hope to do even better on future videos, I have a bit of a series coming for this topic to explore it further too, with the goal of coming up with a more universal solution for all printers. I've made some progress since the video in creating a slightly better solution, and I also want to see what everyone else can come up with for a bit of a friendly competition.
Thanks for doing these tests. I've been wondering about this subject for a while. One suggestion for future videos. You may want to have a ring light around the camera, or a soft box pointing at you from really close to the camera. Your eyes are very dimly lit in this video. The last time I priced LED ring lights, you could get a good enough one for $45-$65. Not sure if they are still that cheap though. You could also just point a bright light at a big sheet of poster board or anything white, to bounce a soft light to fill in the shadows over your eyes. It's just a bit more work to get it set up than with a ring light on a stand. Keep up the great work! Your channel is growing much faster than most other channels under 100K. I'd bet you'll be past 100K by the end of this year.
Tried this a few years ago and found offsetting the ducts away from the nozzle works best. However there are better designs out there currently such as the Hevort Tentacool CPAP duct.
This testing is so cool (pun intended) and under explored, a notion that can also improve airflow is the "Venturi effect", but setting up that kind of duct might be a little tricky.
Having thin air ducts facing away technically is leaning towards the "sticky air multiplier" theory, where fast moving air will not act as a perfect column of air, but rather accelerate the air around the path as well. This could promote airflow over the part by creating a mini vacuum, but it's very undeveloped in that scenario
Cool informative content as always. Have you considered visiting the BerdAir concept or ducting outlet configurations. The BerdAir is focused on pressure rather than volume of air from memory. Airflow is focused below the nozzle at the part, offset from each other to minimise interference. There are existing STL /Jigs designs available on Thingiverse and Printables which you could leverage.
Thanks! I'm going to have a look, I want to make a bit of a competition out of this to see if we can come up with the best solution and then we can apply that solution to all of the common printers out there.
Awesome video I have been messing with this kind of thing on and off for a couple years. 3 ducts has been the best for me so far, I have tested with off sets and all kinds of shapes, sizes and angles. I am excited for more tests. You are much better at Fusion360 than I.
Amazing video. Hopefully, someone will design one for the k1 series soon and put this much thought and effort into the design. Again great video and would like to see you do this kind of thing for more printers. It is nice to see your thought process etc. Cheers 🇨🇦
Try the vortex 3 duct one, but with one of the side ones removed. Then you have 2 making a vortex that doesn’t have resistance on one side. This might make it push the hot air off more effectively. I’m also curious what would happen if you took the fan and reversed it and PULLED the air out. Sucking air out tends to cool better than pushing air in when it comes to rooms, so what about here?
I think it would be interesting to make it similar to the Flat jet air nozzles from lechler. For me the number of flow is not really important but a well guided and a good released gaz is much more effective. Good work as always
I really enjoyed this video because I feel like part cooling ducts stand to have a lot of improvement. I would be extremely interested in a video solely on the CAD side of creating these ducts, it’s something I’ve always struggled with
minimum 2, maximum 2.. that works best for me 😊. Hit it at a shearing angle. I only play with air flow rate using 12v radial fan for a 24v system😊. Setting slicers at 50% max and flip to 75 o 100 at very small portion of prints during bridging or critical cooling section.❤love it so far.
Nice! I just experimented again with 2 today, and unfortunately I found that the option with 6 ducted version I designed yesterday performed significantly better. A little less air coming from all sides vs lots of air coming from only 2 side may be part of the reason. I have to do more testing and also try to see if I can do a smoke test of some kind as well. ideally I'd have an IR camera for this testing, I'll have to see if I can get my hands on one somehow.
Thank you so much! It is absolutely my pleasure, I have a lot more ideas like this and I have the follow up video already in the works for next weekend. I'd like to show everyone how to do this themselves because it was really hard at first, but now after doing this quite a few times, it's easy and there are a few really important things that can save you hours of frustration.
I think it is important to focus on cooling the part, as this is in-fact the part cooling fan! Pointing the duct more towards the printed object just makes sense.
As you keep adding ducts it has me wondering at what point is a torus style duct better? The type that would surround the hotend 360* and exit through a slot that faces the nozzle. You may end up going off the deep end learning fluid dynamics to solve this problem!
a design that you see a lot as well is the circular fan duct. i would love to see all of these ducts improved with those points you mentioned and see a second video on this topic. because i was trying to find a good fan duct for my printer as well!
Circular is a good option, I'd have to see what happens with that idea. I've mainly been using longer thinner rectangular openings. I have at least 2 more videos coming on this subject and I'll include some smoke testing of some kind as well to really get an idea of what's happening with them. I'd like to end up with a result that we can apply to any 3D printer and have better results than anything else out there.
@@NeedItMakeIt I was just about to refer you to a great video a creator did on air amplifier ducting then realised it was one of yours. Taking the suggestions from @HerrickAaron in an earlier reply it would seem maximising velocity of airflow is key. I now presume that video was deliberately related to improving hot end fan ducting. I do wonder how it could be directed at the extrudate rather than down and around the whole nozzle.
Stock K3 cooling offsets the two fans and that works quite well. However that’s two fans with very little ducting, the fans are pointing pretty much straight at the nozzle with some small nozzles attached to the output
Great video! One note. Your air should be cooling the part right below the nozzle, not the nozzle itself. The goal is to cool the filament as it is being extruded onto the layer. Cooling the nozzle isnt recommended as you generally want the nozzle to be as hot as it can be. You want the filament to extrude at the right adhesion temp, then cooled immediately to help prevent overheating / warping of that area on the part.
100% I agree with that. I've seen that the stock duct cools the nozzle far too much, and the single and double options I've created do as well, the others which are set off to a slight angle seem to do better, but I'd need to find a way to test this to see how much heater struggles to keep up. I really need an IR camera! I could design a version which places the air very precisely to test your idea.
Would've loved to see this done on more common printers like the A1 series. Also, will be nice to see the water test with the airflow for each duct on future videos. Great job as always.
Very timely video for me, and I hope it creates lots of discussion about the best duct design 😊 I am currently designing a toolhead for the Creality K1 family of printers that use standard revo hot-end parts (revo voron) support several of the extruder models out there, and most related to this, a rear mounted part cooling fan so need to find a good duct design for that :) as always great video and information..
I started working on the video last night to show how this is done, and of course we're going to have to take it to the next level as well and test that version out too. It should be a good one!
In terms of "path" the bend should be contiously differentiable twice so there is no "sharp" corner both in terms of direction and velocity(change) and short as possible so there is no loss
If we can get away with the double duct and have them offset to the side of the nozzle I think it's possible. I'd imagine that the long corrugated hose leading to the duct will cause quite a lot of loss also, I wonder whether a more flexible and smoother silicone hose would be better. Maybe for the next tests I need to use 2 printers, one with the CPAP and one with a standard blower style part fan.
Will be interesting to see the difference as ratio between inlet and the outlets will play a role too. Advantage of the CPAP is probably that it will be more "laminar" than a 5015 closely mounted to the ducting system(more equal pressure/flow across the inlet"). I am looking forward to the results. The fan showdown series by major hardware is fun to follow and hope we get some fun out of this as well
I've always assumed you want the air flow to not hit the nozzle, but to hit the plastic directly beneath where the nozzle is. and so I would assume you want an air flow angle that is the same as the angle on the bottom of your nozzle and you want them as consistent as possible all the way around. So whichever direction the head is moving, it will be blowing cold air onto the part right behind.(I have a Cheap delta printer that has really bad cooling performance, so I put a really big fan on it and it was blowing on the nozzle too much and cooling it off So I was getting nozzle jams)
You want the part to be just cool enough to support the layer above. The hotter the part, the stronger layer adhesion. Heated chamber prevents overcooling. You can also passively cool, by printing many objects on the build plate. This allows the parts to gradually cool down without the need for a cooling fan. It is a balancing act especially if you bring cold air from outside the heated chamber.
That's a tough one, when printing with ABS, I print much slower and with almost no part cooling on, with PLA, we're talking more extreme speeds and much more cooling. I think it's a good topic to explore more, when "cooling" in a heated chamber, the air is going to be fairly warm so it cannot extract as much heat, in the case of these materials, it may be a good thing to make sure that the ABS or PC parts don't warp and shrink too much during the print.
I have at least 2 more planned already, I wanted to show how to make one yourself and then print and test that version and then I also want to explore the double version with offset ports and then we can go from there.
Always had trouble printing dimensionally accurate small gears for the differential in 3d printed truggy by open RC. I put it down to inadequate cooling as some teeth in the circle curled up. Would be interesting to see how your designs handle that. Also just watched a video by Nathan Builds Robots about glass and carbon fibers in filament. You might not want to handle your glass fiber ABS with your hands anymore and make sure you have an air fillter running when printing with it. Can't wait to see the next video!
I'll find the gear and see if I can print it! Which filament do you use? For sure, that's a good topic he's on, I agree that we don't speak much about the long term health impacts of 3D printing. Coming from a Woodworking background, it's similar, except some of the particles are known carcinogens, specifically from hardwood lumber dust. It would probably be best to have a Room filtration system active at all times especially if you're working near your printer.
@@NeedItMakeIt For the small gears I was using ABS+. In the end I went with metal gears in the differential as it was cheap and I had other things I had to fix. If I were to try it again I would use Poly Carbonate as it is super strong, temperature resistant and cheap for its properties. A lot of engineering filaments get pricey quickly. I do really like my carbon fiber PC filament because it is way easier to print with. The fiber breaks up the polymer chains causing less shrinkage. The only downside is that the layer adhesion isn’t as good as straight PC. Don’t get me wrong, those parts are still really strong. I use the Carbon Fiber PC for my hotend fan ducts because it is light and doesn’t deform on my Prusa mk3s. Which I had ABS+ deform on me enough to start knocking prints. I voted for the three ducts with the vortex, it was only a guess though. Nice to see it work.
You mentioned doing a new duct for the Qidi Q1 Pro. Was wondering if you have any designs for that and/or are planning a video for that printer like you've done for this flsun one? Would be very interested in improving the cooling on the Qidi Q1 Pro!
I'd love to do an option for every popular printer, including the Q1 Pro. Before that I was hoping to get some ideas from the community to test out and then we can come up with the best possible option together.
Hey dude, Based on this video and your experience of the panda jet, I think a 3 or 4 duct design once you have the knowledge on offset positioning, duct sizes etc. On the Q1 (And other Qidi printers), the probe is on the right and mounts for beacon or Carto place it behind the nozzle. Placement of a 4 duct design maybe best at 45 degrees, 135 degrees, 225 degrees and 315 degrees. For a 3 duct design at 45 degrees, 165 degrees and 285 degrees. Those as the positions least likely to interfere with either probes but I guess that would be in the design work. I also wonder whether the stock fan on the Qidi (with it's non-standard design) would be better or if it would be better to consider a fan swap with new duct design for Qidi printers?
Ive seen visible print quality improvement in all my printers when installing community designed shrouds. Especially on printers where I can go from one cooling duct to three. It makes a huge difference. In the same vein, these enclosed corexy printers like the K1 make no sense with the single giant aux fan on only one side of the print bed.
Great content! Get sponsored by one of the meal services that ships with dry ice, so you can use it to visualize where the air is going in each design. A little dry ice + boiling water makes a nice print bed full of mist.
Great video! This kind of testing is so interesting to me. It makes me wonder why the OEM can't do this and have 3d printable improved duct files available for people who want them. Saves them the injection molding costs, but provides a much better result to the customer.
Thanks! I think it's an area that needs a bit more attention for sure. I think at a minimum they could provide a file that could be printed at home. I think you're right, it comes down to cost and to some extent the look. I really like the open and somewhat organic look, but some people probably prefer the clean condensed version.
One caveat that I noticed early on (2019?) with different ducts is that the best bridging often happened when the fan cooled the nozzle... In other words, lowering filament temperature. It made it hard to find the actual best ducts because the "best" weren't the best
Hello, I own my 3D printing compagny since 8 years : Zoltan3D. I already tried how much cooling is great ... your tests in quality are nice ... but you forgot the most important part in this test !!!! Yes, it's greater in overhang, but the prints become weaker with too much cooling because you don't let time to the filament to stick on the previous layer ! So yes, it can look cool, it's okay for a decorative object ... but it's WAYYY weaker with technical parts with too much cooling
@@NeedItMakeIt Without CFD simulation this is unfortunately not very easy and even with it you often have to test new prototypes. The round profile is definitely the best to avoid pressure drop as it has the least edge friction. It also has the least turbulence, although the question is whether turbulence is good or bad in this application. Using the same inlet and outlet area for the three nozzles is important in any case, this is based on the flow law. To avoid pressure differences on the sections, the ratio of the length L to the flow area A should be as constant as possible (L/A). You could also use larger nozzles which would reduce the outlet velocity. Slower velocities are also more laminar and can be improved with a grid of fine tubes. I'm really looking forward to seeing what else you come up with. There are so many possibilities :D
can you get the part number off the c-pap blower so we can find a data sheet and the size of the tubing it's using i want to do some detailed CFD on mine and optimize for an apx flow
I wonder if overhangs and bridges close to the bed get impacts from "ground effect". As opposed to similar features a few inches up, which wouldn't see any reflected airflow.
For my own DIY built 3d printer, I have the nozzle surrounded by a circle shaped duct. It actively touches the silicone boot of the nozzle. I have no idea how it compares to a more typical design, but I get pretty epic bridges out of it.
I've seen a few of these and I think they can work really well, it'll have to be tested against some of the other designs. the 360 surrounding version would need to be balanced out a bit better with larger and smaller ports, but it's doable for sure!
10:33 I would venture a guess that these small ports are to prevent excess static pressure. Also curious, depending on design, if these ports might actually suck IN air at lower flow rates.
I like the ideas for further testing, small tweaks lile duct shape. I would say though it always best to figure out a objective way to measure the results.
More are coming and we'll dial the testing in better as well! I'd also like to add smoke testing of some kind, in order to make educated decisions, we need to understand what's happening during a real print. A simulation is possible, but it's not going to provide much info about what's happening during the testing. I also wonder whether an IR camera would provide the info we need.
I would like to see you do a video that covers venting a printer to a window etc.. it is confusing for many with the pressure changes.. inline fans.. enclosures over enclosures.. directly from the printer exhaust.. from the top of the printer..I would love to print in materials like ASA but I want to vent the fumes..
you could make an "infinity duct" wrapping all around the nozzle in a torus, perhaps with the exit slot angled downards. thinking about it more this would basically be an "aerospike" cooler
I think the "relief ports" on that one duct are to cool the part aswell. When printing really fast, the nozzl will not spend enough time near the recently laid down filament. That's why you have auxillary bed cooling fans on the bambu x1 and voron 0.2. This would be similar to having an auxillary bed-widevcooling fan.
It could be, i guess I'd need to cover them up to see if there is any noticeable impact. I'm not certain that a CPAP can really replace one or two auxiliary fans, but I'd like to at least try. Having a part fan that can cool locally and also cool the rest of the part is a tall order.
Great content again!👍Very interesting topic too. Im guessing that downward facing ducts along the nozzle would warm and cool larger surface area of the print below. If pointed along the printing plane same would apply more along the top layers of the print. Which one is better might depends on the geometry are you printing.
Thank you! I think so too, there seems to be a lot left to explore on this and with some really fast printers coming out I think we're going to need exceptional cooling. The AUX fan is a good option, but I've found that if it only comes from one side, the results are only good on one side. I think it'd be good to dive in a bit deeper and really find out what makes for a good print and then we can design a duct for any printer using that same solution. I have a video coming soon where we look at the angle, whether horizontal is better or more vertical, also the position of the air related to the center of the nozzle laterally. You make a good point about the print itself affecting the results too. Some prints with infill will cool differently, and some infills also allow air to circulate better, which could also have an impact. Interesting stuff!
@@NeedItMakeIt i personally print alot of pla but also higher temperature materials in which you need very little or no cooling in order to have good layer adhesion and no warping. In these cases heat should be distributed more evenly and prevent early cooling. Maybe for a good overall solution the cooling should be relatively even in directions along the printing plane. And how about suckin air away from the part?
YES! I will make a better duct for every single common printer if I can. Maybe I should release a poll and then we can decide which to do first. The QIDI is still one of my favorite printers, especially for high-temp materials so it's going to be a good one to upgrade a bit more. What I'd like to do is take a bit more time to experiment so that we have the absolute best option. I'm also sending out a challenge to anyone who can do better and we'll have a face-off, my best vs anyone else's and the winner will receive a prize as well. I'll release a video on that subject so we can get some contest rules, but it should be fun and the result will be something even better I'm sure. Nothing like a bit of competition to drive innovation.
I've always wondered how the hell people design these things. Seems like a lot of really hard work, because they're so curvy and complex in their shape. Never had any clue how to do that in any CAD program.
I think I'll have to create a mold and make one from some HT silicone! I agree, I also think the nozzle should be replaced with the CHT setup to get a little extra flow. There is a little problem with doing it because there is also a triple ported design inside the heater block, if those three don't line up with the three in the CHT, it could be a problem. Only one way to find out!
I think there's too much looking at symmetrical design, besides the vortex. However, the vortex does try to create a circle of air. I think you should try the tri-duct vortex but with only two ducts, that way some fresh air gets pulled in from the gap where the third duct was so you don't create a insulating air layer. Purely an opinion with no experience using FDM printers.
This is a good idea, I have the 2 offset duct test coming in the video I'll be releasing this weekend! I will also be adding some smoke and water testing for future testing videos to really understand what's happening with the air during a print.
I'd like to have something for the Q1, the K1, the X1/P1, A1, and really anything else out there that could use an upgrade. I want to take a bit more time to really dial this in and get a good understanding of what produces the best results and then we can create a solution for every printer out there that needs one.
Looking at the fan in the q1 pro you can get higher output fans. But im seeing the outlet is smaller in size then the stock. We would need a smaller inlet to the parts cooler. I suck at 3d software though lol
Absolutely, the AUX fans are another good option as long as they are on both sides, I've found that printers with only one have poor results on one side and good on the other.
Sometimes relief holes in a duct actually increase the speed of air inside the duct. It's why many air chucks have a hole in the side. If you remove that hole or cover it up, you can immediately see a noticeable drop in air speed. I'm not sure about those ducts specifically, but that's just a guess from other kinds of ducts I've seen in the past. (Edit, air passing across the inner surface of the holes can cause a vacuum, pulling air into the holes and greatly increasing the output/efficiency of the duct).
Very interesting, thanks for that information, it's certainly something to try, creating a venturi effect of sorts? I'd need some way of measuring wind speed at a very small scale to test this myself.
What type of air chuck are you referring to? Tire filling chuck? Air chuck on a lathe? or something else? Because in my mind I immediately thought of the blower attachment that goes on compressor hoses, for clearing away debris or drying off your workpiece. In this case, the hole in the nozzle is there for safety reasons. It is there to provide an alternate route for the pressurized air to escape in the event the nozzle comes in contact with someone's skin. Thus preventing a horrible kind of injury that makes my skin crawl just thinking about it. These are also not technically air chucks, which is why I think you may be referring to something else entirely.
So while having the ducts close to the nozzle seems logical, it depends on the print. Here you are print small objects where the amont of time for the air to do its job is aided by the fact that the nozzle will be back over the area soon. However take a longer print like a dragon or a house that takes up nearly all the bed and the motions are longer. Getting the nozzles too close limits how much time is available for them to cool the filament as the nozzle moves away. The only work around then requires an external source of air which may be obstructed by other parts of the print. Really I think where you had the ducts was good so they aren't impacted by the heater block which could deform things over time depending on the filament used.
I ve designed a 4020 (server fan with 35m³/h) fan duct for my prusa i3 bear and its so powerful that it's cooling the (imho too weak) bed so much till Klippers says the heating failed. However ive chosen 3 ducts and its working great
I would love to see the 3 nozzle one designed for the older ender 3 and ender 5 hotends. or taking the existing Satsana and alter the air path to be off centered.
Hi, I've done a lot of work on this topic for the VoronDesign team.
A couple of things I'd like to point out:
Duct design goes hand in hand with fan selection. The best duct for CPAP won't work well driven by a pair of 4010's. For fan supplied ducts you really need to pay attention to the ratio of surface area to volume, for pressure loss considerations.
The fundamentals of cooling don't depend on the number of outlets, it depends on heat transfer. Heat transfer depends on the Nusselt number of the air against the extrudate as it cools below glass temp. Nusselt depends on Reynolds number and Prandtl number. Reynolds number depends on air velocity. so our key will be in maximizing velocity in the area near the nozzle.
Horizontally opposed ducts create stagnant zones as the airflow runs into each other. these zones have low velocity and should be avoided.
Likewise the vortex idea should be discarded. A vortex around the nozzle woud mean 0 velocity at the nozzle, and that is not great for cooling.
It's great that you used test prints to study this. At VoronDesign, we have used a number of tests for this at Voron Design. We currently use a sub 6 minute print for measuring cooling performance at speed, called the D85 Shuriken. Please feel free to contact me (Badnoob of Voron) on our discord for more details.
Update: Chirpy of Voron has published a great guide on testing cooling, including the shuriken test, here:
github.com/chirpy2605/voron/tree/e32765621ba7ec412bbd1ec42bba24c48e303573/general/Duct_Testing
> these zones have low velocity and should be avoided. Likewize the vortex idea should be discarded.
My mental model, and I'm no expert and did no testing, is that since the nozzle is moving rather fast, the just-printed filament is almost immediately in the moving air zone in the vortex. Depending on the shape of what you print. The upside of the vortex seems to be that the nozzle itself isn't cooled so much, so then the temp difference between going out of the nozzle and reaching the vortex is greater. I have no idea if this is good or bad.
I get zero results when searching around for D85 Shuriken. Is this a Discord exclusive file? I have made some improvements to the Mini Stealth cooling ducts (dual 4010 blowers) but would really like to be able to do some more standardized empirical tests.
@@alanrushing2807 I added a link to Chirpy's discussion of the cooling benchmark test we use, it also has the files. Timing of the tests is key!
@@HerrickAaron Awesome! Thank you!
voron dont use like huge side blower?
the fan showdown of 3d printer cooling is such a cool idea!
I think so! I've also been watching those RC boat propeller test videos, and they're really interesting with some unexpected results too.
A collab with @MajorHardware would be great!
Yesss seriously awesome. I'm surprised there hasn't been more friendly competition to do something like this in the 3D printing upgrade space in general.
@realgoose I see you're a man of culture lol. The fan showdown is surprisingly interesting, been watching since the beginning.
@@MAJ_T_Bagger Same! I started watching with the air cooled water cooler videos and then when the fan showdown started I was like oh heck yes this is it. 😂
It would be sick to see you print with smoke or fog of some kind blowing out so we can see the real relationship between the nozzle and the flow. Also, if you build a raised glass bed with 45-degree mirror under - we could look directly from below at initial layers. Nobody on YT has done this to illustrate a point that I know of. Your content is outstanding.
YES! Oh I like that idea with the mirror, that's very clever.
So... Smoke and mirrors? For once, a totally positive thing. IT MUST BE DONE!
@@NeedItMakeIt I do clever for full time living.
It'd be tricky to setup, but maybe Schlieren photography?
How did you make the part of the ducts that bolts to the effector? Was this the generative design module?
I think for the direction, the ducts should be rated by which has the least bad worst case scenario.
I've been working on designing a highly efficient duct for my printer for quite some time. Although most of my designs have been lackluster, I've discovered some useful insights:
It's more effective to point the ducts slightly below the nozzle, concentrating the airflow more on the part. Additionally, angling the ducts downwards slightly ensures the cooling isn't too strong on the nozzle, preventing temperature fluctuations and reducing the risk of a thermal runaway error.
If you opt for horizontal twin ducts, ensure they are either offset from each other (not exactly mirrored) to minimize turbulence or angle them slightly so that when the airstreams meet, they push each other in the same direction, exhausting the air out of the way (a technique I learned from Hero Me ducts).
Regarding the shape, most ducts I've seen are rectangular, exhausting the airstream like a thin curtain. However, the downward-angled ones tend to be more rounded. While I'm not entirely sure of the implications of these shape decisions, the rounded shape might provide some benefits.
Beautiful, thank you for this info! I have the follow up video in the works and these ideas will be super useful. I'd like to find a way to visualize the differences using smoke in the next video too. The water test is nice, but it's not a great representation of what really happens and the more I think about it, the less I believe that air coming down is good. It may be good for some parts, it seems to be a better idea to have it come across the surface in a stream of cool air which can quickly warm up and then easily leave.
Nice! A lot of this follows what I've been discussing and theorizing with Mike and others. We gotta get to the bottom of best cooling as a community! There are so many bad designs out there.
@@NeedItMakeIt I'm curious to see the results of the smoke test and hope they will be visible despite the high speed, which might make it challenging. The closest way to visualize how the air will travel is through CFD (Computational Fluid Dynamics) simulations. Unfortunately, I don't have the resources to learn both a simulation environment and the underlying physics, but I believe this is the "right" approach. Ideally, you would perform calculations to determine the desired outcomes (such as airflow path, velocity, turbulence, etc.), then model the duct based on those calculations, followed by simulations, testing, and refining the design.
I'm looking forward to your next video and seeing what you've discovered. It seems that, apart from a few videos, there's a significant lack of information on this topic. Also, I'm starting to think that 100% fan speed may not necessarily be the best setting, even for bridging and overhangs, I am curios what is your take on this matter.
I just started my journey on making a custom duct too. I have noticed Voron design also have this thin duct that are directed out of the way (like you mentioned) instead of facing each other like most ducts. The CFD looks promising as well.
@@shababhsiddique Yes but, as far as I know, the Voron ducts are made for printing with ABS/ASA for wich cooling is not that important so for materials such as PLA or geometries that require intensive cooling the Voron ducts might not cut it. I borrowed the cooling duct design from the EVA 3 toolhead and so far it has been solid
Thanks for starting a conversation on duct design.
Duct design is much more then number of ducts and where they are pointed.
Things like how sharp the bends are in the duct, consistency of the duct cross section area and shape of outlet.
This is a pretty deep rabbit hole
Three definitely makes the most sense because it's not dividing the air so much that each port doesn't have much force, but there's still enough ports to create good distribution; interested to see how the other design ideas you mentioned will fair (would be nice if someone with a program that could analyze air flow could test as well, but nothing beats the real world tests)
First off thank you for this video. I think we need to remember that manufacturers are all about sales and not really that much about innovation. let's be honest it's all about best bang for your buck and spending money on research is counterproductive in terms of that goal. I used to come on to these videos looking for quick answers. When I first started out 3D printing I probably would have been disappointed with the results of this testing. Now we're I have been doing this so long I think a video that answers some questions and then asks more is great for the community. The testing with water below the nozzle to check to see if there's a perfect circular vortex right underneath the nozzle is inherently flawed. Especially given the fact that you're looking for the most flow when printing overhangs. Adding smoke would help. Adding different colored smoke to each of the different vents wouldn't be easy but that would help even more.
Finding a way to somehow make first the direction of the vents adjustable and then the size and the shape adjustable would also help.
Wow, man, this video is very interesting - and you are right: it opens more questions. Thanks for such nice investigation!
I just love these types of videos, as an engineer I'm always interested to see people testing stuff to see if it can be improved or just to see if it's actually doing what it's supposed to, great work dude keep em coming I'm a big fan of your Chanel 👊💥
That's awesome. And we're going to take it quite a bit further to see if we can come up with the ultimate solution which can then be applied to all 3D printers new and old. I have a few follow up videos in the works to test some ideas and I also want to see what people can send me to test. I'm sure there are some people out there with some very innovative ideas. At the moment, I'm running some tests to understand the problem better and then we can figure out the right solution to apply. It's an interesting subject that I think deserves some attention!
I think you can try the 2 ducts but point one to the front of the nozzle and the other offset to the back. Great video.
I'm going to give the 2 ducts another go and we'll do a head to head, one like you suggest and the other is the original tested in this video. I think it's going to have a huge impact. I also need to do some smoke testing or something visual to see what's really happening.
After hearing duct so many times it just started to sound like duck. 🦆🦆🦆 cooling was supreme! It is pretty fascinating how visibly different the results can be. I think a lot of our theorizing is validated with these tests. I wonder why the manufacturers settle on the designs they do. Probably has a lot to do with ease of manufacture and lack of complexity. That's why we can print our own parts though! We get to improve what they won't based on business factors. These are some of the best and coolest cooling designs I have seen, even if the T1 makes it a bit easier to integrate. I'm definitely happy to watch more experimenting and testing! A showdown would be great.
...And now I need to do test prints to figure out how to orient bridges and overhangs for best results on my printer, hadn't thought of that. Thanks for another great video!
I like the pace, detail and honestly keep it up man. Videos are a GOOD use of my time!
Awesome! It's a bit of a journey but it's fun to explore these ideas and hopefully we can come up with something that everyone can use in the end! I'm working on follow up videos right now, and I'll see if I can ramp it up a bit and include some smoke testing or something to be able to visualize exactly what's happening.
Nice to see a video of someone getting all their ducts in a row. Rare sight these days!
HAHA, awesome. I will have to work on my pronunciation a bit, it sounded like Duck much more than I was hoping for...
FANtastic testing! In addition to the bridging behavior I suggest you also include test samples for layer adhesion. Those two attributes are often in competition and it would be unfortunate to perfect bridging behavior but have an overall weak part. Of course that's also impacted by your slicer settings. Lots of opportunities for testing!
Hi, it appears you've overlooked a critical aspect. In fluid mechanics, the presence of two unbalanced outputs can induce a phenomenon known as the vortex effect, like you reproduced with your 3 outputs, but 2 outputs are quite enough to create the vortex. This can often result in greater efficiency than the fan's output alone. The two vents you observe near the outputs may well function as Venturi intakes, designed to enhance the airflow.
There exists a plethora of techniques to augment air flow, far more pertinent than merely increasing the number of outputs. One must also consider the internal resistance within the conduit, likely exacerbated by stratified layers and a rough surface texture, which invariably impedes the flow. Additionally, an analysis of the pressure dynamics within the duct conduits is essential, as variations in pressure can significantly diminish the airflow.
To further refine your design, you can utilize the fluid simulator available in your CAD software to analyze these factors prior to prototyping. This allows for a detailed examination of the airflow dynamics and helps in optimizing the system's efficiency.
Fluid mechanics, as a discipline, is profoundly intricate and necessitates a comprehensive understanding of these multifaceted interactions.
Vortices will only be to the detriment of air cooling design. The air velocity at the center of a vortex is exactly zero. And the velocity decreased as you get closer. The aim is to try to get to force convective cooling where by you are getting you heat transfer coefficient into the 10-15+ range. To do this you will need to maximize velocity and thereby reynolds number, In effect the highly turbulent flow will have micro vortices (1000x smaller than the ones you are mentioning) that act like miniature heat scrubbers buy absorbing some heat and rolling out of the way of the next cooler vortex to do the same. Large static vortices where all the action is happening in the center of the cooling apparatus is going to have the the opposite effect of what you are looking to create.
@@JaredBrewerAerospace I agree with everything you said. However, you forgot that the printhead is never stationary. You don't want to cool down the nozzle itself, which is the thing in the eye of the vortex, but rather the most recent deposit. That’s why using a vortex is perfect for this application.😉
I'm intrigued by offsetting the ducts. It makes it a lot more difficult to design it tho. What I learned from another video is that sharp corners aren't that big of a deal but if there are no knicks and the flow area stays stable (no rapid decreases in area).
I have a duct for the biqu H2 hotend that does the vortex thing and it works pretty well
Good idea for testing, with these it seems like there is infinite number of variations to try out 😊
Another great video. Thank you! I have also designed a similar duct. I call it Countercurrent Exchange duct. The two air streams pass each other much like cars on a highway. I am very happy with this arrangement.
Great video! I'd also like to see the effect of a general "chamber" fan just blowing air down to the part in addition to the part cooling
I can certainly do that. I also wondered why the AUX fans don't direct the air better towards the part. The movement of the printer could guide a duct to move in the Y axis to do a better job of directing the air as well. It might be overkill, but something that could be interesting to explore as well.
I definitely support you testing some of those other hypotheses you have on the duct design. I realize that could be a *series* of videos but even just testing the vortex vs turbulent designs seems like it could make quite a difference
There are more to come for sure, I have some pretty...let's say unique designs coming that I want to test! What I'd love to do is print some large scale models and then run some smoke tests on them to be able to see what's happening. I don't know the best way to do a smoke test yet though.
A very extensive set of tests there dude, I really appreciate how much effort you have put in to explore this topic, great video and a such a pleasant presentation to listen to, all the best from England, 8-bit.
Thank you so much, that means a lot! I hope to do even better on future videos, I have a bit of a series coming for this topic to explore it further too, with the goal of coming up with a more universal solution for all printers. I've made some progress since the video in creating a slightly better solution, and I also want to see what everyone else can come up with for a bit of a friendly competition.
Thanks for doing these tests. I've been wondering about this subject for a while.
One suggestion for future videos. You may want to have a ring light around the camera, or a soft box pointing at you from really close to the camera. Your eyes are very dimly lit in this video. The last time I priced LED ring lights, you could get a good enough one for $45-$65. Not sure if they are still that cheap though. You could also just point a bright light at a big sheet of poster board or anything white, to bounce a soft light to fill in the shadows over your eyes. It's just a bit more work to get it set up than with a ring light on a stand.
Keep up the great work! Your channel is growing much faster than most other channels under 100K. I'd bet you'll be past 100K by the end of this year.
Very cool idea of proposing the challenge for a better design! I'm looking forward to finding out the results!
Tried this a few years ago and found offsetting the ducts away from the nozzle works best. However there are better designs out there currently such as the Hevort Tentacool CPAP duct.
This testing is so cool (pun intended) and under explored, a notion that can also improve airflow is the "Venturi effect", but setting up that kind of duct might be a little tricky.
Why stop at 5 ducts? Make one with so many ducts that cthulhu becomes envious.
Having thin air ducts facing away technically is leaning towards the "sticky air multiplier" theory, where fast moving air will not act as a perfect column of air, but rather accelerate the air around the path as well. This could promote airflow over the part by creating a mini vacuum, but it's very undeveloped in that scenario
Cool informative content as always. Have you considered visiting the BerdAir concept or ducting outlet configurations. The BerdAir is focused on pressure rather than volume of air from memory. Airflow is focused below the nozzle at the part, offset from each other to minimise interference. There are existing STL /Jigs designs available on Thingiverse and Printables which you could leverage.
Thanks! I'm going to have a look, I want to make a bit of a competition out of this to see if we can come up with the best solution and then we can apply that solution to all of the common printers out there.
Awesome video I have been messing with this kind of thing on and off for a couple years. 3 ducts has been the best for me so far, I have tested with off sets and all kinds of shapes, sizes and angles. I am excited for more tests. You are much better at Fusion360 than I.
Wow! Fantastic data and super interesting results! Do you think printing the duct(s) in resin would change anything?
Cool study! Great idea to make it accessable for us. You can turn this into a competition!
Amazing video. Hopefully, someone will design one for the k1 series soon and put this much thought and effort into the design. Again great video and would like to see you do this kind of thing for more printers. It is nice to see your thought process etc. Cheers 🇨🇦
Try the vortex 3 duct one, but with one of the side ones removed. Then you have 2 making a vortex that doesn’t have resistance on one side. This might make it push the hot air off more effectively.
I’m also curious what would happen if you took the fan and reversed it and PULLED the air out. Sucking air out tends to cool better than pushing air in when it comes to rooms, so what about here?
I think it would be interesting to make it similar to the Flat jet air nozzles from lechler. For me the number of flow is not really important but a well guided and a good released gaz is much more effective.
Good work as always
I really enjoyed this video because I feel like part cooling ducts stand to have a lot of improvement.
I would be extremely interested in a video solely on the CAD side of creating these ducts, it’s something I’ve always struggled with
So many ducts but not a single goose….great video.
great cooling is underrated
thanks for this video!
I like your channel a lot man keep theses tests they are soo good
minimum 2, maximum 2.. that works best for me 😊. Hit it at a shearing angle.
I only play with air flow rate using 12v radial fan for a 24v system😊. Setting slicers at 50% max and flip to 75 o 100 at very small portion of prints during bridging or critical cooling section.❤love it so far.
Nice! I just experimented again with 2 today, and unfortunately I found that the option with 6 ducted version I designed yesterday performed significantly better. A little less air coming from all sides vs lots of air coming from only 2 side may be part of the reason. I have to do more testing and also try to see if I can do a smoke test of some kind as well. ideally I'd have an IR camera for this testing, I'll have to see if I can get my hands on one somehow.
Great video.
Impressive designs
Thanks 🎉for sharing your expirence with all of us 😀
Thank you so much! It is absolutely my pleasure, I have a lot more ideas like this and I have the follow up video already in the works for next weekend. I'd like to show everyone how to do this themselves because it was really hard at first, but now after doing this quite a few times, it's easy and there are a few really important things that can save you hours of frustration.
@NeedItMakeIt looking forward to see the process. I dont use fusion as my CAD program, but most of the techniques are the same in most programs 😀
I think it is important to focus on cooling the part, as this is in-fact the part cooling fan! Pointing the duct more towards the printed object just makes sense.
the relief ports on the stock duct may be for relieving static pressure on the fan so it achives higher RPM and air velocity.
As you keep adding ducts it has me wondering at what point is a torus style duct better? The type that would surround the hotend 360* and exit through a slot that faces the nozzle. You may end up going off the deep end learning fluid dynamics to solve this problem!
a design that you see a lot as well is the circular fan duct. i would love to see all of these ducts improved with those points you mentioned and see a second video on this topic. because i was trying to find a good fan duct for my printer as well!
Circular is a good option, I'd have to see what happens with that idea. I've mainly been using longer thinner rectangular openings. I have at least 2 more videos coming on this subject and I'll include some smoke testing of some kind as well to really get an idea of what's happening with them. I'd like to end up with a result that we can apply to any 3D printer and have better results than anything else out there.
@@NeedItMakeIt I was just about to refer you to a great video a creator did on air amplifier ducting then realised it was one of yours. Taking the suggestions from @HerrickAaron in an earlier reply it would seem maximising velocity of airflow is key. I now presume that video was deliberately related to improving hot end fan ducting. I do wonder how it could be directed at the extrudate rather than down and around the whole nozzle.
Stock K3 cooling offsets the two fans and that works quite well. However that’s two fans with very little ducting, the fans are pointing pretty much straight at the nozzle with some small nozzles attached to the output
Thanx for sharing your experiments !
Great video! One note. Your air should be cooling the part right below the nozzle, not the nozzle itself. The goal is to cool the filament as it is being extruded onto the layer. Cooling the nozzle isnt recommended as you generally want the nozzle to be as hot as it can be. You want the filament to extrude at the right adhesion temp, then cooled immediately to help prevent overheating / warping of that area on the part.
100% I agree with that. I've seen that the stock duct cools the nozzle far too much, and the single and double options I've created do as well, the others which are set off to a slight angle seem to do better, but I'd need to find a way to test this to see how much heater struggles to keep up. I really need an IR camera! I could design a version which places the air very precisely to test your idea.
Would've loved to see this done on more common printers like the A1 series. Also, will be nice to see the water test with the airflow for each duct on future videos. Great job as always.
I'd like to test them out and come up with the ideal option and then we can take that concept and adapt it to every single popular printer.
Very timely video for me, and I hope it creates lots of discussion about the best duct design 😊 I am currently designing a toolhead for the Creality K1 family of printers that use standard revo hot-end parts (revo voron) support several of the extruder models out there, and most related to this, a rear mounted part cooling fan so need to find a good duct design for that :) as always great video and information..
I’ve played with this a lot on my machines as well. Angle of attack is something I would consider as well for next video
please teach how to draw curved lines like that in 3D! also please share the bridge and overhang models!
I started working on the video last night to show how this is done, and of course we're going to have to take it to the next level as well and test that version out too. It should be a good one!
In terms of "path" the bend should be contiously differentiable twice so there is no "sharp" corner both in terms of direction and velocity(change) and short as possible so there is no loss
If we can get away with the double duct and have them offset to the side of the nozzle I think it's possible. I'd imagine that the long corrugated hose leading to the duct will cause quite a lot of loss also, I wonder whether a more flexible and smoother silicone hose would be better. Maybe for the next tests I need to use 2 printers, one with the CPAP and one with a standard blower style part fan.
Will be interesting to see the difference as ratio between inlet and the outlets will play a role too. Advantage of the CPAP is probably that it will be more "laminar" than a 5015 closely mounted to the ducting system(more equal pressure/flow across the inlet"). I am looking forward to the results. The fan showdown series by major hardware is fun to follow and hope we get some fun out of this as well
Great video. Looking for a guide on duct design for part cooling.
I've always assumed you want the air flow to not hit the nozzle, but to hit the plastic directly beneath where the nozzle is. and so I would assume you want an air flow angle that is the same as the angle on the bottom of your nozzle and you want them as consistent as possible all the way around. So whichever direction the head is moving, it will be blowing cold air onto the part right behind.(I have a Cheap delta printer that has really bad cooling performance, so I put a really big fan on it and it was blowing on the nozzle too much and cooling it off So I was getting nozzle jams)
I'm so confused, what about heated chambers? Do we want parts warm or cool as soon as the nozzle leaves filament?
For materials such as ABS and similar. You must turn off parts cooling or about 20% fan. Keep the part hot most of the time.
You want the part to be just cool enough to support the layer above. The hotter the part, the stronger layer adhesion. Heated chamber prevents overcooling. You can also passively cool, by printing many objects on the build plate. This allows the parts to gradually cool down without the need for a cooling fan. It is a balancing act especially if you bring cold air from outside the heated chamber.
That's a tough one, when printing with ABS, I print much slower and with almost no part cooling on, with PLA, we're talking more extreme speeds and much more cooling. I think it's a good topic to explore more, when "cooling" in a heated chamber, the air is going to be fairly warm so it cannot extract as much heat, in the case of these materials, it may be a good thing to make sure that the ABS or PC parts don't warp and shrink too much during the print.
super interesting! would love to see more videos exploring the other questions you raised neer the end!
I have at least 2 more planned already, I wanted to show how to make one yourself and then print and test that version and then I also want to explore the double version with offset ports and then we can go from there.
@@NeedItMakeIt awesome, looking forward to them!
Always had trouble printing dimensionally accurate small gears for the differential in 3d printed truggy by open RC. I put it down to inadequate cooling as some teeth in the circle curled up. Would be interesting to see how your designs handle that. Also just watched a video by Nathan Builds Robots about glass and carbon fibers in filament. You might not want to handle your glass fiber ABS with your hands anymore and make sure you have an air fillter running when printing with it. Can't wait to see the next video!
I'll find the gear and see if I can print it! Which filament do you use? For sure, that's a good topic he's on, I agree that we don't speak much about the long term health impacts of 3D printing. Coming from a Woodworking background, it's similar, except some of the particles are known carcinogens, specifically from hardwood lumber dust. It would probably be best to have a Room filtration system active at all times especially if you're working near your printer.
@@NeedItMakeIt For the small gears I was using ABS+. In the end I went with metal gears in the differential as it was cheap and I had other things I had to fix. If I were to try it again I would use Poly Carbonate as it is super strong, temperature resistant and cheap for its properties. A lot of engineering filaments get pricey quickly. I do really like my carbon fiber PC filament because it is way easier to print with. The fiber breaks up the polymer chains causing less shrinkage. The only downside is that the layer adhesion isn’t as good as straight PC. Don’t get me wrong, those parts are still really strong. I use the Carbon Fiber PC for my hotend fan ducts because it is light and doesn’t deform on my Prusa mk3s. Which I had ABS+ deform on me enough to start knocking prints. I voted for the three ducts with the vortex, it was only a guess though. Nice to see it work.
You mentioned doing a new duct for the Qidi Q1 Pro. Was wondering if you have any designs for that and/or are planning a video for that printer like you've done for this flsun one?
Would be very interested in improving the cooling on the Qidi Q1 Pro!
I'd love to do an option for every popular printer, including the Q1 Pro. Before that I was hoping to get some ideas from the community to test out and then we can come up with the best possible option together.
Hey dude,
Based on this video and your experience of the panda jet, I think a 3 or 4 duct design once you have the knowledge on offset positioning, duct sizes etc.
On the Q1 (And other Qidi printers), the probe is on the right and mounts for beacon or Carto place it behind the nozzle.
Placement of a 4 duct design maybe best at 45 degrees, 135 degrees, 225 degrees and 315 degrees.
For a 3 duct design at 45 degrees, 165 degrees and 285 degrees.
Those as the positions least likely to interfere with either probes but I guess that would be in the design work.
I also wonder whether the stock fan on the Qidi (with it's non-standard design) would be better or if it would be better to consider a fan swap with new duct design for Qidi printers?
Ive seen visible print quality improvement in all my printers when installing community designed shrouds. Especially on printers where I can go from one cooling duct to three. It makes a huge difference. In the same vein, these enclosed corexy printers like the K1 make no sense with the single giant aux fan on only one side of the print bed.
Does the side fans have any effect on the cooling, like a K1 with an extra side fan?
Great content! Get sponsored by one of the meal services that ships with dry ice, so you can use it to visualize where the air is going in each design. A little dry ice + boiling water makes a nice print bed full of mist.
I was thinking smoke pencil, but your idea is wayyy cooler!
Great video! This kind of testing is so interesting to me. It makes me wonder why the OEM can't do this and have 3d printable improved duct files available for people who want them. Saves them the injection molding costs, but provides a much better result to the customer.
Thanks! I think it's an area that needs a bit more attention for sure. I think at a minimum they could provide a file that could be printed at home. I think you're right, it comes down to cost and to some extent the look. I really like the open and somewhat organic look, but some people probably prefer the clean condensed version.
One caveat that I noticed early on (2019?) with different ducts is that the best bridging often happened when the fan cooled the nozzle... In other words, lowering filament temperature. It made it hard to find the actual best ducts because the "best" weren't the best
Happy Saturday! Great video to wake up to. Although it reinforced that I have to learn Fusion, sooner than later.
Me too😒...everyone uses it and I'm using sketchUp 2017 🙄😆. I guess I have to accept the adventures of the future😂
A lot of fans have the most pressure buildup at a slight throughtput. These side nozzles may be to archive slightly higher airflow.
Hello, I own my 3D printing compagny since 8 years : Zoltan3D.
I already tried how much cooling is great ... your tests in quality are nice ... but you forgot the most important part in this test !!!!
Yes, it's greater in overhang, but the prints become weaker with too much cooling because you don't let time to the filament to stick on the previous layer !
So yes, it can look cool, it's okay for a decorative object ... but it's WAYYY weaker with technical parts with too much cooling
These things look alien
👽
Very exciting and interesting topic. Especially because I wrote my exam in fluid mechanics yesterday. :D
Nice! Hopefully the exam went well. Do you have any insights into where you think we should go next with the design?
@@NeedItMakeIt Without CFD simulation this is unfortunately not very easy and even with it you often have to test new prototypes. The round profile is definitely the best to avoid pressure drop as it has the least edge friction. It also has the least turbulence, although the question is whether turbulence is good or bad in this application. Using the same inlet and outlet area for the three nozzles is important in any case, this is based on the flow law. To avoid pressure differences on the sections, the ratio of the length L to the flow area A should be as constant as possible (L/A). You could also use larger nozzles which would reduce the outlet velocity.
Slower velocities are also more laminar and can be improved with a grid of fine tubes.
I'm really looking forward to seeing what else you come up with. There are so many possibilities :D
Has Qidi Tech improved Q1 Pro firmware lately? Is it stable printer these days?
can you get the part number off the c-pap blower so we can find a data sheet and the size of the tubing it's using i want to do some detailed CFD on mine and optimize for an apx flow
I wonder if overhangs and bridges close to the bed get impacts from "ground effect". As opposed to similar features a few inches up, which wouldn't see any reflected airflow.
For my own DIY built 3d printer, I have the nozzle surrounded by a circle shaped duct.
It actively touches the silicone boot of the nozzle.
I have no idea how it compares to a more typical design, but I get pretty epic bridges out of it.
I've seen a few of these and I think they can work really well, it'll have to be tested against some of the other designs. the 360 surrounding version would need to be balanced out a bit better with larger and smaller ports, but it's doable for sure!
10:33 I would venture a guess that these small ports are to prevent excess static pressure. Also curious, depending on design, if these ports might actually suck IN air at lower flow rates.
I like the ideas for further testing, small tweaks lile duct shape. I would say though it always best to figure out a objective way to measure the results.
More are coming and we'll dial the testing in better as well! I'd also like to add smoke testing of some kind, in order to make educated decisions, we need to understand what's happening during a real print. A simulation is possible, but it's not going to provide much info about what's happening during the testing. I also wonder whether an IR camera would provide the info we need.
I would like to see you do a video that covers venting a printer to a window etc.. it is confusing for many with the pressure changes.. inline fans.. enclosures over enclosures.. directly from the printer exhaust.. from the top of the printer..I would love to print in materials like ASA but I want to vent the fumes..
you could make an "infinity duct" wrapping all around the nozzle in a torus, perhaps with the exit slot angled downards.
thinking about it more this would basically be an "aerospike" cooler
I think the "relief ports" on that one duct are to cool the part aswell. When printing really fast, the nozzl will not spend enough time near the recently laid down filament. That's why you have auxillary bed cooling fans on the bambu x1 and voron 0.2.
This would be similar to having an auxillary bed-widevcooling fan.
It could be, i guess I'd need to cover them up to see if there is any noticeable impact. I'm not certain that a CPAP can really replace one or two auxiliary fans, but I'd like to at least try. Having a part fan that can cool locally and also cool the rest of the part is a tall order.
Great content again!👍Very interesting topic too. Im guessing that downward facing ducts along the nozzle would warm and cool larger surface area of the print below.
If pointed along the printing plane same would apply more along the top layers of the print.
Which one is better might depends on the geometry are you printing.
Thank you! I think so too, there seems to be a lot left to explore on this and with some really fast printers coming out I think we're going to need exceptional cooling. The AUX fan is a good option, but I've found that if it only comes from one side, the results are only good on one side. I think it'd be good to dive in a bit deeper and really find out what makes for a good print and then we can design a duct for any printer using that same solution. I have a video coming soon where we look at the angle, whether horizontal is better or more vertical, also the position of the air related to the center of the nozzle laterally. You make a good point about the print itself affecting the results too. Some prints with infill will cool differently, and some infills also allow air to circulate better, which could also have an impact. Interesting stuff!
@@NeedItMakeIt i personally print alot of pla but also higher temperature materials in which you need very little or no cooling in order to have good layer adhesion and no warping. In these cases heat should be distributed more evenly and prevent early cooling.
Maybe for a good overall solution the cooling should be relatively even in directions along the printing plane. And how about suckin air away from the part?
I would also absolutely love to see a better duct design for the Qidi Q1 Pro! Do you have plans to make one in the future?
YES! I will make a better duct for every single common printer if I can. Maybe I should release a poll and then we can decide which to do first. The QIDI is still one of my favorite printers, especially for high-temp materials so it's going to be a good one to upgrade a bit more. What I'd like to do is take a bit more time to experiment so that we have the absolute best option. I'm also sending out a challenge to anyone who can do better and we'll have a face-off, my best vs anyone else's and the winner will receive a prize as well. I'll release a video on that subject so we can get some contest rules, but it should be fun and the result will be something even better I'm sure. Nothing like a bit of competition to drive innovation.
I've always wondered how the hell people design these things. Seems like a lot of really hard work, because they're so curvy and complex in their shape. Never had any clue how to do that in any CAD program.
What are the stakes/specs for the best design? I've got a pretty solid concept that I haven't seen approached by anything to date.
You found a fun little rabbit hole there. ;-)
As you were concerned, having a nozzle sock is a must especially with high flow. You should try again with good sock.
I think I'll have to create a mold and make one from some HT silicone! I agree, I also think the nozzle should be replaced with the CHT setup to get a little extra flow. There is a little problem with doing it because there is also a triple ported design inside the heater block, if those three don't line up with the three in the CHT, it could be a problem. Only one way to find out!
@@NeedItMakeIt won't socks from Amazon work? Or is your heater block too different for them?
I'm gonna have to look into a new duct for my ender 5 s1. The stock duct is okay, but certainly could use improvement
I think there's too much looking at symmetrical design, besides the vortex. However, the vortex does try to create a circle of air. I think you should try the tri-duct vortex but with only two ducts, that way some fresh air gets pulled in from the gap where the third duct was so you don't create a insulating air layer. Purely an opinion with no experience using FDM printers.
This is a good idea, I have the 2 offset duct test coming in the video I'll be releasing this weekend! I will also be adding some smoke and water testing for future testing videos to really understand what's happening with the air during a print.
Would love for you to make a video outlining the design process for these ducts in Fusion 360. Please consider such a video.
Hope to see the ducts upgrades you did on the Q1 Pro soon!
I'd like to have something for the Q1, the K1, the X1/P1, A1, and really anything else out there that could use an upgrade. I want to take a bit more time to really dial this in and get a good understanding of what produces the best results and then we can create a solution for every printer out there that needs one.
@@NeedItMakeIt WOW! Sounds great!
How do the results change if you angle the ducts to point directly at the nozzle?
I can certainly add this as part of the follow up testing to see!
Looking at the fan in the q1 pro you can get higher output fans. But im seeing the outlet is smaller in size then the stock. We would need a smaller inlet to the parts cooler. I suck at 3d software though lol
I thing you could try to print the next prototypes on resin printers vs fdm and see the impact of them. You k ow where I am going with this.
There are also the fans connected to the build plate rather than the nozzle. Moving a lot of air with big fans. But from far away
Absolutely, the AUX fans are another good option as long as they are on both sides, I've found that printers with only one have poor results on one side and good on the other.
Sometimes relief holes in a duct actually increase the speed of air inside the duct. It's why many air chucks have a hole in the side. If you remove that hole or cover it up, you can immediately see a noticeable drop in air speed. I'm not sure about those ducts specifically, but that's just a guess from other kinds of ducts I've seen in the past. (Edit, air passing across the inner surface of the holes can cause a vacuum, pulling air into the holes and greatly increasing the output/efficiency of the duct).
Very interesting, thanks for that information, it's certainly something to try, creating a venturi effect of sorts? I'd need some way of measuring wind speed at a very small scale to test this myself.
What type of air chuck are you referring to? Tire filling chuck? Air chuck on a lathe? or something else? Because in my mind I immediately thought of the blower attachment that goes on compressor hoses, for clearing away debris or drying off your workpiece. In this case, the hole in the nozzle is there for safety reasons. It is there to provide an alternate route for the pressurized air to escape in the event the nozzle comes in contact with someone's skin. Thus preventing a horrible kind of injury that makes my skin crawl just thinking about it. These are also not technically air chucks, which is why I think you may be referring to something else entirely.
So while having the ducts close to the nozzle seems logical, it depends on the print. Here you are print small objects where the amont of time for the air to do its job is aided by the fact that the nozzle will be back over the area soon. However take a longer print like a dragon or a house that takes up nearly all the bed and the motions are longer. Getting the nozzles too close limits how much time is available for them to cool the filament as the nozzle moves away. The only work around then requires an external source of air which may be obstructed by other parts of the print. Really I think where you had the ducts was good so they aren't impacted by the heater block which could deform things over time depending on the filament used.
Would love to see a Q1 Pro design!
I ve designed a 4020 (server fan with 35m³/h) fan duct for my prusa i3 bear and its so powerful that it's cooling the (imho too weak) bed so much till Klippers says the heating failed.
However ive chosen 3 ducts and its working great
I would love to see the 3 nozzle one designed for the older ender 3 and ender 5 hotends. or taking the existing Satsana and alter the air path to be off centered.
i would like to see the more downward. feell like it will cool the filament faster and the nozzle less. but I honestly don't know for sure.
What about a 360 duct that goes all around the nozzle and that tapers the edges a bit to create the vortex from the get go?
Yes! I love that idea.