Forged Carbon Revisited: Mould Design & Strength Optimisation
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- Опубліковано 4 тра 2024
- Order the kit ► www.easycomposites.co.uk/forg...
CAD files ► www.easycomposites.co.uk/lear...
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In this composites video tutorial we revisit the topic of forged carbon fibre to take a more detailed look at CAD techniques and best-practices when designing your 3D printed compression moulds, and also provide more detail on increasing component strength with the addition of long-strand unidirectional carbon fibre into the chopped tow reinforcement.
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Original Forged Carbon Video: • Make Forged Carbon Fib...
How Strong is Forged Carbon Fibre: • How Strong is Forged C...
Forged Carbon Fibre Development Kit
UK/USA/World ►www.easycomposites.co.uk/forg...
EU Customers ►www.easycomposites.eu/forged-...
Full Project Details (including downloadable CAD files for the compression moulds)
UK/USA/World ► www.easycomposites.co.uk/lear...
EU ► www.easycomposites.eu/learnin...
00:00 - Introduction
02:33 - Drone Arm Mould Design
06:57 - Linkage Mould Design
08:23 - 3D Printing the Moulds
09:28 - Mould Preparation
12:00 - Fibre Optimisation & Preparation
15:15 - Loading the Fibre & Resin
16:36 - Mould Compression
17:15 - Demoulding
17:54 - Finishing the Parts
18:45 - Strength Testing
20:10 - Conclusion - Наука та технологія
I thought I was done with forged carbon fiber, but this video is excellent, and has inspired me to give it another go. Right after I finish this ham sandwich.
Let us know the results.
HAHAHAHAHAHA...came to comments to suggest sfm might need to play with this again...did not disappoint.
Lose the bread and ham, the mechanical properties are a bit shit 😂
I still can smell that episode 😂
damn it I came here to make a ham sandwich reference 10 hours too late.
Absolutely loved the camera trickery when you showed the 3d printer running while talking. Fastest 3d printer in the world!
I was thinking the same thing. Someone has been polishing their video editing skills.
@@tomhollins5303 It's really easy though, you just talk reaaaally slowly and speed up the video
YESSS I came for this! :D I started 3D printing thanks to them and I loved to see that. It took me a while to understand he was bamboozling us, one year ago i wouldn't have noticed anything!
@@sovietmaize8277 Today's Job: Speak for 8 hours
almost sold me an ultimaker there for a second.
This is, by far, the best company advertising I've ever seen on UA-cam. Someday I hope to have our house and shop done so I can get this a try (I've done a lot of fiberglass work in the past). But, until then I still watch all your videos. These are awesome content.
Thank you very much. We wish you all the best getting your house and shop sorted and we'll be happy to supply you and hear about your projects when you get going.
Best composites content on youtube!
Thanks Robin, appreciate your support.
I see an easy composite video : I like the video first then I enjoy.
I saw it when i opened YT and a smile came on my face haha
Hahaha me too!
you have the smile of someone who earned their success
Haha, thanks. You've only got to watch through our 14 years of UA-cam videos to see that this is something we've been working hard at for a while. But enjoying it as much as ever.
The stop motion knolling with sound effects at 9:24 is incredibly satisfying.
Thanks. I think that was some expertly produced custom sound-scaping (our videographer Ben drumming his fingers on the table!).
This will most likely blow up just like your last forged carbon video! Great job, thank you!
Thanks. I hope it does 😃. This has actually become a process that we use quite a bit internally at Easy Composites as a great method of producing all manner of small moulded parts. The more it gets seen, the more people can add this process to their 'toolbox'!
@@IkarimTheCreature Oops, thanks for letting me know - I've updated it; replying to responses too quickly :)
@@easycompositestv Thank you for continuously bringing innovation to everyday people!
@@IkarimTheCreature It really is our pleasure.
@@easycompositestv Exactly! Just like carbon fiber skinning, forged carbon is something that is very much achievable by diy'ers at home, which makes it all the more interesting. Your videos are the reason why i now consider self made carbon fiber parts for my project cars, so thanks again :)
Still blown away these videos are free! Thank you guys so much I made brake levers for my goldwing after the first video and now after this I feel like my excf might need some 🤔
Thanks for the comment! i'm still riding on the levers made in that last video, I would have normally broken 2 or 3 in that time, maybe just good luck but they have taken a good few drops!
one of the best technical instructional channels out there. Informative and well presented. Order coming your way soon. That’s how it’s done folks.
Thanks for the kind words, it's appreciated.
Who knew these parts could look so good simply by not putting a ham sandwich in them
haha yes SuperfastMatt has some unorthodox methods!
The bread does tend to absorb too much resin
The sandwich is structural.
Me and a buddy used the Easy Composites kit and instructions to make a clutch lever for a husqvarna 701 SM and it worked absolutely perfectly! it was so exciting seeing the part come out of the mold looking almost perfect !
I just took delivery of your cast kit the other day, shipped halfway across the world, inspired by the previous video on the motorcycle engine cover. Can't wait to get started with this.
That's great to hear, I really hope you get good results with it. And of course, you know where we are if you have any questions or problems 👍
A new Easy Composites video?! LETS GOOOO
You guys.. these videos are so well thought out, jam packed with all the needed information and of the highest quality with the greatest attention to details. Already a customer, and I shall keep recommending easy composites. Keep up the fantastic work
Thanks for your support and feedback 🙂
I have had quite the success in following the last forged cf video, having made myself a set of thru axle rear dropouts for a bike frame. Thank you for encouragement, knowledge and inspiration to take on a new hobby, would never happen if not for this channel.
You guys know how to sell your products. You make such excellent, detailed videos that one can only appreciate the effort. I'm on the other side of the planet on a tiny rock but I am yet to find any company that comes remotely close to what you guys are doing and so you're getting some of my money as soon as I am ready to learn and do some composite work on my project car. Cheers.
Thanks for your kind words, they certainly make it work the time and effort that goes into them. Whilst you guys keep watching and enjoying them, we'll do our best to keep them coming. Feel free to get in touch when the time comes and you're ready to get stuck in.
That was one fast printer!
Still waiting for that video on moldless construction with infusion over sacrificial 3D print.
Also do a video on fasteners suitable for composite work and embedding metal parts into composites.
Another problem I saw with anyone making videos on composites - almost nobody makes structural parts, its all hoods, covers, shells and the like, glad to see something different here.
I know! It'd be great if they really were that fast though, right? Thanks for the votes/suggestions, they're all topics we do plan to cover.
@@easycompositestv the bambulab printers are almost that fast, you guys really need to upgrade from that ancient ultimaker
@@DingDongDrift They're not that fast LMFAO
@@gunsmoke132 i know it's not as fast as this clip, but still 4x faster than an ultimaker
Nobody makes structural parts because it's almost impossible to do on your garage😂😂 in Lamborghini we made the revuelto monocoque tub in forged, and it takes almost 8 years to develope, imagine in a normal garage without the right equipment😅.
I’m usually dumbfounded by some YT channels with high number subscribers, turning out poor quality, practically Usless and non educational content .
This channel has got to be in the top 10 and dare I say it TOP channel for technical quality, video production, professionalism and manners to name a few .
It puts the mainstream media including the BBC and many others to shame. You do genuinely deserve the views
👍🇬🇧.
Thanks for the kind words, it's appreciated. We try to improve with every video, not sure that we would quite rival a BBC production yet though!
So happy to see this video, I've been planning to try this method for FPV arms for a while, so seeing your approach is super helpful. This channel is an absolute gem!
Glad you found it useful, thanks for watching !
I love the small editing flourishes put in!
Every video gets better than the one before. Thanks for these insights.
Kit worked great, was a bit disappointed it came chucked in a plain box with no instructions, but knew from the YT Video and my own manufacturing experience what to do. great kit Just wish the presentation was better!
Thanks for revisiting this super cool stuff
Thanks for the feedback and I'm glad the process worked for you. We originally intended the video tutorial to be the instructions (in our experience, this is the way most people prefer to learn) and as such this is always the focus of our attention but it's good feedback to know that you expected, and would have liked, printed instructions too. As it happens, we have started putting together a PDF instruction booklet which will be downloadable from the product page (not that you'll need that now!) but I'll discuss with the team whether adding a printed copy to the box is something we'll choose to do as well.
Thanks for the reply! Even just a qr code to the youtube video would be great! Not even a full pdf, just a welcome flyer with a qr code!
Kit worked great though very happy! Top work guys keep it up thanks
The quality of your content is exceptional 👍. Highly appreciated.
Thanks for watching and commenting, it's appreciated!
The one and only paul, best notification on youtube what a guy!
Paul from Easy Composites, the hero we need!
This is a great vid!
I'm definitely using this method when building suspension parts for my streamliner later this year. 😀
I use this method to make components for my recumbent trikes. Cranks, suspension arms, etc. I'm glad more people are learning of these techniques from you! Most can't CNC aluminum at home, but with your methods they can get similar stiffness very easily.
Thanks for the comment, yeah it really is an engineering hack to get high performance parts without a big budget! Glad you've been making good use of it.
Thank you so much for making this video Paul!!!
Your videos are fantastic. Basically one of the best tutorials and education on UA-cam.
Thanks for the feedback, it's nice to hear they're worth the effort.
Curses! Just days after my order you add the long strand to the kit 😆 Great you're listening to feedback and yet again a great video.
Have you checked whether your kit has the long strand fibre in? - We did start adding it to the kits a bit early in preparation so it's worth checking. If you find you haven't and you have any future orders coming up, let us know and we'll include a pack of the long strand tow free of charge 😃.
@@easycompositestv I hope so as I paid extra :D
Great video. Really enjoy your tutorials on composite manufacture.
That's great, thanks for your feedback 🙂
Super video...great production as always
great video and great explanation as usual. I will need to design a part to use this process!
It's incredibly satisfying to read the comments on your vids. Everyone seems to genuinely positive. Also great advertising for your products. Whenever i see carbon fiber i think of you guys now.
Thanks for the support. We do like to think we have built up a great community of enthusiasts over the years so it is nice to see.
Damn good job as allways. You make crazy fine parts. Love it.
Just when I thought your videos couldn’t get any better, you drop this one!
Thank you so much for sharing your amazing knowledge with the world.
I’m so looking forward to creating my own forged parts.
I think I’ll start with my old school Kent 1600 Xflow Cosworth rocker cover for my mk1 escort.
Then I’ll try an inlet manifold for twin DCOE Weber carburettors.
Thanks again!!!
🇦🇺🤜🏼🤛🏼😎🍀☮️☮️☮️
Hi Steve, nice to hear from you as always. Off the top of my head, I'm picturing the rocker cover being relatively large, by 'forged carbon' standards. If you do give it a go, it might be worth starting with something smaller; the forged process is easier and more reliable on small, solid components, although the flywheel cover we made in the first video was probably a bit closer in terms of shape and size. Let us know how you get on.
That 3d print timelapse edit at 9:00 is real slick, man.
Superb video as always mate and awesome work on the parts.
Thanks for the comment Jon!
Superb video quality!!!
As always, thanks for the great video!
Thanks for your feedback 🙂
I like to think of 'forged carbon' as the oriented strand board (OSB) of composites. Some things you would never construct with it - but often it's strong enough for the job and really doesn't matter.
Your videos are very informative and appreciated! please continue making them
Thanks Dillbeet, we enjoy making them and intend to keep doing so - we have lots more either under way already or already planned.
Brilliant engineering skills! Thank you so much for sharing!
No problem, thanks for watching!
Moment Paul said Hi was the moment I had to give Like button right away
Your workshop is amazing!!!!!!!!!!!!!
Thanks! Yeah I love it in there, we've got some upgrades coming soon too!
Steven Spielberg of composites tutorials strikes again!
Great video and useful tips.
Thanks a lot
Thanks for the feedback, glad you found it useful.
thank you for another excellent video. especially for the extended cad on your website. you are like the titans of cnc of carbon composite but much cheaper to set up in your garage at home! 😄
You're very welcome. It's been something we've wanted to share for a while.
Excellent as always!
thanks so much, will definitely use those design tips soon
You're welcome, thanks for watching!
excellent video ! you have saved many hours and hours of frustration and learning curve has certainly been reduced in forging forwards ;)
Fantastic! Thank you for you amazing how to videos! 👌
Thanks for watching, Glad you like them!
Been watching your videos and they are great.
Thanks for watching.
love your videos and your enthousiasm, you look very passionate about your work and that make it entertainig and very interesting. thanks for sharing your knowledge. if one day 'll make the step from fiber glass to carbon it be hanks to you
Thanks a lot for the feedback and nice comments. If you do make the transition, and we've helped in some way, then that's great to hear.
The best of UA-cam. Seriously.
Thanks, glad you appreciate it!
Epic stuff as always there is no competition!
Thanks for taking the time to comment, glad you like it!
Liked, commented, shared, downloaded, thank you!!!
Well thank you too 👍
Nice edit of the 3d printing!!!
Yes, Thanks go to our videographer Ben for that!
Thank you!!
I haven't bought my 3D printer yet but you've just given me the ultimate use case.
love these videos
Love your content.
Gosh I love this channel
como siempre los mejores videos sobre la fibra de carbono
Top job🎉
Is there any virtue in offsetting the surfaces slightly more and building up a few layers of primer with an airbrush on order to improve the surface quality of the mould? Back when I worked in F1 we used TB650 and often that was pained post machining to improve the part quality. I can’t see how it wouldn’t help in this application….
I’m keen to get myself one of these kits and have a play. It’s brilliant that these kinds of technologies, coupled with the quality of consumer 3D printers these days, means that Joe Schmoe in his garage can knock out some decent quality carbon parts. The world truly is your lobster these days. Great vid as ever @easycomposites
Thanks for the comment, if you can find a coating that will bond to the print then absolutely you could improve the finish of the parts by finishing the moulds further, printing with a resin printer could also be a good option for improving the finish.
@@easycompositestv I have a resin printer so could give that a try, I wasn't sure that resin parts would be up to the job, but thanks for the pointer. Thinking about it, I could resin print patterns and then use something like TC80 to make the moulds from the patterns. Cheers
Super la vidéo 😊😊
Good to see this😊
You guys are so cool.... great video again. I love it.
Thanks, glad you've enjoyed it.
FPV love!!
Your back!
Absolutely awesome, as always such an amazing high quality production and packed with information!
One question for you, what about using Delrin for the mold?
Glad you found it useful. We've found that PetG provides a good combination of strength, releasability and print reliability but there may be other materials which work just as well that we haven't tested.
@@easycompositestv I have never tried printing with PetG but maybe I should try it myself.
I started 3D printing watching your videos, loved to see how fast can print that Ultimaker!! 🤣🤣🤣
professional video
This is a great video. Now I'm waiting for the full fordge engine with high temperature resins in the pistons and Conrods.
Thanks for watching. The issue isn't just the temperature resistance but also wear rates and variation in thermal expansion compared to more traditional metallic materials.
If you want to improve the strength of the drone arm even more with this method, you could have the long fibers added first and last, and using the chopped ones as a "core". Although it will be not as visually appealing as the chopped fibers. One solution for this is to add a very thin layer of chopped fibers, then half of the long ones, fill the mould with almost the rest of the chopped, and lastly the other half of the long fibers with some chopped ones over it for aesthetics.
The issue with this being that the long fibres are not able to 'flow' around the cavity and take the form of any surface detail which is present. The short strands on the other hand are far more manipulatable and can pick up this detail with far less risk of producing voids in the surface.
@@easycompositestv i have done this exact way about a month ago, by following your first video on forged carbon. after a few trials with molding, I came up with a 4 piece mold for drone arms almost like yours in this video. What a coincidence! After i saw this - got instant satisfaction that i was on a right track to make a successful mould. But i agree with previous comment - i ran long strands of tow as much as i could everywhere, and short strands around small features and on outside surface finish. it came out great!
i love these videos and i love your workshop 😎, very inspiring 👍🏻. usually i am having a problem and look for solutions in youtube. here it is the other way round 😂.
Haha! I think you're right, this is one of those 'that's a neat solution'.... 'what could it be the solution for?' situations.
Great vid, I keep saying one of these days I'll do a carbon fiber mold
Thanks for watching Paul. Maybe today is the day?!
A bonnet with a layer of short cut carbon fibers on the outside for optics and woven carbon fiber on the inside for strength would look simply out of this world.
Thanks for the comment, this is certainly something we could look at doing, it's perfectly possible.
Bought the forged carbon and prepreg kit to get to know how carbon fiber parts are made. Well I've made like 3 parts for my motorcycle out of the forged carbon fiber, now looking to replace the TC80 with resin printed molds as i'm already familiar with 3d modelling and I can be lazier lmao.
Thanks guys for bringing this knowledge with the kits to the general population :)
Thanks for watching, glad that you've been having success with the process, for sure printing the moulds is a faster route than casting with TC80, although the TC80 is more durable if you plan to make a batch.
@@easycompositestv Yea that was a concern of mine aswell. The tensile strength compared to the TC80(12-17MPa) is quite a bit weaker compared to the tensile strength of the e.g. Anycubic 2.0 Tough Resin wich is 58MPa). Sadly I couldnt find anything regarding the compressive strength but I will see how that translates into reallife use compared to the TC80.
Will be alot cheaper aswell as im still in school scrapping by on pocket money :)
@@easycompositestv If i plan to make more ill probably.... I dont know. Maybe CNC some aluminium or ill see the durability test vs the two materials
@@easycompositestv Yea okay, I had tensile strength and felxural strength / modulus mixed up. Yea the resin is quite a bit lower in the overall strength. Gonna see how that affects the moulds / if its even possible to create reiable moulds
Дякую!
Thanks !!!
Great to see the Fusion 360 integration into the processes
Glad you liked it, the extended version on our website has about 20mins on the CAD side if you're interested.
와 멋지다 나도해보고 싶네요😊😊
9:10 sick edit! 👍
Edit? That's just the latest firmware update ;)
Another GREAT video.
One detail though, for the drone arm: you've got the long tow fibers going down the middle of the part. You needed to do that because they don't flow like the chopped tow, and you used chopped tow near the surfaces of the part to get better conformation to the mold.
But this is a problem. That part is stressed in cantilever. The centerline of the part sees essentially no stress at all, which means your long tow fibers are right where they do the least good.
I'm not suggesting you've made a mistake. Rather, I think there's a fundamental tension here in designing forged carbon fiber parts, that all of us are going to have to deal with. I'd really like to see you address that tension in the high-quality way that you've made all these videos.
Various approaches I can imagine:
* In your suspension part, you've got the axis of compression across the width of the beam. This makes it practical for you to push the long tow fibers towards the areas of maximum stress. Good solution.
* You might load the drone arm first with long tow fibers, then chopped tow fibers, then finish with long tow fibers. I don't know how well this will conform to the mold.
I'd also like to see a discussion of where the air bubbles go. How do you avoid voids in the finished part? My guess is that you are dissolving the air into the epoxy by applying pressure. Is that true, and does it determine some minimum pressure that is needed to get a good void-free part?
Thanks for the well considered questions, you are right that loading the long tows more centrally compromises their potential but was done to aid flow into the contours, during the fibre migration they actually end up being forced to the outside more, also these arms face some of the greatest stress in frontal impact (not the direction tested) where they will be working more effectively. That said I could have done more testing and experimentation with the loading on this part.
With regard to the air entrapment, the pressure is primarily present during closure, once the tools bottom out the resin flows out until near equilibrium is approached, the air tends to escape very readily during closure as it is able to flow much more quickly to the low pressure regions (atmosphere) it very much depends on the part but a very low void content is typically achieved.
An excellent update to the process and understanding.
1 thing that could be addressed in the strength and stiffness tests and comparisons, is comparing a forged carbon components to an equivalent volume cast aluminium component.
Looking at the process and potential for things that could be produced this way, creating things that would otherwise be a cast aluminium part, could be really worthwhile.
My thinking is for producing custom car parts. Not necessarily for the looks, but for the real world application.
An inlet manifold is 1 thing.
But how about a bellhousing to create a unique gearbox and engine combination?
Where a creative person might come up with a bespoke mount for an older engine, to attach a power steering pump, a more modern alternator or an air conditioner compressor. Or something that incorporates 2 of those components.
For the comparison with solid aluminium, we've already made that exact video. After we did the original forged carbon video, we followed it up with a video dedicated to mechanical testing, I think that will answer most of your questions on that front: ua-cam.com/video/nhqAhYOdGNc/v-deo.html
As for some of the parts you've suggested, forged carbon right be appropriate for some of them but (without seeing the exact parts) I suspect at least some would probably be better made using a more conventional moulding process. This compression moulding 'forged' process works best for smaller, solid parts. If you're not familiar with them already, take a look through our back catalogue of videos where we cover a range of composite moulding techniques, including several that can be undertaken without too much by the way of complicated or expensive equipment.
3:44 That's quite a sound effect! I have a feeling whoever edited the video was not wearing headphones with good bass... Or was that a huge vehicle passing by the shop?
Maybe you've got better headphones! I'm checking it now and can't really hear anything, but we are on an industrial estate and operate a busy warehouse ourselves so a big truck is never out of the question!
The editor obviously (and rightfully so) knows that jungle is massive. 😁
When I saw the first video it was a real "ah ha" moment! I've made several parts using this technique and I absolutely love having it in my RC hobby toolkit! I might try making those arms just to build that quad!
Haha, that's great to hear. We bought the quad just to make the arms so you'd be in good company!
God I love this channel
Interesting to see those layer lines on the part! So you straight mould with the 3D parts after 2 passes of RW spray, and not sand and polish the prints before waxing. So 0.1mm lines height is enough to have so little lock to avoid prints postproduction.
It's a lot of time saved! Cool!
I think the reason they can get away with it is because most mould parts pull straight off close to perpendicular to the parts surface. If you were using a mould where parts pull off parallel to the surface and in an unfavourable direction for layer lines then the layer lines would likely cause issues.
You could sand the moulds for a smoother finish but for these parts the spray wax did a good job of reducing the majority of the peaks/troughs. It's also easier to finish the parts in the positive for the majority of the time, rather than try and sand all the little internal details in the mould. As long as you aren't makign a large number of pieces.
Amazing video again! Very useful info of how deep to make the cavity it is something i have been struggling whit until now.
An other problem i had particularly on small features is air entrapment and fibers not flowing in correctly. it is not a packing problem (usually appears on the piston side), it can be a compression problem but i do not have access to other than hand clamps, so i was thinking i could use vibration to help the process. In your experience could this help or just make things worse?
Good question and well explained. It's interesting that you've been experiencing air entrapment, and interesting that it's predominantly on the piston side. I can picture how, if it was going to occur, that's where it would happen. Is there any possibility that you're underloading the cavity? Although air pockets could occur (especially in some geometries) the clamping pressure is normally sufficient to overcome them. One possibility (not that we've needed to do this ourselves) might be to introduce a 'vent' hole into the mould design (or just drill one in now) to the area where the air entrapment is occurring. It would need to be very small in diameter to prevent reinforcement from escaping but *might* help. As for vibration, I honestly don't know if that would help or not, it's not something we've tried. If you do give it a go, let us know whether it helps.
@@easycompositestv Thank you for the the tip's. Will try them, and let you know if vibrating works.
Been wanting to do this for years since I saw your first video. But no shipping to Iceland. But anyways, great work on the comprehensive guides
Thanks for the comment, yeah Iceland is a tricky one for dangerous goods shipments (resins) we do ship palletised consignments there. If we ever find a way to get smaller orders there we will do.
Hi , love all your videos and hope to one day make some custom parts at home, do you guys have any opinions on triaxial carbon fiber?
Thank, you know where to find us when you're ready to get started. Triaxial cloths are great when you need strength in every direction with no bias.
I learned incredible amounts from your videos and continue to do so and use these techniques, thank you! BTW the 22.04 @ 12:56 is supposed to be 18,16g, that threw me off for a sec there!😅
Thanks - this has been corrected in the website version.
Another great video! When I tried doing some forged carbon after your last video, I struggled a bit with small air bubbles being trapped. Is there anything you can recommend to minimise that risk?
Bubbles are usually down to fibre loading and there not being enough material in the mix. Try increasing it slightly and see if that helps with the issue. Also make sure you coat the mould pieces with resin before adding in the chopped tow can help.
Hey guys I´m a big fan of your videos :) Sometimes unfortunately I get dry spots and other imperfections in my laminates. Obviously it would be better to prevent those in the first place. But in a formula student team with limited resources it would come in handy to know how to fix those imperfections without laminating a new part. Perhaps you can give me some useful tips or you might have enough ideas for a new upcoming video. Thank you in advance. Keep up the good work
Glad you find them useful. It's important to try and ensure that the fibres are fully wet out before you add more, be that more chopped tow or the next layer of fabric cloth this will help to reduce dry spots. Additionally drawing the resin up from underneath rather than applying it from the top can indicate that the resin has fully saturated through. If you do get dry spots on the surface you can remedy them with a coating of XCR, we actually demonstrate this technique in our '3D printed mould to carbon fibre part' video so would be well worth checking that out.
You should have the long tow at the surface of the part. The shear stress is largest at the central plane running the length of the part, where the fibre direction should be parallel to the force applied. I’m sure that unreinforced epoxy would be plenty strong for drone parts but basic stress characteristics are very useful for these projects
We should have covered this yes, in the case for this part having the chopped on the surface allows it to flow into all of the details, thanks for watching!
Great video. I expected some sort of oven curing but I guess it’s not needed or wouldn’t add any additional benefit?
Depends entirely on the epoxy used. Some cure at room temperature (but have lower shelf life) while others need high temperature to cure.
As Chuck said, it depends entirely on the resin. You could post cure these parts to improve mechanical and temperature resistance properties. Given that we used 3D printed moulds doing an 'in mould' post cure to support the parts would be limited to fairly low temperatures.
I was doing work like this in the early 1980's except my moulds were created by pouring mould making epoxy compound around a master pattern. A bit trickier but overall it worked quite well.
We do show that method in our original video but as you say it does require a physical pattern or part to copy. For each part of the mould tool you also need to wait for the previous one to cure. The joys of modern tech allow all mould pieces to be printed at once.