Yeah, this really makes a huge difference. It also helps to have the camera as close to square with the object as possible. Moving back makes that easier as well. For the best reference photos, I'll even break out the DSLR with a telephoto lens. Including a ruler in the photo (in the same plane as the object) makes setting the scale easy if there isn't already a good reference point. Another trick that works for flat parts is using a flatbed scanner. This gives you an orthographic view as well as a known scale (the scanner DPI).
A way to get perfectly flat camera to a given face is with a mirror. If you center the reflection of the lens into the center of frame then the whole optical path is perpendicular to the plane of the mirror.
@@shaocaholicathat's as close as you can get with a regular lens, and is perfect at the center. But what you really want is a hypercentric or telecentric lens.
This continues to be my favorite channel on UA-cam. The enthusiasm, attention to detail, excellent explanations, and craftsmanship always makes my Saturday evening. Thanks James!
Great times for makers, you’re right. Being in the same age group, I think that younger than us do not realize this enormous technological and logistical leap that we have experienced over the last 30 years. Those days when your simple datasheet of banana jack was sent by post, in 2 weeks 😂
Nice little adapter. For precise positioning in KiCAD board layout, I typically place a Drill Origin and Component Origin in the lower left of my outline (or equivalent for curvy boards). Then ensure Preferences > PCB Editor > Origins & Axes > Display Origin is set to "Grid origin" (it uses "Page origin" by default, iirc). This allows you to type in the absolute coordinates (using mm or inch) for items in your design in the Properties dialog [E], like you were showing. Some other helpful tools under Right Click > Positioning Tools: Move Exactly [Shift+M] allows specifying X/Y movement & rotation relative to the object origin. Position Relative To [Shift+P] will let you select a reference object as the new origin and position relative to it. I also noticed when ordering boards at JLC that quantities above 50 will put you into "Small Batch" mode, which changes how they calculate the cost.
4mm banana jacks are usually only rated to 15A (and 30V). Cheaper cables tend to be even lower. The DC load can handle 30A, easily enough to melt 4mm banana jacks. *That* is why it doesn't have the combos. Don't use these past 15A at most and it'll be fine.
I’ve always been impressed with your ability to design and create professional looking parts and despite the simplicity of todays project… I was blown away. It’s exactly as you said at the end … We really do live in such wondrous times, one where it’s possible for a single person to design and 3D print a rendered product to verify fitment and tolerance levels. Then upload their files to be manufactured halfway across the world then subsequently receive 50 finished products that very same week for $70 shipping included … You can’t help but get inspired from watching this kind of thing.
Nice neat project. The binding posts are probably used because 30 amps is beyond the rating of most 4mm banana plugs. Hirschmann plugs are rated at 30A, but are expensive and not widely used. Are you happy that the PCB clearances are good for the 150VDC the load is rated for? It looks a little tight.
It seems to me that I would have put more copper on the sides to increase my surface area but I would have cleared the center a little more or simply made a slit there where it is the tightest.
While Carbon filled plastic isn't 'conductive' (compared to say composite Carbon or long fibers) you are still likely to have some leakage current limited coupling issues.
@@Clough42 Easier is just doing the part in PLA. Interested to see if you can get anything meaningful from the CF filled Nylon regards a measurement in particular a repeatable one.
Thank you James, in these amazing times we also have amazing people like yourself who show, teach and inspire us to make the most of these capabilities and resources available to us as well.
Nice video and project. Another option is there are high current M6 binding posts with banana sockets in their center cap. I have the Rigol Electronic Load and I just unscrewed the caps and replaced them with the caps from the ones I got from Aliexpress USA. You get two complete binding posts sets both red and black for around $10.00 USD. Of course, the banana connections cannot handle the full current capability of these Electronic Loads. Again, thanks for the great video!
Even more amazingly, with two of your other personal robots, you could even do everything at home. You could use your CNC mill to route and drill a board, and you could use a resin printer to use UV to image the design onto UV sensitive mask.
Yeah, I walked away from home PCB manufacturing a long time ago. The etchant is complicated to handle and store safely in a residential environment with limited space, and the results are never going to be as good as a commercial fab--especially with multilayer boards and modern solder masks and silkscreen.
@@Clough42 To each his own - to me, $50 (plus shipping) would be a horrifying expense for a small board I really only need one of, and the small desktop CNC routes it out for me the same day for free instead, no chemicals involved. I wouldn't design an ARM SBC running Linux this way, but I sure do and did up to Arduino-level complexity, even with SOIC14 chips.
You can import dxf files as board outlines in KiCAD if you wanted to do that as an alternative. I've done it a few times, designing the board outline in AutoCAD first.
Same here, from Solvespace directly to Kicad board outline; and if you chose any kind of sane origin point, placing the outline exactly where you want is simplicity itself. If you included the holes you are interested in with the outline, you even get snap guides of where to put down your parts/traces...
It seems that the post spacing is somewhat universal. I bought two of these -- one for my Multicomp DC load, and one for my B&K Precision DC load. It fits the Multicomp perfectly, but the posts on the B&K are slightly larger diameter, but then I noticed that they're a bit larger because they also have the banana jacks in the center already, so I ended up only needing one.
Consider a third layout option: If it is symmetric, and double sided, then it might be possible to create a PCB which allows mirror image to lower left or upper right placement. The pick would then be based on which side you solder the banana plugs to. If you had banana plugs which connect via threads, then it might be possible to unscrew the jacks and put them on the opposite direction. The universe likes symmetry, so do I! 😀
I have that same electronic load. I simply bought some 6" long 12AWG speaker wire leads that adapt from a banana jack to a big fat spade terminal. I never considered doing something fancy like this, but it looks nice! I'm familiar with KiCad, and I have a decent 3d printer, so I have no excuses!
Until recently I made crude PCB's at home, using the laser toner method. Ordering small quantities at reasonable prices prices wasn't possible. No more; the last board I did I ordered 10 boards for $5 with a $5 New Customer coupon, so I only had to pay for shipping(!) And I got pro-quality 2 sided boards with solder mask and silkscreen. Amazing. The only mistake I made was using standard China Post shipping rather than paying a little bit more for DHL; won't do that again.
Wow, I've been patiently waiting for your electronic lead screw to be in shock and it looks like I got mine just in time, they're almost gone already. 👍🏻
Nice work as usual, James. As a pro solderer and electronics lab manager I have a few suggestions: For soldering "heavy" PCBs invest in an under board hot air preheater, like a Metcal PCT100. As others have mentioned a flux gel will also help a great deal, I'd recommend CIF F42202. This can be removed with Isopropyl alcohol or most "flux remover" sprays. If you dont already use fume extraction when soldering you'd better get some of that too! 😊
This one would be rough for a heater because of the jacks, but I definitely use flux. Wiping everything down with a flux pen first makes a tremendous difference--especially on the jacks.
@@Clough42 The preheater could be set so that it didn't get hot enough to damage the jacks, and/or the jacks could be protected with some tin foil. It's there to raise the temperature of the PCB so that it's not just instantly sinking the heat from your iron and probably wouldn't melt those jacks even if it was set to "10". It's no hotter than a reflow oven.
@@willej78the jacks probably aren't rated to survive reflow oven temperatures anyways though. And the jacks would be closer to the heating element than the PCB itself that's making it more difficult. I don't disagree that having a pre heater would help a bit but I recently did a very similar thing and it was quite difficult to prevent the components on the other side from melting and still achieve any sort of meaningful preheat.
An alternative option is using a hot air gun aimed at the same side your soldering on held in place by an indicator armed with a clamp or something similar
@@MarkFunderburk Yes indeed, hot air pencil in one hand, iron in the other! This is a technique we use a lot on the boards we rework where I work, most of the time with them on a preheater too.
Another great video . How about a shop tour some time to show how much space you need to have to set up equipment and allow for work flow. Maybe some advice what you started with and you most used and valuable piece of equipment.
Excellent execution on all fronts, stable functional, simple, but also properly engineered to last. I think the only thing I would consider changing, is select an ENIG PCB finish, so it's more tarnish resistant, and insulate the back of the banana jacks, since a finger could theoretically curl in behind and touch those in a moment of panic or something.
One thing I've played with these type of low-run boards is going with very thin PCBs and doing my own sandwiching. If I'm going to pay for 10 boards, but only need 1, I may as well sandwich 5 of them and get some beefy combined current carrying capacity. It doesn't necessarily multiply that well, and it comes with its own design challenges (if you think 2oz copper takes a lot of heat... imagine trying to get 10 combined layers in there), but it can be an interesting solution
That's a good idea. The stud on the back of these jacks barely penetrates one 2mm board, so maybe not for this project, but in general, that would be a great way to increase rigidity--especially if the boards are clamped at multiple points.
I sometimes find that a really good rework flux can make working with lead free solder much easier. I often use AMTECH RMA-223-TFU(UV), down side its a sticky messy flux. So a ultra sonic wash, or considerable time with isopropyl alcohol and a brush. I was introduced to it for BGA soldering and smd rework. Though I know they make versions that are easier to cleanup. But I haven't needed to replenish my stock.
I used a Kester #951 no-clean flux pen. It's great for wiping down stuff like these banana jack terminals, but it flashes off a little too quickly to be great for rework.
I liked the look of the low jacks better than on the side, but I can see one advantage of the side: the wires will hang over the test equipment you have below as is. They're more out of the way on the side...
ok - over complicated - i did same: wrapped wires around lugs and used washers and screws done in 5 minutes - however - fun to watch and complain about! keep em coming!
Measuring across the output terminals with the calipers ('shorting' the output) gave me the willies (even though of course you had the output safely turned off). Usually if I'm measuring terminals etc, I'll use my junky plastic calipers - they're usually sufficiently accurate but won't short out my batteries when i measure how long a buttontop 18650 battery is. You can guess how I learned that lesson...
There is a reason why it has these binding post.. Because you are supposed to use thick gauge wires for this and not banana jack measuring cables which are not designed for this purpose. This is why 90% of these DC Loads have these posts. Used to be a time that companies would not have to think about such things but in this era where people try drying their wet dogs in the microwave (yes I know this is an urban legend but it explains best what I mean) they have to make sure or get sued.
@@Clough42 It says right on the front of that unit between the banana jacks ... 10A max. If you want the 30A you have to use the MUCH bigger screw terminals in the back :) Same reason :)
Although your design is fairly rigid, I wonder if using the entirety (almost) of each side of the PCB as a single trace (e.g., bottom side negative, top positive) would increase the rigidity a bit more. I'm not sure if the capacitance would interfere with the operation, though.
I'd please like people like you to design all the products I have to use. If that makes the products more expensive, I'll just buy each one 50 times to save money. ;-)
I would have made the traces wider or even flooding the board. The copper is just etched away so it shouldn't impact cost. There is a free program called Saturn PCB Design for doing PCB calculations. Oh and the 15 amp calculation is very conservative. Good job.
Great video James! I've been slowly developing my F360 skills and got so much out of watching your design process. Thanks for doing what you do. I'm a fan.
That's a satisfying bit of design, elegantly implemented. I wonder why Siglent didn't just counterbore the binding posts with a 4mm hole down the centre. I know that this wouldn't have given the 19mm (3/4") spacing but would have probably been sufficient for most applications.
I've been wondering the same, but frankly looking around the market only BK Prescision seems to have accounted for that. Neither Rigol as a manufacturer on the same level (though they have the sense terminals on the front, which is nicer in a lab environment), nor Keysight, nor Tektronix as a premium manufacturers have that either. The reason is probably simply because most banana jacks are not rated in the same range as the electronic loads themselves, though there are quality ones that are rated for 1kV/32A, they are usually shrouded as well. But as a manufacturer that is always kinda dodgy depending on the market you supply, even if you put some stickers or labels on it. The 19 mm spacing is also kinda pointless anyway. I think that only really makes sense if you want to use BNC adapters like here, though I frankly have no idea why I would want to do that. BNCs are typically not great for power connections and given the load is rated up to 150 V it seems kinda dangerous conceptually for something that has one side always exposed (well I know there are shrouded BNC, but they are quite rare). The only other thing comming to mind with 19mm banana jack spacing are some thermo coupler adapters for DMMs. As for the siglent, I think the SDL10x0-y series is kinda due for an overhaul anyway, at least comparing it with other stuff that clearly has a more modern look and feel to it. Maybe they will at least think about the sense terminals in a future overhaul of the design. But I wouldn't mind if they flat out steal the BK Prescision Model 8510B knobs. ;) Edit: Ironically the BKP Model 8510B also claims 120A capability, which way out of league for any kind of bana jack on the market. So at least they don't seem to care. But I don't fancy spending 2k+ on a DC electronic load. That used to be something you just build yourself with some power transistors, coolers and a bench multimeter...
I swapped my binding post to accept banana plugs a while back. What I did was easier and works good. Search for 100 amp 6m binding post with banana plug, All you need to do is swap binging post nut. That's if your original binging post are 6M
Adapter looks nice. I did the same thing with the BJ's centered below the binding posts. Makes them a little higher off the bench than your design. I machined a couple banana jacks from brass rod. They are fastened to the board with M3 brass screws and solder (full high test 63/37 leaded Kester. ) Initially used a big traces then, realized two copper pour areas would have lower resistance with better heat dissipation. Also made a set for my bench power supply as well. Yo China engineers, banana jacks go on 19.05mm spacing!!!!
There's a good reason why binding posts are seen on mearly alp electronic loads. Its due to the limited current carrying capacity of banana jacks. You can get them that are rated for over 15 amps, but they aren't common, nor standard. And it would be easy to mix up cables in the lab.... and end up hooking up regular banana leads that aren't rated for that type of current
@@Clough42 I guess you mean the Siglent SPS5041X? Well at least the silk screen on the fronts says the front panel is only for 10A. I'm curious if they actually limit it for the front connectors or if you could fry them accidentally.
Beautiful work. I think I would have just spilt the PCB on a diagonal down the center on both sides (why use traces at all?) to minimize the IR loss, but this would only matter for high precision work. I love the CAD explanations. I always learn something.
2 things. Carbon in this form is not conductive at all? Wouldn't you have had the advantage of practically separating your PCB in 2 with copper in order to maximize the surface area for each pole? Really a great result!
Ha, I've been thinking about making something similar for my siglent SDL for a while. Heck, since I've seen the tektronix one with the awsome knobs that have the safety banana plugs integrated I've been trying to find them any maybe use these, but alas no luck so far. As an alternative I was thinking about something with a stackable 2 PCB solution (including some screw terminals to wire 2 cheecky wires along the bottom for 4 wire measurements to the back), but I always held off because I was kinda worried about insulation. Your solution is quite nice though and would seemingly fix my insulation concerns as well. Great projet idea.
Great video with a classy outcome! Um, I’m sure you iterated through this, but is there any potential for conduction through the carbon fiber rilled nylon? I couldn’t rightly see enough detail on my phone to catch any consideration included.
You could have gotten more power rating if you exposed the traces and let them get some of that sweet hasl action. It'll thicken em up and reduce their resistance for free.
Does it matter much how you connect to an electronic load? I have access to a number of Sullivan decade boxes from the 1950s and 60s and they don't have 4mm connections, just a plated brass stump and screw. I cut a 4mm test lead in half, then strip and screw the bare copper down super-finger-tight. That's good enough for two wire use. For four wire, I put the P terminals on the brass stump and get the residual resistance Sullivan put on the plate over half a century ago. I will add: these are 0.05% boxes, and meet that spec today.
Has anybody tested the electrical resistance of the BL PAHT-CF? I know plenty of other PA12-CFs have surprisingly low resistances, but I haven't seen it listed anywhere in their published data.
@@Clough42 Glad to hear it! I get worried when manufacturers don't bother to mention electrical characteristics on their datasheets 😀 Does your voltage drop change at all with the cover on versus off?
This really is one of the best engineering channels on youtube. Amazing work. I am curious what you think about the infosec issues with the bambu labs printers. Everybody says they are great, but I can't bring my self to rely on their fog to make it work. I'm about to pull the trigger on a Qidi Max-3.
I just noticed you have a i-fast review which has most of the same features. Would you still go for an i-fast at the lower $1700 price point, or would you go for the max-3? Seems like the heated chamber means they can do similar things, seems like you are trading speed/kipper for dual head/linear rails.
Carbonfiber for something ment to be an insulator? An odd choice. I know the 3d printed stuff isnt anywhere near as conductive but still not sure its the best filament for that application.
Hi James! I really learned a lot from this video. Thank you. Here's a follow up idea and a request. I was wondering if you might be interested in providing some basics tutorial, in your elegant way, about making/ordering/specifying simple PCBs like this, KiCad, and PCB providers. I am pretty fluent in Fusion 360 but have never used KiCad but do have some basic electronic and electrical knowledge. I have never ordered or configured any PCB's. It's likely that I'll need to use PCB's in a way similar to you have here, in that the parts will be more of a standalone object without complicated circuits. I would love to know more about KiCad, why/when it's beneficial as opposed to Fusion, and what files should be exported/used. You mentioned KiCad, Fusion, and the PCB provider's website would've required some additional work that you chose not to do. What are the considerations for this that someone like me should be aware of? Thank you for all that you do and show us!
Oh wow, I would have been furious designing the board from the dimensions of the 3D-model, and then find out they needed to be fit with a hammer. That's not cool from Pomona!
Did I miss an explanation of why you didn't just make longer nuts that you can plug a banana jack into? EDIT: I guess that wouldn't work for the 3/4" spacing double plugs.
Trying to understand where a centre-centre distance of 30mm comes from when you measured 30mm across the outside of terminals. If they're 6mm in diameter then wouldn't the C-C distance be 30-(2*1/2*6mm) = 24mm?
James, if the fixing pads had not connected the central pad would they be insulated and not require the shroud? Also if you flip a 2nd board will that give you 2 pairs of terminals?
I have never used Kicad but have used EAGLE, now called Fusion electronics. If you are using Fusion 360, why not use Fusion Electronics that is already included with F360? What are the advantages of using Kicad over Fusion Electronics when you can iterate back and forth between MCAD and ECAD seamlessly?
If you want a more "flat" reference image, move further back from the object you're photographing and zoom in on it.
A completely flat orthographic image is infinitely far away with a focal length of infinity.
Yeah, this really makes a huge difference. It also helps to have the camera as close to square with the object as possible. Moving back makes that easier as well. For the best reference photos, I'll even break out the DSLR with a telephoto lens. Including a ruler in the photo (in the same plane as the object) makes setting the scale easy if there isn't already a good reference point.
Another trick that works for flat parts is using a flatbed scanner. This gives you an orthographic view as well as a known scale (the scanner DPI).
A way to get perfectly flat camera to a given face is with a mirror. If you center the reflection of the lens into the center of frame then the whole optical path is perpendicular to the plane of the mirror.
@@shaocaholicathat's as close as you can get with a regular lens, and is perfect at the center.
But what you really want is a hypercentric or telecentric lens.
For small parts, use a flatbed scanner. It had very little parallax error.
This continues to be my favorite channel on UA-cam. The enthusiasm, attention to detail, excellent explanations, and craftsmanship always makes my Saturday evening. Thanks James!
"Today, we're going to over-do something simple..." Really good episode...
Great times for makers, you’re right. Being in the same age group, I think that younger than us do not realize this enormous technological and logistical leap that we have experienced over the last 30 years. Those days when your simple datasheet of banana jack was sent by post, in 2 weeks 😂
Nice little adapter. For precise positioning in KiCAD board layout, I typically place a Drill Origin and Component Origin in the lower left of my outline (or equivalent for curvy boards). Then ensure Preferences > PCB Editor > Origins & Axes > Display Origin is set to "Grid origin" (it uses "Page origin" by default, iirc). This allows you to type in the absolute coordinates (using mm or inch) for items in your design in the Properties dialog [E], like you were showing. Some other helpful tools under Right Click > Positioning Tools: Move Exactly [Shift+M] allows specifying X/Y movement & rotation relative to the object origin. Position Relative To [Shift+P] will let you select a reference object as the new origin and position relative to it.
I also noticed when ordering boards at JLC that quantities above 50 will put you into "Small Batch" mode, which changes how they calculate the cost.
4mm banana jacks are usually only rated to 15A (and 30V). Cheaper cables tend to be even lower. The DC load can handle 30A, easily enough to melt 4mm banana jacks. *That* is why it doesn't have the combos. Don't use these past 15A at most and it'll be fine.
Apparently a sign that says "max 15A with banana jacks" wasn't good enough, according to some guy EEVBlog once interviewed.
@@johnalexander2349😂 👌chefs kiss
I’ve always been impressed with your ability to design and create professional looking parts and despite the simplicity of todays project… I was blown away.
It’s exactly as you said at the end … We really do live in such wondrous times, one where it’s possible for a single person to design and 3D print a rendered product to verify fitment and tolerance levels. Then upload their files to be manufactured halfway across the world then subsequently receive 50 finished products that very same week for $70 shipping included … You can’t help but get inspired from watching this kind of thing.
Nice neat project. The binding posts are probably used because 30 amps is beyond the rating of most 4mm banana plugs. Hirschmann plugs are rated at 30A, but are expensive and not widely used.
Are you happy that the PCB clearances are good for the 150VDC the load is rated for?
It looks a little tight.
Nearly word for word the comment I was going to leave
It seems to me that I would have put more copper on the sides to increase my surface area but I would have cleared the center a little more or simply made a slit there where it is the tightest.
While Carbon filled plastic isn't 'conductive' (compared to say composite Carbon or long fibers) you are still likely to have some leakage current limited coupling issues.
It's easy to test.
@@Clough42 Easier is just doing the part in PLA. Interested to see if you can get anything meaningful from the CF filled Nylon regards a measurement in particular a repeatable one.
Thank you James, in these amazing times we also have amazing people like yourself who show, teach and inspire us to make the most of these capabilities and resources available to us as well.
Install with thin custom nuts. Then you can still use the knobs. LOOKS GOOD
For some applications you might consider pomona model 1614A they are rated 15A
Nice video and project. Another option is there are high current M6 binding posts with banana sockets in their center cap. I have the Rigol Electronic Load and I just unscrewed the caps and replaced them with the caps from the ones I got from Aliexpress USA. You get two complete binding posts sets both red and black for around $10.00 USD. Of course, the banana connections cannot handle the full current capability of these Electronic Loads. Again, thanks for the great video!
That's a nice little project....very nicely done!. That's a nice little project....very nicely done!.
Even more amazingly, with two of your other personal robots, you could even do everything at home. You could use your CNC mill to route and drill a board, and you could use a resin printer to use UV to image the design onto UV sensitive mask.
Yeah, I walked away from home PCB manufacturing a long time ago. The etchant is complicated to handle and store safely in a residential environment with limited space, and the results are never going to be as good as a commercial fab--especially with multilayer boards and modern solder masks and silkscreen.
@@Clough42 To each his own - to me, $50 (plus shipping) would be a horrifying expense for a small board I really only need one of, and the small desktop CNC routes it out for me the same day for free instead, no chemicals involved. I wouldn't design an ARM SBC running Linux this way, but I sure do and did up to Arduino-level complexity, even with SOIC14 chips.
That's a nice little project....very nicely done!
You can import dxf files as board outlines in KiCAD if you wanted to do that as an alternative. I've done it a few times, designing the board outline in AutoCAD first.
Can confirm.
I do the same with EasyEDA and Sketchup.
Same here, from Solvespace directly to Kicad board outline; and if you chose any kind of sane origin point, placing the outline exactly where you want is simplicity itself. If you included the holes you are interested in with the outline, you even get snap guides of where to put down your parts/traces...
Top notch work! Very clean solution to a "Is this a problem".
You are really handy with that 3D stuff. Thanks for the video keep on keeping on.
It seems that the post spacing is somewhat universal. I bought two of these -- one for my Multicomp DC load, and one for my B&K Precision DC load. It fits the Multicomp perfectly, but the posts on the B&K are slightly larger diameter, but then I noticed that they're a bit larger because they also have the banana jacks in the center already, so I ended up only needing one.
I love the whole process you went through to design and build this.
Consider a third layout option: If it is symmetric, and double sided, then it might be possible to create a PCB which allows mirror image to lower left or upper right placement. The pick would then be based on which side you solder the banana plugs to. If you had banana plugs which connect via threads, then it might be possible to unscrew the jacks and put them on the opposite direction. The universe likes symmetry, so do I! 😀
Love these projects
Nice work on this James, I like your style and thought process! I also very much hate you for getting more projects like this completed than me ;-)
I have that same electronic load. I simply bought some 6" long 12AWG speaker wire leads that adapt from a banana jack to a big fat spade terminal. I never considered doing something fancy like this, but it looks nice! I'm familiar with KiCad, and I have a decent 3d printer, so I have no excuses!
Until recently I made crude PCB's at home, using the laser toner method. Ordering small quantities at reasonable prices prices wasn't possible. No more; the last board I did I ordered 10 boards for $5 with a $5 New Customer coupon, so I only had to pay for shipping(!) And I got pro-quality 2 sided boards with solder mask and silkscreen. Amazing. The only mistake I made was using standard China Post shipping rather than paying a little bit more for DHL; won't do that again.
Very wonderous times. I don't want this part of society and international cooperation to end.
Wow, I've been patiently waiting for your electronic lead screw to be in shock and it looks like I got mine just in time, they're almost gone already. 👍🏻
Nice work as usual, James. As a pro solderer and electronics lab manager I have a few suggestions: For soldering "heavy" PCBs invest in an under board hot air preheater, like a Metcal PCT100. As others have mentioned a flux gel will also help a great deal, I'd recommend CIF F42202. This can be removed with Isopropyl alcohol or most "flux remover" sprays. If you dont already use fume extraction when soldering you'd better get some of that too! 😊
This one would be rough for a heater because of the jacks, but I definitely use flux. Wiping everything down with a flux pen first makes a tremendous difference--especially on the jacks.
@@Clough42 The preheater could be set so that it didn't get hot enough to damage the jacks, and/or the jacks could be protected with some tin foil. It's there to raise the temperature of the PCB so that it's not just instantly sinking the heat from your iron and probably wouldn't melt those jacks even if it was set to "10". It's no hotter than a reflow oven.
@@willej78the jacks probably aren't rated to survive reflow oven temperatures anyways though. And the jacks would be closer to the heating element than the PCB itself that's making it more difficult. I don't disagree that having a pre heater would help a bit but I recently did a very similar thing and it was quite difficult to prevent the components on the other side from melting and still achieve any sort of meaningful preheat.
An alternative option is using a hot air gun aimed at the same side your soldering on held in place by an indicator armed with a clamp or something similar
@@MarkFunderburk Yes indeed, hot air pencil in one hand, iron in the other! This is a technique we use a lot on the boards we rework where I work, most of the time with them on a preheater too.
Another great video . How about a shop tour some time to show how much space you need to have to set up equipment and allow for work flow. Maybe some advice what you started with and you most used and valuable piece of equipment.
Excellent execution on all fronts, stable functional, simple, but also properly engineered to last.
I think the only thing I would consider changing, is select an ENIG PCB finish, so it's more tarnish resistant, and insulate the back of the banana jacks, since a finger could theoretically curl in behind and touch those in a moment of panic or something.
One thing I've played with these type of low-run boards is going with very thin PCBs and doing my own sandwiching. If I'm going to pay for 10 boards, but only need 1, I may as well sandwich 5 of them and get some beefy combined current carrying capacity. It doesn't necessarily multiply that well, and it comes with its own design challenges (if you think 2oz copper takes a lot of heat... imagine trying to get 10 combined layers in there), but it can be an interesting solution
That's a good idea. The stud on the back of these jacks barely penetrates one 2mm board, so maybe not for this project, but in general, that would be a great way to increase rigidity--especially if the boards are clamped at multiple points.
very cool, great idea James !👍👍
Nice job James. This increases the versatility of you lab scope considerably.
Thank you for going through the thought process as always 🙂
Last time I have done a pcb on jlcpcb was a couple of years, but now seeing all their options is mind blowing...
(@ the end) This is the part where you get out the thermal camera to see what's heating up.
I sometimes find that a really good rework flux can make working with lead free solder much easier. I often use AMTECH RMA-223-TFU(UV), down side its a sticky messy flux. So a ultra sonic wash, or considerable time with isopropyl alcohol and a brush. I was introduced to it for BGA soldering and smd rework. Though I know they make versions that are easier to cleanup. But I haven't needed to replenish my stock.
I used a Kester #951 no-clean flux pen. It's great for wiping down stuff like these banana jack terminals, but it flashes off a little too quickly to be great for rework.
I liked the look of the low jacks better than on the side, but I can see one advantage of the side: the wires will hang over the test equipment you have below as is. They're more out of the way on the side...
3d mouse makes the fusion work look so smooth! nice project, very simple yet very educational!
ok - over complicated - i did same: wrapped wires around lugs and used washers and screws done in 5 minutes - however - fun to watch and complain about! keep em coming!
Measuring across the output terminals with the calipers ('shorting' the output) gave me the willies (even though of course you had the output safely turned off). Usually if I'm measuring terminals etc, I'll use my junky plastic calipers - they're usually sufficiently accurate but won't short out my batteries when i measure how long a buttontop 18650 battery is. You can guess how I learned that lesson...
This is an electronic load, so they're inputs.
And lab equipment is always short circuit protected, it's used by students in schools you know.
There is a reason why it has these binding post.. Because you are supposed to use thick gauge wires for this and not banana jack measuring cables which are not designed for this purpose.
This is why 90% of these DC Loads have these posts. Used to be a time that companies would not have to think about such things but in this era where people try drying their wet dogs in the microwave (yes I know this is an urban legend but it explains best what I mean) they have to make sure or get sued.
I find it curious that they sell a 30A power supply (SPS5041X) with standard banana jack binding posts.
@@Clough42 It says right on the front of that unit between the banana jacks ... 10A max. If you want the 30A you have to use the MUCH bigger screw terminals in the back :)
Same reason :)
Although your design is fairly rigid, I wonder if using the entirety (almost) of each side of the PCB as a single trace (e.g., bottom side negative, top positive) would increase the rigidity a bit more. I'm not sure if the capacitance would interfere with the operation, though.
Don't think it would make much difference. Plus standard banana jacks are only rated to 15A anyways.
Great finished product, the cf nylon print really made it look sleek.
Grate work.
Beautiful result, elegant even!
It turned out looking and appearing to work great! Thanks again for sharing James!
I'd please like people like you to design all the products I have to use. If that makes the products more expensive, I'll just buy each one 50 times to save money. ;-)
Hi james
Great project, you’ve given me some good ideas thank you Joe
Nice work. I did something similar with my Siglent except with 2 inputs and a toggle switch to select.
I would have made the traces wider or even flooding the board. The copper is just etched away so it shouldn't impact cost. There is a free program called Saturn PCB Design for doing PCB calculations. Oh and the 15 amp calculation is very conservative.
Good job.
Thanks mate, another fantastic project and video. I do enjoy your side projects into the electrical side of things!
I love this UA-cam channel so much that I decided to move to Idaho. From California 😉
Great video James! I've been slowly developing my F360 skills and got so much out of watching your design process. Thanks for doing what you do. I'm a fan.
That's a satisfying bit of design, elegantly implemented. I wonder why Siglent didn't just counterbore the binding posts with a 4mm hole down the centre. I know that this wouldn't have given the 19mm (3/4") spacing but would have probably been sufficient for most applications.
I've been wondering the same, but frankly looking around the market only BK Prescision seems to have accounted for that. Neither Rigol as a manufacturer on the same level (though they have the sense terminals on the front, which is nicer in a lab environment), nor Keysight, nor Tektronix as a premium manufacturers have that either. The reason is probably simply because most banana jacks are not rated in the same range as the electronic loads themselves, though there are quality ones that are rated for 1kV/32A, they are usually shrouded as well. But as a manufacturer that is always kinda dodgy depending on the market you supply, even if you put some stickers or labels on it.
The 19 mm spacing is also kinda pointless anyway. I think that only really makes sense if you want to use BNC adapters like here, though I frankly have no idea why I would want to do that. BNCs are typically not great for power connections and given the load is rated up to 150 V it seems kinda dangerous conceptually for something that has one side always exposed (well I know there are shrouded BNC, but they are quite rare). The only other thing comming to mind with 19mm banana jack spacing are some thermo coupler adapters for DMMs.
As for the siglent, I think the SDL10x0-y series is kinda due for an overhaul anyway, at least comparing it with other stuff that clearly has a more modern look and feel to it. Maybe they will at least think about the sense terminals in a future overhaul of the design. But I wouldn't mind if they flat out steal the BK Prescision Model 8510B knobs. ;)
Edit: Ironically the BKP Model 8510B also claims 120A capability, which way out of league for any kind of bana jack on the market. So at least they don't seem to care. But I don't fancy spending 2k+ on a DC electronic load. That used to be something you just build yourself with some power transistors, coolers and a bench multimeter...
I swapped my binding post to accept banana plugs a while back. What I did was easier and works good. Search for 100 amp 6m binding post with banana plug, All you need to do is swap binging post nut. That's if your original binging post are 6M
Adapter looks nice.
I did the same thing with the BJ's centered below the binding posts. Makes them a little higher off the bench than your design. I machined a couple banana jacks from brass rod. They are fastened to the board with M3 brass screws and solder (full high test 63/37 leaded Kester. ) Initially used a big traces then, realized two copper pour areas would have lower resistance with better heat dissipation. Also made a set for my bench power supply as well. Yo China engineers, banana jacks go on 19.05mm spacing!!!!
I finally realized why I enjoy watching your videos so much. You are the Bob Ross of machine shops! :)
There's a good reason why binding posts are seen on mearly alp electronic loads. Its due to the limited current carrying capacity of banana jacks. You can get them that are rated for over 15 amps, but they aren't common, nor standard. And it would be easy to mix up cables in the lab.... and end up hooking up regular banana leads that aren't rated for that type of current
If I need high current, the studs are still there. Incidentally, Siglent makes a 30A power supply with standard banana jack binding posts.
@@Clough42 I guess you mean the Siglent SPS5041X? Well at least the silk screen on the fronts says the front panel is only for 10A. I'm curious if they actually limit it for the front connectors or if you could fry them accidentally.
Beautiful work. I think I would have just spilt the PCB on a diagonal down the center on both sides (why use traces at all?) to minimize the IR loss, but this would only matter for high precision work. I love the CAD explanations. I always learn something.
They are through hole connections he could have just done a full fill on each side too
2 things. Carbon in this form is not conductive at all? Wouldn't you have had the advantage of practically separating your PCB in 2 with copper in order to maximize the surface area for each pole?
Really a great result!
why not custom machine nuts that have the banana jacks built in?
that looks pretty schmick, attention to detail as usual 👏
Can't help but think you could have just made some solid brass M6 to banana jack adaptors on the lathe.
Ha, I've been thinking about making something similar for my siglent SDL for a while. Heck, since I've seen the tektronix one with the awsome knobs that have the safety banana plugs integrated I've been trying to find them any maybe use these, but alas no luck so far. As an alternative I was thinking about something with a stackable 2 PCB solution (including some screw terminals to wire 2 cheecky wires along the bottom for 4 wire measurements to the back), but I always held off because I was kinda worried about insulation. Your solution is quite nice though and would seemingly fix my insulation concerns as well. Great projet idea.
Correction: It's not Tektronix with the awsome knobs, it BK Prescision Model 8510B. Way too expensive for my use cases though.
A full 3d scan isn’t required?? I don’t even know who you are anymore 😂
Side note most banana jacks have horrible resistance especially at currents over 1A
Great video with a classy outcome!
Um, I’m sure you iterated through this, but is there any potential for conduction through the carbon fiber rilled nylon? I couldn’t rightly see enough detail on my phone to catch any consideration included.
Many people are asking this question. I can't measure any conductivity in the material.
You could have gotten more power rating if you exposed the traces and let them get some of that sweet hasl action. It'll thicken em up and reduce their resistance for free.
Nice Design I love using fusion 360 !
Gosto muito da qualidade dos vídeos . I really like the video quality!
Done!
Does it matter much how you connect to an electronic load? I have access to a number of Sullivan decade boxes from the 1950s and 60s and they don't have 4mm connections, just a plated brass stump and screw. I cut a 4mm test lead in half, then strip and screw the bare copper down super-finger-tight. That's good enough for two wire use. For four wire, I put the P terminals on the brass stump and get the residual resistance Sullivan put on the plate over half a century ago. I will add: these are 0.05% boxes, and meet that spec today.
Has anybody tested the electrical resistance of the BL PAHT-CF? I know plenty of other PA12-CFs have surprisingly low resistances, but I haven't seen it listed anywhere in their published data.
I have. With a 100MΩ multimeter and the probes forced into the surface of the material, 1mm apart, I read open circuit.
@@Clough42 Glad to hear it! I get worried when manufacturers don't bother to mention electrical characteristics on their datasheets 😀 Does your voltage drop change at all with the cover on versus off?
Carbon fiber is conductive, btw! Might be good to know in this application.
That seems logical, but I've never seen a carbon fiber 3D printing filament with any measurable conductivity.
I wonder how much carbon FIBER is actually in this stuff. Maybe just carbon something.
The issue is that the fibers are not continuous and they're surrounded by plastic.
Absolutely amazing attention to details, also i didn't know the trick with board quantity at jlc (btw you should sell those boards)
This really is one of the best engineering channels on youtube. Amazing work. I am curious what you think about the infosec issues with the bambu labs printers. Everybody says they are great, but I can't bring my self to rely on their fog to make it work. I'm about to pull the trigger on a Qidi Max-3.
I just noticed you have a i-fast review which has most of the same features. Would you still go for an i-fast at the lower $1700 price point, or would you go for the max-3? Seems like the heated chamber means they can do similar things, seems like you are trading speed/kipper for dual head/linear rails.
Sweet!
Love these videos. Why not use fusion PCB design space?
Is the carbon fibre content at all conductive? Might not be the best material to bridge across an electrical connection?
Carbonfiber for something ment to be an insulator? An odd choice. I know the 3d printed stuff isnt anywhere near as conductive but still not sure its the best filament for that application.
Hi James! I really learned a lot from this video. Thank you. Here's a follow up idea and a request. I was wondering if you might be interested in providing some basics tutorial, in your elegant way, about making/ordering/specifying simple PCBs like this, KiCad, and PCB providers. I am pretty fluent in Fusion 360 but have never used KiCad but do have some basic electronic and electrical knowledge. I have never ordered or configured any PCB's. It's likely that I'll need to use PCB's in a way similar to you have here, in that the parts will be more of a standalone object without complicated circuits. I would love to know more about KiCad, why/when it's beneficial as opposed to Fusion, and what files should be exported/used. You mentioned KiCad, Fusion, and the PCB provider's website would've required some additional work that you chose not to do. What are the considerations for this that someone like me should be aware of? Thank you for all that you do and show us!
Well engineered James! As usual. Hope your employer realizes that in your day job.
Not sure if anyone mentione that, but I guess for extra current rating you could have stacked two PCB on top of each other. Would add rigidity also.
Very clever! I am intrigued by how you have the Rigol and Siglent stacked - commercial product or something you whipped up for your 3D printer?
Oh wow, I would have been furious designing the board from the dimensions of the 3D-model, and then find out they needed to be fit with a hammer. That's not cool from Pomona!
Did I miss an explanation of why you didn't just make longer nuts that you can plug a banana jack into? EDIT: I guess that wouldn't work for the 3/4" spacing double plugs.
There’s always money in the banana sh..jack🤣
Trying to understand where a centre-centre distance of 30mm comes from when you measured 30mm across the outside of terminals. If they're 6mm in diameter then wouldn't the C-C distance be 30-(2*1/2*6mm) = 24mm?
He zeroed the calipers when they were at c:a 6mm after measuring the terminals. So you're right, the actual measurement was 36mm.
James, if the fixing pads had not connected the central pad would they be insulated and not require the shroud? Also if you flip a 2nd board will that give you 2 pairs of terminals?
I have never used Kicad but have used EAGLE, now called Fusion electronics. If you are using Fusion 360, why not use Fusion Electronics that is already included with F360? What are the advantages of using Kicad over Fusion Electronics when you can iterate back and forth between MCAD and ECAD seamlessly?
I was just thinking the same thing, it could that you are used to one application and its mach simpler and faster to use fhat one.
For the adapter I think I would have just made a plane on one side for one terminal and a plane on the other side for the other terminal
Have you considered using fusion electronics and binding it to your model so that the two work together?
Is the carbon fibre reinforced print conductive?
I'm just guessing but I think the price goes down because it fits on a whole number of boards so there's less setup and work for them.
Super nice. But I don’t get why you offset the terminals to the left instead of centering them under the two posts?
I'm guessing the rubber casing would get in the way there.
Seeing as carbon fiber is highly conductive, I trust you have previously verified that the filament doesn't produce conductive parts? ❤
Just plot the price per board for a whole bunch of options to see the curve.
It's not continuous. I suspect it's either a glitch in the pricing algorithm, or it's filling up a panel.
What's the resistivity of the Carbon Fibre PLA?
It's nylon, and it's not conductive in any way that I can measure with a 100MΩ multimeter.