The 3D Printed Test Fixtures I Use For My Products

I design test fixtures for industrial scale production in automotive electronics, talking thousands of panels an hour, tens of thousands of units. our test kiosks can get over 100K in price stuffed with all sorts of gear from keysight, NI and etc. Our fixtures can range from 10-17K and carry dozens of amps, network communication(s) , fiber optics, camera systems and hundred's of pogo-pins. In a nutshell its exactly the same concept that you presented, just copy pasted a bunch of times lol. you pretty much nailed it

As a Ham, I agree that the foot switch for powering up the rig for the boost board is a workable solution. Another that comes to mind is to find a space on the setup to mount a momentary switch so that when the board under test is seated in the test rig, it closes that contact, that works with the controller to activate a 1 second delay and then trip a relay that gives the board under test it's 5 volts, and the test begins. Optionally have a pass/fail indicator controlled by the main board, and after 3 or 5 seconds of test shows the results (less time if you need less time,) and power down the 5 volts so that you can then remove the board under test. That opens the momentary switch which clears the pass/fail indicator and you're ready to test he next board. (No need to remember to release the foot switch, or if you ever get to the point where you hand off that testing to someone else, train them in switching the power on/off with the footswitch.) Having seen far too many 7-segment LED's with a single segment not working, would suggest adding code to turn on all segments in the display under the LED that shows which button is being pressed, and powering down the rest of the display so that you can verify that each digit in the display is good. I'm aware that since the display does read Clough42, each driver line is being triggered, so any failure in soldering the connections is already tested, but it's always good to go the extra 914.4 mm, right?

Great job as always! The clothes-pin clamp is brilliant. I have a lot of commercial production experience with pogo pins and I would highly recommend using the sleeves to hold the individual pin units. They do get flakey after a while and it's usually much easier to change a pin than a whole assembly. My jigs all use two layers of the same PCB with a little gap between them and the sleeves soldered into both PCBs.

Digispark. I love those little boards. Use them for all kinds of things.

I'm always impressed with the work you do. I'm over here just daunted by the thought of undertaking just one of your many projects and here you are not just doing a bunch of them - but also reproducing them in droves like some sort of electronics rabbit.

Hunh! I've spent the last three days watching this whole series - I've been enraptured. How convenient a timing to be one episode away from the end... only to get rewarded with yet another episode! Brilliant!

James, I’ve been running your ELS on my Atlas 10” lathe with a clear path servo since you first designed it, the system has been flawless from the get go. Thank you for your skills and attention to detail on everything you do. Chuck

I find these videos great for seeing what's possible with resources available to everyday households - domestic industry - keep 'em coming.

Extended pogo pins for testing in linear or arrays normally have ground pins on both ends or all four corners so that ground is always the first to make contact. “Just thought I would mention it”. Or a zener diode on the 3.3 volt input test controller at higher than 3.3 volts but lower than the fry voltage might save the test controller from operator error or floor pedal problems.

Test fixture videos are the best videos! Thanks for sharing your knowledge and testing workflow.

James , short comment regarding PCBA testing - try to not test them on any foam material, especially when you press buttons, you apply stress into PCBA , which can damage some components ( ceramics caps and glass diode's are most critical in this case ) . It can pass your test , but fail later on when this PCBA will be installed into lathe , where more vibration can finally damage components , which have cracks already. Also you have V-cut on the panel - this can also add some failures , in case you test boards before separation as de-penalization is manual. Maybe will be better to de-panelize them first and then test it on some printed fixture ( if you have material with resistance from 1 to 10 GOhm - it will be ideal for this from ESD point ). Anyway - it`s a great joy to see that someone test PCBA similar to production facilities !

I love the concept of being able to make a simplified testjig. I have wanted to experiment with simplified jigs for awhile but never gotten a PCB that was simple enough but have enough challenging tests to do. Some things that came to mind while watching the video. When making a PCB think about how you wanna test it and then put testpoints on the PCB because then you can automate the whole process and eliminate the worst thing which is human errors like looking at LEDS and such. I highly recommend having a relay to power on the device so you can systematically test the device when you are ready and not when the board gets plugged in. When you then make your jig together with a DUT filled with testpoints, just make all testpoints available on the fixture, then you can always make a new bodge that connect the testpoint you didn't want to use initially.

Great video, I really enjoyed seeing your thought process manifested. One idea that I’ve seen and used myself, is to incorporate a micro-switch into the PCB mount, so that when a board is fully seated, it’s depressed and then triggers a relay to turn on power and run the tests. It saves a lot of time vs a foot pedal IME.

Micro computers are just too cool and you've capitalized on their capabilities, shared your knowledge about the project and how to put it all together. You definitely stand in front, on the side, underneath and yes behind. You definitely stand behind your product by not taking for granted third party involvement. Even good intentions need to be monitored. Heck you can be the one who got a bad batch of something or other. So thanks for checking them out and removing all doubt that delivered product has passed its QC Inspector #54 !!

I know to the initiates to the sacred art of electronics this is pretty routine but to us mere mortals it is pure magic. It would be interesting to see the design process of how to use a simple microprocessor to do some simple task. I love electronics but have no idea how one goes about designing something at the breadboard level to do anything beyond switches and LED’s. I think some of your audience may be interested in how one goes about doing this amazing work.

Fantastic video, great info! I've been meaning to make some test jigs for my boards and really appreciate this run-down. Great eye on detail as always - well done!

Wow! This is next level. Great work James.

Fantastic video! I appreciate you sharing these ideas, planning on making some test fixtures as well, so very timely.

Love the red lens added in post. Works surprisingly well.

Awesome video. Look forward to commencing an ELS project with your products and videos