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Damn indeed. UV cure resin is brilliant at invisibly repairing cracks in perspex. Unlike super glue it remains clear when cured.
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Great tip! Unfortunately, I dont have any. So superglue it is…
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All’s well that ends mostly well. The crack is worse than the paper screw up, but I’m not going to sweat it
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Not bad! I have two acrylic sheets that I bought long ago and never got around to using them because I am afraid that I will mess them up. I think I’d be happy if mine ended up like this!
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Would not Class it as dumbassery, just unfortunate. 
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Not sure what happened here. This was my first attempt in producing gerber files from a kicad project (the Hagiwo VCO with mods by @clarionut ) I guess the bottom layer was not rendered at all?
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There’s not supposed to be silkscreen on the bottom in that design, but there should be pads and traces:
Presumably you produced the Gerbers in KiCad? If I follow the instructions at How to generate Gerber and Drill files in KiCAD 8? (if you’re getting these fabbed at JLCPCB) I get these files:
RP2040VCO-B_Cu.gbl
RP2040VCO-B_Mask.gbs
RP2040VCO-B_Paste.gbp
RP2040VCO-B_Silkscreen.gbo
RP2040VCO-Edge_Cuts.gm1
RP2040VCO-F_Cu.gtl
RP2040VCO-F_Mask.gts
RP2040VCO-F_Paste.gtp
RP2040VCO-F_Silkscreen.gto
RP2040VCO-NPTH.drl
RP2040VCO-NPTH-drl_map.gbr
RP2040VCO-PTH.drl
RP2040VCO-PTH-drl_map.gbr
All should be included in the folder you compress and upload to JLCPCB. If you use the KiCad Gerber viewer you can verify the back copper layer which is in RP2040VCO-B_Cu.gbl:
If all of that looks like what you did and your Gerber files look correct, then maybe JLCPCB screwed up — contact them.
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Indeed, I messed this up. I downloaded the file from JLCPCB and the B_* files are missing. I also have the Edge_Cuts file as .gbr instead of .gm1 Not sure whether this is a mistake as well. Looks like I am going to bin this and make another order.
This is bad luck.
I always look at the top ond bottom of the boards in JLCPCB’s Gerber viewer after uploading a project as a check that things looks OK -
There shouldn’t be any problem having Edge_Cuts.gbr rather than .gm1. I’m still using KiCad 7 and (apart from the .drl file) all the files have the extension .gbr.
All the best for the next try!
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There’s an option in the Gerber exports for which extensions to use (at least in version 8, and I’m pretty sure it was there in 7). JLCPCB recommends using the Protel extensions.
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Thanks for that - I thought I’d read JLCPCB’s instructions for generating files, but clearly not! Fortunately they can successfully process the files I’ve been sending them, but I’ll try to do it properly in future…
It looks like I had the B_* files generated in the project folder in my computer but, for whatever reason, I did not include them in the .zip file that I uploaded 
I am thinking that I might made the mistake during the back and forth when JLCPCB returned the order twice because it had “no board outline” (I remember that as I generated new files in the same folder, I had to delete the previous ones… easy to f up). And while I typically check the files with their gerber viewer, sometimes it doesn’t work (it gets stuck in “loading”), so I probably didn’t bother with that.
Many thanks to both @analogoutput and @clarionut ! I will give it another try. In the meanwhile, I will try my luck with an AVR VCO that I can quickly put together in stripboard. That is, after I finish the half built module I have on my desk!
once you have done it a couple of times it will be natural.
The design Checker will also help with board outline issues , these often show up when doing 3d view in kicad too.
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Does this count… I thought it was a hardware issue.
I’ve been revisiting this currently 8 voice bi-timbral polysynth the Polykit-16, mainly trying to fix up the performance implementation so it can actually be used in bi-timbral mode properly. Anyhow one of the issues was that the sub oscillators and the triangle waves were quite intermittent, in such that the triangle sounded like a saw until all 8 voices had been rotated through and the sub oscillators sometimes didn’t sound on the first key presses. This has been driving me mad for some time.
I rebuilt the sub oscillators tonight and still the same issues, they sound better, but still do not sound immediately sometimes, also going through test presets I saw the same behaviour. So eventually I put a scope on the input to the sub oscillator from the saw output and what do you know, when I change patches etc the sawtooth drops to a very low frequency causing the sub oscillator to glitch until it sees a reasonable frequency range to convert from saw to square, same for the triangle waves, they have to recover from that initial very low frequency and sound raspy until they receive a higher note.
Seems my allnotesOff that I send on patch recall to the DCO modules was killing the waves dead.
Still this has given me time to fix other issues on the synth like synch of the LFOs in whole mode etc.
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I just spent 4 hours wondering why the led displays wouldn’t illuminate, first of all I had wired the 7 transistors as EBC bases when in fact they were ECB pinout, ok that’s easy, quickly rewired, still no displays, in fact even worse everything is blank. Swapped the board with a previous build, displays are ok.
Swapped all transistors from 2SA1015 to 2N3906, still the same, suspect my Chinese bought 74LS38 chips, I have 3 variants and all of them the same results. Eventually pulled the good display board from my AX-80 rack build and swapped the LS38 to be sure and test. Still the same.
Started measuring earth’s on my working board to the faulty board, strange, my working board doesn’t have the 7 transistors connected to ground, they are connected to +5v. DOH!
Cut the ground link and connected to +5v and everything works. What a waste of an afternoon and 7 binned transistors.
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i think we can forgive you that one…
the second one, well i am sure we have all tied something to the wrong rail once, or twice or …
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I was wondering why my VCO had no square and saw output. Looked at the board and saw this. Classic dumbassery.
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lol been there done that .
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