Eurorack Synth Noodle Toaster v2

I thought that would be an issues, so specifically bought shrouded headers so that I would always plug the cable in the correct way round. Seems like a simple thing to just have marked on the silk screen.

That’s good to know, I’ll check my heat sink and adjust it accordingly. Still haven’t decided what to do about the case yet, but the MI eps file seems less than optimal with its layout of the various pieces. Did you adjust it before sending it off to Ponoko…?

I know someone with a laser cutter, and there is one at the local Makespace, but I’m not sure how much acrylic I need to buy, as I’m not sure how savage I can be with editing that eps file. If was making any more, especially if they were some sort of frosted purple/violet top and dark grey sides and base, hint hint, I’d buy one in a heartbeat…

I might have time to do some cases in the next month or so, pandemic reduced service still here, I’ve got 10 colours of opaque cast acrylic, not sure what’s down at the workshop at the moment, might be 3 or 4


I suppose the only question is this, do I solder the LEDs and Thonkiconn jack sockets in without first attaching the top panel so they all line up…?

it’s generally not a huge problem, I have lower standards than you by the sounds, I soldered mine up first then cut a case later, didn’t have to adjust jacks or leds, there are one or two fairly tall electrolytics which you’ll need to solder on their side if you want to use a case, towards the top right corner somewhere

I would highly suggest waiting to solder in the LEDs and jack sockets. The switches fit pretty snug so there’s not enough movement for you to worry about throwing it off IMO. You will need to put the electrolytic’s on the top on their side if you want to use the MI case.

The only thing that I modified on the MI case file were the graphics and labeling of things. For example, it makes more sense to me to have the IN/OUT arrows facing in the opposite direction of what they have on the file. I work in Adobe Illustrator almost everyday so changing the file around was quick and easy for me. If you are going to adjust the case file then realize that you don’t have a lot of room for error if you want to keep the joints pretty snug. Make sure you check your math and/or print out an outline of it on a piece of paper and make sure it all fits together before sending it to get cut.

Lastly, the thickness of your acrylic will make a difference in how your encoder fits. I think 3mm is too thick personally.

OH and there is one other important thing to note. There are 2 trimpots on the top of the board. However, the MI file that I had did not have holes cut out so that you could adjust them from the top. You would need to open the case, which is not practical. I didn’t realize this until AFTER I had my case cut. I ended up drilling the holes in after the fact. It pissed me off though because I would have liked to have had them labeled on the lasercut top. :angry: Why? Well because even right now I cannot remember what the hell they are adjusting! :rofl:


Acrylic, schmacrylic.

Tested and working!

My adaptation of the MI board. I have extra PCBs. There are some issues — the Euro power header footprint is reversed, and there’s one pad floating that needs a wire to connect it to ground. And TBH I haven’t yet tested the MIDI but it’s fine right? Since there are errors and it’s not my own design, just a slight revision of the MI original, I don’t want to put them up on Tindie but if you want one at $10 postage paid (US only, pay via Paypal) DM me. Note this is larger than the MI original (213x133 mm), and the MIDI and 1/4" jack footprints are changed (MIDI works with a jack I got on Amazon and should work with Kycon KCDX-5S-N, Digi-Key SKU 2092-KCDX-5S-N-ND; audio jack footprint works with a jack from Tayda, SKU A-1122.) Cigar box not included.


Amazing fit! 20 chars

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Love a cigar box project. Hard to come by in the UK now. Great fit too.

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After a month of sitting on my hands, Sunday just felt like a day to get on with some soldering. I cleared my desk, got everything out and cracked on. After a few hours of listening to podcasts, I was finished, more on that missing Thoniconn later:

Like most things in life, when you’re done, you look back at all the stress and anxiety and wonder what all the fuss was about. The build was pretty straight forward, although I did encounter a few issues along the way. I have learned a some lessons that I’ll have to mitigate for next time I’m soldering lots of components in one go.

I started with the resisters, then the diodes, then continued through all the other components in height order (ish). It go more difficult after soldering in the DIN and jack sockets, as my Stickvice doesn’t have a long enough rod for me to mount the PCB length ways. I should really have left these two till last, but I didn’t.

The main issue with the soldering was keeping all the components flush to the PCB. I put all the resistors in at once, flipped over and soldered away. When I flipped back over, one of them had moved and wasn’t flush. This happened more than once, various capacitors slide down, the power socket slide down, and one of the IC sockets is leaning to one side. It would appear that just bending the legs of various things isn’t enough, so I may have to invest in a bigger ball of Blutack, putty or something else.

I had two real issues, both of which were related to getting component legs through the board, as my close up eye sight isn’t great, and those holes are small! I put the big DIP-40 Socket in, and about three quarters of the way through soldering the legs, realised that there was a leg missing. I flipped the board over to discover that it hadn’t gone through the hole and was bent along the top of the PCB. I managed to pull it out the top of the socket, carefully straighten it, and push it gently back in, then finished soldering the rest of the legs. I was quite pleased I didn’t throw a wobbler, I just calmly sorted it out.

I may have used a few choice words with trying to fit the Thoniconns though, [insert favour deity here] they were fiddly. I half broke a leg of one of them, but managed to get the rest of it in and soldered, but one the the back legs completely broke off another one. It wasn’t like I was being slap dash, it looked like it was all lined up, and felt like it was aligned, but it just didn’t want to go in straight and bent off. So I’ll have to put another Thonk order in, but I may wait till I’ve got a few other things needed purchased.

The only other real issue was I accidentally soldered the shrouded header on the wrong way round. I knew where the -12V pins were and thought I was putting it on correctly, I should maybe have checked with a cable in the socket, just to be doubly sure. Thankfully I managed to gently prise the shroud off, turn it round and push it back one. So thanks to @analogoutput for that suggestion, as it saved a messy desoldering attempt.

Once the shroud was sorted, I plugged my Eurorack power breadboard helper and all the LEDs lit up. I confirmed that I was getting +/-12V and 5V and breathed a sigh of relief.

Things that still need to be finished; getting hold of a case, that missing Thoniconn, bolting the heatsink to the 5V regulator and calibration, for which I need that missing Thonkiconn.

Fingers crossed, that tomorrow I can actually put it to use and power my breadboard, as I finally get back to working on my triple SSO with resonant active low pass filter. :+1:


Just to prove that my stripboard was actually working, I used the multimeter to measure the voltages:



If you’ve ever watched one of Quincas Moreira’s (SynthDIYGuy) build videos, he starts by putting resistors and diodes in place, and then soldering them from the top. I’ve been doing the same for a while now and I like it; it’s generally a lot better than trying to navigate the forest of resistor legs underneath, and of course it keeps them from trying to escape like your guy. It can be a little problematic sometimes, like when one resistor is positioned with its pad right next to the center of another resistor. You learn to leave that second resistor out until you’ve soldered the first one.

After soldering from the top Quincas flips it over to clip the legs and to touch up any joints that look dodgy from that side. When I started using his technique, that was about half of them. I’ve gotten more generous with my solder quantities since then and I usually have only a few to touch up.

Everything else you usually pretty much have to solder from the bottom, but there’s not as many caps and transistors as resistors and diodes so that’s okay.

On this board I did solder the switches from the top, just because I found the switches (from the BOM) didn’t really get sufficiently through the holes for me to feel good about soldering them on the underside. It would’ve been tricky if I’d already done the LEDs, but I’d noticed the problem ahead of time and held the LEDs off until after the switches.

As for shifting components, I’ve gotten pretty good about soldering a single leg of each socket, header, etc., then checking its position before doing the rest. But I went a bit too fast on the LCD module and it ended up a bit crooked. No big deal though.

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I totally forgot to mention some of the issues I had with soldering, it was late when I posted that. I have watched at least one of his videos, and I did touch up a couple of the diodes from the top side, as I wasn’t happy with them.

For the most part the soldering was pretty straight forward and easy, but I really struggled with a few of the components, and just couldn’t get any solder onto the pad. I’m not sure if it was my technique, or just the fact that the pads were really small, but even using a flux pen, I could get plenty of solder on the leg, but nothing on the pad. You’d move on to the next component and it would solder easily, but going back it was still a battle to get anything remotely looking like d decent joint; it was quite frustrating.

I’ve sort of convinced myself that it’s the bevel tip, and as I move along the board, I’m occasionally not finding the correct angle for some reason. I might get the proper bevel tip at some point and see if that improves matters or not.

As for IC sockets and whatnot though, yes, I totally need to just do a leg or two, then check my work. It’s the first big PCB I’ve soldered up in about thirty years, so it was inevitable a few things wouldn’t go smoothly. I’ve got one of the those DSO Shell oscilloscopes turning up in a few weeks, so I might try soldering the resistors from the top and seeing how we get on.

Do you have a ground plane in your design? Were they pads connected to ground and hence the ground plane? If so, do you have thermal reliefs for those pads?

I have trouble soldering those, as the ground plane sucks up the heat. You can either bump up your iron temperature for it, or what I usually end up doing is try and tin the iron, rest it on the pad without letting it touch the component leg for a little bit first to try and heat the pad/plane first, then go for the component.


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Not my design, but now you come to mention it, I did struggle with some of the LED legs, which were on the ground plane, and had tiny solder pads. :thinking:

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I had an unusually large number of bad solder joints on mine, and I don’t know why.

Well, the optoisolator where I soldered one pin as described above and then never actually did the other 7, that one I know what went wrong…

I hear people talk about the difficulty of soldering pads on the ground plane but it’s something I rarely if ever notice. Maybe I’m running my iron hotter than they are.

But then again, most of my bad solder joints on this were the LEDs — 5 of 6 didn’t light up at first — and now that you mention it, I think they were all on the ground side.

Also the ground side of the push switch terminals on the encoder, but also on the non ground side of same.

All were among the last things I soldered, so maybe I was getting too eager to finish.


the jacks can vary marginally, if one doesn’t fit easily it can be a question of rooting around until you find one that does, or smoothing the corners of the pins with a file to ease it’s passage, glad it mostly came together without any bother :slight_smile:

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No takers, not too surprising I suppose — but if the price is stopping you, make me an offer…

if only it was outside the US, id swipe one up real fast haha

DIY synth Module Tester PCB's (new version 2) ships from the UK…


hek yeah :)))))))))))

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