Board-mounted pots on a single-sided etch… recipe for success or disaster?

[greysun]

Hi everyone!

I'm etching a few boards as I gear up to finally finish a pretty complex ardiuno-based pedal switcher I've been working on forever - I'm rusty, so need the practice.

One of them is based on the DIYGP Rock Bottom EQ ( https://www.diyguitarpedals.com.au/shop/boms/Rock%20Bottom%20EQ.pdf ), which I based on their schematic. I bought 2 from them, but they ran out and I needed a 3rd - which actually works out because I can add a 6th EQ band with the unused op-amp circuit in the schematic. Its tight, adds more jumpers than I typically like, and a single knob on its own row for volume, but that's okay by me.

I used board-mounted pots for everything. But then wondered if that's a no-no with a single-sided etch. I can solder the pots on the same side without issue, but is the possibility of pulling up copper or breaking the signal paths something to worry about?

Any help is appreciated! Thank you all so much. :-)

[madbean]

You can do it but it can be a pain. The weight of the pots can lift the copper if you are not careful. My advice is design it for PCB mounted, but just used wired pots. That way, if you ever convert it to a manufactured double sided board later you're already perfectly set.

And, obviously do not try to do toggle switched PCB mounted.

[greysun]

You can do it but it can be a pain. The weight of the pots can lift the copper if you are not careful. My advice is design it for PCB mounted, but just used wired pots. That way, if you ever convert it to a manufactured double sided board later you're already perfectly set.

And, obviously do not try to do toggle switched PCB mounted.

Exactly the answer I needed and mostly expected. I have only board-mount pots, but can trim them and use the holes at the top for wires. No switches for any of the boards, so we're all good there. If I ever had boards for this one made, there would only be 5 connectors up top, so not complaining there, either. (but also not making boards later, hehe)

Thanks for the advice! :-)

[aion]

Most EHX stuff in the 70s used board-mounted pots on single-layer boards and they're still going strong. With 6 pots, you've got enough anchor points that no one joint will be stressed, but out of precaution I would recommend soldering the PCB in place inside the enclosure if possible to ensure that it's custom-fit to the enclosure (to account for any slight misalignments in the drilling for instance). As long as you use good-quality copperclad then you'll almost certainly be fine.

[madbean]

Most EHX stuff in the 70s used board-mounted pots on single-layer boards and they're still going strong. With 6 pots, you've got enough anchor points that no one joint will be stressed, but out of precaution I would recommend soldering the PCB in place inside the enclosure if possible to ensure that it's custom-fit to the enclosure (to account for any slight misalignments in the drilling for instance). As long as you use good-quality copperclad then you'll almost certainly be fine.

Those are generally top mounted though, aren't they? Component side, I mean. I was taking about soldering them on the copper side actually.

[greysun]

Most EHX stuff in the 70s used board-mounted pots on single-layer boards and they're still going strong. With 6 pots, you've got enough anchor points that no one joint will be stressed, but out of precaution I would recommend soldering the PCB in place inside the enclosure if possible to ensure that it's custom-fit to the enclosure (to account for any slight misalignments in the drilling for instance). As long as you use good-quality copperclad then you'll almost certainly be fine.

Those are generally top mounted though, aren't they? Component side, I mean. I was taking about soldering them on the copper side actually.

Interestingly enough, I just looked at my stock of PCB material - and I have almost all double-sided board (copper on both sides). Debating if I should try a double-sided etch, but am nervous having never done it... I'm using press-n-peel blue transfer, which I've had success with in the past - I'm a designer by day, so I'm very familiar with registration marks. (I also have access to a cricut maker, but that feels... iffy. hehe).

If I did a double-sided board, do you think that's enough to hold everything in place?

Also, has anyone done a double-sided etch and lived to tell the tale? LOL...

[287m]

You'll be fine. If brownie-cheap-ugly-thin single sided perfboard can live long, why not for pcb? Theyre thicker. If you worry, you can build or buy pcb secure mount for reinforcement. Best combination for odd knob or triangle formation, rarely see if build 4knob or 6knob. Still worry? Build with mounted screw.

Learned this from some session player at my friend cafe.

[aion]

Those are generally top mounted though, aren't they? Component side, I mean. I was taking about soldering them on the copper side actually.

Yeah, that's true, the traces are always opposite the pots. It's a little more rigid that way for sure (and certainly more convenient for assembly).

I'd still say 6 pots is fine as long as you're careful about alignment, but fair warning that this will be really hard to do!