Cutting down circuit board

[Diamondj421]

Greetings everyone!
Super noob here. I had an Ibanez Soundtank TS5 TubeScreamer but the pedal enclosure broke. I wanted to perform a few mods and then place it in a new enclosure that I have. Unfortunately the circuit board is slightly too large. I have a good amount of experience with PCBs that have the thin traces that are all the same width but this style is new to me. I feel it's safe to assume that the shiny, light green areas on the board are the traces since the leads of every component is soldered along there.If that's true, I'd have to trim the board down to the traces to make it fit which means they'd touch the enclosure. Again, I don't know much about these boards, but given what I do know about electronics, that seems like a no-no. Is there anything I could do to make this work or is it not worth my time/energy? Sorry if this is a dumb question but again, Im just starting to learn about this. 

[vigilante397]

Welcome to the forum

Is there anything I could do to make this work or is it not worth my time/energy?

Bigger enclosure You're correct that the lighter green areas are copper traces, and if they touch the enclosure wall they will definitely short. Obviously it's not impossible to rehouse a pedal, but I would recommend finding one with a bit more space to work in.

[antonis]

Hi & Welcome..

As I see PCB, left vertical dimension is a ground plane..
(except upper unsoldered pad..)

I'd cut/chop that dimension till PCB fits into the enclosure with unsoldered pad track isolation (via a laquer) but I'm notorious for my slipshod builds..

[moid]

If you are only cutting the absolute minimum off the board (sensible) then I would consider putting insulation tape around the inside of the enclosure in case the board connects with the box when you stomp on it. Good luck, I would not want to cut a PCB for fear of cracking it... I would also aim for a larger box... hmmm is the enclosure deep enough that the PCB would fit if if rotated around the axis that runs the length of the enclosure?

Edit: if you do cut it down, cover the PCB in masking tape (painter's tape in US?) first - this protects the traces from whatever you are cutting with when you invariably slip, and sometimes it helps to minimise any cracking along the cut line.

[Digital Larry]

Can you look through binoculars backwards at the PCB, then pick it up with some tweezers and put it in the enclosure?  That's how we used to put elephants into bottles.  Seriously though, I would just get a larger enclosure, unless:

a) You're interested to see whether you can recover the board after breaking it, since I'm pretty sure what you're planning to do will at least cause a temporary cessation of its normal function.

b) You don't put much value on your personal time - because the cost of a larger enclosure can't be more than about $15.

[duck_arse]

also welcome.

I'd personally cut the enclosure in half, making sure not to cut thru the footswitch mounting hole. then I'd extend/widen the box with some form of metal covering/plate for the crack. but I'm like that.

[aron]

As a beginner you can never have a too big enclosure when starting out.

[Elektrojänis]

I'm pretty sure the coppertrace on the left edge does not really have to be that wide. It was just made that way to fill a board of standard dimensions for that pedal series (It is usually a good idea to fill the empty spots on the board with a ground plane.)

Usually it is not that critical if the ground trace touches the box as the metal enclosure should be connected to the ground anyway. However it is usually the best practice to only connect the box to the circuits ground only from one spot to avoid ground loops, which can cause hum and noise problems. However, in many pedals the ground is connected to the box at least in two spots without any issues.

The trace on the right side is probably the power. Be very carefull that it doesn't touch the box. If the box is properly grounded and the trace witht he power touches it, there will be a short circuit for the battery (or power supply if you use one), and stuff will get hot and star smoking.

So... If that was mine, i would trim enough from the left side that it would fit really nicely, and probably insulate all the sides from the box somehow... Probably by sticking electrical tape or gluing some plastic on teh sides of the box. That however would require some further modifications to the stuff in the top left corner. That one now empty pad is probably for the postive battery wire. It would probably need to be removed and battery wire would need to be connected to the rightmost pad of the external power connector. You would need to be very carefull not to short that one to the box. And I'm not sure if that power connector will fit. It si possible that it woild need to be removed from the board and connected with some wires.

That being said... It might be more difficult project than it looks like. It is doable, but mechanically challenging. Bigger box would be an easier option, but even then you could have trouble with getting the potentiometers sit right on the top of your new box. Also bear in mind that the widht of the box might be even narrower in the top of the box than in the bottom (if you consider the visible side on your pic to be bottom).

Oh... One more thing... I would probably do the trimming by filing/sanding the edge. I would probably take a sanding block and some sandpaper and run it along the edge or maybe hold the sandpaper on a table and scrub the edge of the circuitboard to it. That can feel slow, but I'd consider it to be the safest method and least likely to crack the board. Many of those are practically paper that has been infused with some kind of epoxy resin or something and the do crack quite easily. 

[Diamondj421]

Bigger box would be an easier option, but even then you could have trouble with getting the potentiometers sit right on the top of your new box.

I was thinking that too. I have some Alpha pots that I was going to use. I'm half tempted at this point to just get a TS9 or TS808 kit. Honestly, this was more or less something to do. I found it in a drawer and thought "What the hell? Why not get this guy up and running?" I build a lot of my studio gear but $300+ for a preamp/EQ/compressor kit is a little too rich for my blood these days. Figured this would be something to tinker with/fulfill my urges to solder. Are there any kits out there that anyone would recommend?

[Elektrojänis]

I was thinking that too. I have some Alpha pots that I was going to use. I'm half tempted at this point to just get a TS9 or TS808 kit. Honestly, this was more or less something to do. I found it in a drawer and thought "What the hell? Why not get this guy up and running?"

Using some pots that can be mounted on the box and wiring them offboard would make it easier to fit teh board you have in to the box you have.

If the board is just sitting in your drawer, you could try it and try to make all the holes to the box so you can still use it for the kit. (If the kit board fits in it.) That way if you end up breaking the board, you can just order the kit and build it in to the same box.

[Ice-9]

It could be done, but you would lose the trace all down the right hand side which would mean reconnecting this track with some wires. It looks like you are wanting to fit this into a Hammond size 1590B. If that is the case then just get a Hammond size 125 and it will fit with not mods.

[anotherjim]

If you cut the edge back exactly right, then file the copper edge back at an angle you end up with it fitting snugly by the pcb insulation material and the copper can't then ever touch the enclosure. That's how I fit stripboard too - bevel the copper back.

[Diamondj421]

If you cut the edge back exactly right, then file the copper edge back at an angle you end up with it fitting snugly by the pcb insulation material and the copper can't then ever touch the enclosure. That's how I fit stripboard too - bevel the copper back.

That actually makes a ton of sense! I probably should've asked this already but what's everyone's preferred method for cutting a board?

[MrStab]

I can't offer any links, but there's a niche of people who do this with old consoles, and they all challenge each other to shave as much off of boards as they can. Try looking up "portable N64".

[EBK]

I can't offer any links, but there's a niche of people who do this with old consoles, and they all challenge each other to shave as much off of boards as they can. Try looking up "portable N64".

Ben Heckendorn is a nerd hero of mine.  I have a book of his, teaching how to cut down old gaming systems to make handheld gaming systems.

https://www.amazon.com/Hacking-Video-Game-Consoles-ExtremeTech/dp/0764578065

[davent]

If you cut the edge back exactly right, then file the copper edge back at an angle you end up with it fitting snugly by the pcb insulation material and the copper can't then ever touch the enclosure. That's how I fit stripboard too - bevel the copper back.

That actually makes a ton of sense! I probably should've asked this already but what's everyone's preferred method for cutting a board?

Diamond cutting disc and a Dremel, facemask not optional.

[Ice-9]

Just having a laugh.

[toneman]

Might I suggest a belt sander?
https://www.popularmechanics.com/home/tools/g36813678/best-belt-sanders/
A bench sander like #3 will remove epoxy pcb real quick!!!!!
Looks like U have plenty of room on both sides to sand off.
If U lose the trace on the right, just use an insulated jumper and hotmeltglue it so it wont wag around,
What moid said about the edges is a good idea. If the board is tight.
Can use hotmeltglue to secure pcb also.
If U use a power supply to power it up, u can check current draw to see if its normal.
Have fun!!!!