Modding best practices.

[danwojaz]

Hey Everyone,

I have a few questions regarding pedal modding best practices. Usually when I modify a pedal, I just change values of components and use the existing pcb holes, but sometimes, a mod requires components to be soldered to a pot/ switch off of the pcb and wired to another component on the board. what would be some best practices to make it more professional and prevent issues?

1. How do you mount a PCB in an enclosure when the potentiometers do not hold the pcb down.
2. how do you add resistors/ capacitors/ other components on a switch or potentiometer and make sure the components dont short out on the enclosure/ bottom of the board.

 

[Brett]

what would be some best practices to make it more professional and prevent issues

Ideally, you'd have a PCB with all components needed for your modifications being board-mounted. If you're running wires from here to there inside of an enclosure, the best way to prevent mishaps is to secure the wire/component. Strain-relief is a good idea for wiring robustness, but it's not always practical if there aren't good mounting points for tie-downs. Not endorsing his circuits themselves, but take a look at how Pete Cornish handles wiring for examples of road-worthiness. Every point of movement is a potential point of failure. This example may be overkill, but his pedals are often used as a reference point when questions like this come up.

How do you mount a PCB in an enclosure when the potentiometers do not hold the pcb down.

There are options for PCB standoffs, even when boards are not designed for them. I've seen them at GuitarPCB (I think?), but something like these: https://www.thingiverse.com/thing:47369

how do you add resistors/ capacitors/ other components on a switch or potentiometer and make sure the components dont short out on the enclosure/ bottom of the board.

Take another look at that picture above. Creating a secondary board (if there's enough additional circuitry to warrant it) will be more reliable than just hanging components off of random odds and ends, as long as that secondary board is secured out of the way of existing circuitry. @Robert offers a few different "satellite" boards that kind of serve this purpose. There are other boards out there that have diode clipping options on a switch, cap/resistor selections on a switch, etc. that can be used for mods. You could also just use a small piece of prototyping PCB and secure that to an open area inside the enclosure.

Here's one such example: https://www.pedalpcb.com/product/6-10-5/

I hope at least some portion of this was helpful. Good luck!

 

[andrewsrea]

If I have it correct, you are asking about 1.) sister boards (your addition to an existing pedal) and 2.) adding in-series components to existing PCBs?

If so @Brett had some great suggestions.

For #1, I've been as unsophisticated as wrapping the sister board in blue painter's tape (will not turn to goo in 5 years), placing a self-sticking wire tie anchor on the pedal enclosure and using wire ties to secure the tape and the board to the pedal.

For #2, once again blue painter's tape and wire tie wrap, sometimes silicon, sometimes double-stick foam tape (a great insulator).

 

[Passinwind]

Hey Everyone,

I have a few questions regarding pedal modding best practices. Usually when I modify a pedal, I just change values of components and use the existing pcb holes, but sometimes, a mod requires components to be soldered to a pot/ switch off of the pcb and wired to another component on the board. what would be some best practices to make it more professional and prevent issues?

1. How do you mount a PCB in an enclosure when the potentiometers do not hold the pcb down.
2. how do you add resistors/ capacitors/ other components on a switch or potentiometer and make sure the components dont short out on the enclosure/ bottom of the board.

1: I often use Nomex sheet or fish paper to wrap the PCB, then double stick gel, foam, or velcro to secure it:



Those are just temp wraps secured with 3M electrical tape, which allow me to do mods to each board without even removing them from the pedal, or replace individual modules pretty painlessly. This works especially well with SMD parts, I can often swap a 1206 resistor in less than five minutes. Once the prototype is working as desired I glue up the wraps, which are inexpensive and easy to replace if ever needed. Definitely not the most professional looking builds, but they've proven to be utterly reliable and unless I'm selling one I couldn't care less.

 

[darwin999]

All the above comments by @Brett @andrewsrea and @Passinwind are excellent. I'll just add that if my mod includes something that is box mounted (e.g., a switch), then I've often used a small piece of perforated prototyping board to create my own daughter board with holes drilled for that switch (and then soldered to it so the board won't move around), and then run wires from it to the main PCB.

 

[Passinwind]

All the above comments by @Brett @andrewsrea and @Passinwind are excellent. I'll just add that if my mod includes something that is box mounted (e.g., a switch), then I've often used a small piece of perforated prototyping board to create my own daughter board with holes drilled for that switch (and then soldered to it so the board won't move around), and then run wires from it to the main PCB.

In the pic I posted above you can see some of the many utility daughtercards I've had made over the years. They come in very handy for components that I might want to swap out during the prototyping phase, and this is one application where OSHpark really shines on cost effectiveness. It also makes reusing pots and switches a bit more painless in a lot of cases, plus it's a great way to get started on doing your own PCB layouts.

 

[jcpst]

I did a build not too long ago where I used 3M dual lock for the relay boards. At one point I had to make a change to the offboard wiring, it was handy to remove it and then just click it back into place.

Also, if you can use even just one of the pcb mount points for the pots, that will hold the board in place and you can have the rest of the pots wired wherever you want.