News:

Forum may be experiencing issues.

Main Menu

how do you keep pot shells from shorting out your board?

Started by randall, December 10, 2013, 01:11:08 AM

Previous topic - Next topic

randall

I am closing in on finishing a Nautilus, and I notice the pc mount pots are very close indeed to the circuit board. I wonder what is the preferred method for making sure they don't short out the board? A non-conductive sheet of material placed between, perhaps?

Stomptown

I would say the best way would be to get some dust covers for your pots if you are really worried about it. It will solve two problems for the price of one!. You could also slip a piece of paper between the pots and the pcb. Or you could tape the back side of the pots (I would recommend using 3M blue painters tape.

FWIW, I would not be too concerned with the nautilus pcb shorting out on the pots. The middle pot is positioned lower than the outer pots and it should make the pcb sit like a table top on top of the three pots.

In case this is your first time using pcb mounted pots, I would also recommend mounting the pots in the enclosure before soldering them to the pcb. This way you can make sure that the pcb is not in contact with the pots and you will not put stress on anything when you box it later. If you slip a piece of cardboard between the pots and the pcb you can get the pcb a little higher and this will make it even less likely you will deal with shorts. Just check that your electrolytic caps are not too tall to fit in the enclosure in this case. If you are using a 1590BB it will be tight if you are using typical electros...

davent

Not pcb mounted pots but i used some recycled transparent plastic (bubble pack ?) between the board and pot backs. Bit thicker then purchased transparencies but much thinner then those Alpha covers which have caused problems in the past being too thick.



dave
"If you always do what you always did- you always get what you always got." - Unknown

If my photos are missing again... they're hosted by photobucket... and as of 06/2017 being held hostage... to be continued?

Matt

Matt

Stomptown

Quote from: davent on December 10, 2013, 02:37:23 AM
Not pcb mounted pots but i used some recycled transparent plastic (bubble pack ?) between the board and pot backs. Bit thicker then purchased transparencies but much thinner then those Alpha covers which have caused problems in the past being too thick.

dave

That should work great! Another option is to make your own pcb mount pots. All you do is solder excess component leads (thicker the better) onto the solder terminals and then solder those to the pcb. Works like a charm!    :)

alanp

Ice cream containers make excellent shims to go between conductive things that are not supposed to conduct to each other.

Tip Top Hokey Pokey has the best toan. Orange Choc Chip also sounds good.

Electrical tape also works well. A square patch on the back of the pot will do it :)
"A man is not dead while his name is still spoken."
- Terry Pratchett
My OSHpark shared projects
My website

jimilee

Quote from: alanp on December 10, 2013, 03:44:07 AM


Electrical tape also works well. A square patch on the back of the pot will do it :)
This.
Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

midwayfair

double sided foam 3M tape (or heavy duty variants).

Also keeps the PCB from moving around.

DutchMF

I usually slip a bit of the foam IC's are stuck in between pot and pcb, works great.

Paul
"If you can't stand the heat, stay away from the soldering iron!"

Vallhagen

Quote from: DutchMF on December 10, 2013, 11:55:49 AM
I usually slip a bit of the foam IC's are stuck in between pot and pcb, works great.

Paul

Be careful, this material can be conductive!

**

I myself use insulating tape or cardboard from... not icecream but cornflakes packs:).
Yes i still have Blüe Monster pcb-s for sale!

...and checkout: https://moodysounds.se/

DutchMF

Quote from: Vallhagen on December 10, 2013, 12:18:05 PM
Be careful, this material can be conductive!
Seriously? Never would have thought that! Any way to test this?

Paul
"If you can't stand the heat, stay away from the soldering iron!"

muddyfox


Yeah I was just about to say that some foam is actually conductive. Haven't seen any myself but have read enough about it to not use any scrap I find lying around...

Vallhagen


Quote from: DutchMF on December 10, 2013, 01:40:03 PM
Quote from: Vallhagen on December 10, 2013, 12:18:05 PM
Be careful, this material can be conductive!
Seriously? Never would have thought that! Any way to test this?

Paul

Yep, all serious. Its easy to measure with dmm/ohm-meter. Just stick the test leads into the foam.

Cheers
Yes i still have Blüe Monster pcb-s for sale!

...and checkout: https://moodysounds.se/

pickdropper


Quote from: midwayfair on December 10, 2013, 04:04:03 AM
double sided foam 3M tape (or heavy duty variants).

Also keeps the PCB from moving around.

This.

I prefer 3M VHB.
Function f(x)
Follow me on Instagram as pickdropper