Author Topic: Potting a pcb?  (Read 520 times)

garfo

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Potting a pcb?
« on: May 23, 2020, 07:16:49 AM »
Hi guys, I am making a couple of circuits and I'm trying to find out what people use to coat the back of the PCB for circuit protection?
These circuits are designed to be onboard and I'm worried that having the pads exposed could bring problems.
What would be a good and cheap method to coat the back of a pcb?
 I have tried Araldite and Locktite Plastik. Both of them don't seem to be the way to go.

bcalla

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Re: Potting a pcb?
« Reply #1 on: May 23, 2020, 07:51:58 AM »

Matmosphere

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Re: Potting a pcb?
« Reply #2 on: May 23, 2020, 08:11:45 AM »
Or old fashion electrical tape.


Another thing you could do is put some mounting holes on the board and use these. They work very well in my experience.

https://www.amazon.com/Adhesive-Standoffs-Height-Offset-0-6x0-6/dp/B00R4ZT1FY

garfo

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Re: Potting a pcb?
« Reply #3 on: May 23, 2020, 09:14:38 AM »
How about Liquid Electrical Tape?

https://www.amazon.com/Star-brite-Liquid-Electrical-Tape/dp/B0000AXNOD
This looks like what I'm looking for!!!! thank you so much.
[/quote]

garfo

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Re: Potting a pcb?
« Reply #4 on: May 23, 2020, 09:15:53 AM »
Or old fashion electrical tape.


Another thing you could do is put some mounting holes on the board and use these. They work very well in my experience.

https://www.amazon.com/Adhesive-Standoffs-Height-Offset-0-6x0-6/dp/B00R4ZT1FY
This will be a commercial product, hopefully, so electrical tape is not an option. There is a mounting hole on the bpard already. But, I feel better if the pcb bottom is coated.

gordo

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Re: Potting a pcb?
« Reply #5 on: May 23, 2020, 11:52:22 AM »
Bugg has a cool chunk of pcb shim over at PedalPCB.  I take heat for this but I never use anything.  I butt the pot legs up with the PCB and if it's screwed into the chassis and the legs aren't bent (or holes aren't out of alignment) it won't touch the back of the board.  If it's sitting over a socket or anything with long pins I trim them, but in well over 200 years of building (okay THAT's a slight exaggeration) I've never had a problem.

The only issue would be flying leads or long pcb's that might sag toward the footswitch.  Even when Laffing Dog was still in business we never insulated anything.
Gordy Power
On lockdown outside of Chicago

Matmosphere

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Re: Potting a pcb?
« Reply #6 on: May 23, 2020, 11:56:10 AM »
Why not just do board mounted pots? For a commercial product Id be reluctant to seal it with anything because it would make repairs difficult.

Willybomb

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Re: Potting a pcb?
« Reply #7 on: May 23, 2020, 07:28:01 PM »
I just use double sided foam tape.

davent

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Re: Potting a pcb?
« Reply #8 on: May 23, 2020, 08:36:53 PM »
If i'm using standoffs i just recycle some of the hard clear plastic from a bubble type hang to display package. Cut to the size of pcb, holes for the standoff screws to go through, tough, flexible, clear and free.
dave

Tracked this down form an old post when i was using photobucket, might show, might not...
http://i216.photobucket.com/albums/cc305/davent/IMG_5142_zpsc55acc53.jpg
« Last Edit: May 23, 2020, 08:44:13 PM by davent »
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