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Electronics => Beginners => Topic started by: cdev on May 24, 2020, 01:33:09 am

Title: What do you use to coat boards to protect them?
Post by: cdev on May 24, 2020, 01:33:09 am
I'm looking for a general purpose coating thats easy to apply and can be removed to repair stuff and solder to it again somehow if you need to.
Title: Re: What do you use to coat boards to protect them?
Post by: tautech on May 24, 2020, 01:42:54 am
Solder through PCB lacquer aerosols are the way to go.
Can't recommend a local one for you without a country identifying flag.  :P
Title: Re: What do you use to coat boards to protect them?
Post by: cdev on May 24, 2020, 01:48:29 am
I'm in the US.
Title: Re: What do you use to coat boards to protect them?
Post by: chriva on May 24, 2020, 01:52:30 am
How generic do you want to go and in which quantity are you planning to coat boards?


I've.. *erhm* stolen some of my missus' nail polish from time to time for use on one-off prototypes. Works surprisingly well...


If what you're doing is in any way meant for production or customer use, I'd buy the real stuff tho.
Acrylic coatings are quite easy to remove but not resistent to fuel vapors.
Silicone and Urethane are just PIA to remove so avoid those
Title: Re: What do you use to coat boards to protect them?
Post by: cdev on May 24, 2020, 02:03:23 am
Thank you for that tip, Thanks to my better half I now have some NYC "long wearing" clear nail enamel, extra shiny top coat. this looks like it should do the trick!

Wonder what its RF properties are? I guess that is likely to be important, still its likely better than leaving it for the moisture in the air to corrode.

How generic do you want to go and in which quantity are you planning to coat boards?


I've.. *erhm* stolen some of my missus' nail polish from time to time for use on one-off prototypes. Works surprisingly well...


If what you're doing is in any way meant for production or customer use, I'd buy the real stuff tho.
Acrylic coatings are quite easy to remove but not resistent to fuel vapors.
Silicone and Urethane are just PIA to remove so avoid those
Title: Re: What do you use to coat boards to protect them?
Post by: tautech on May 24, 2020, 02:09:37 am
I'm in the US.
Consider showing a US flag.

This is the stuff I use for protecting newly etched PCB's and touch up on repairs.
https://www.jaycar.us/circuit-board-lacquer-spray-can/p/NA1002 (https://www.jaycar.us/circuit-board-lacquer-spray-can/p/NA1002)

This MG product from Amazon should be quite similar:
https://www.amazon.com/MG-Chemicals-422B-340G-Silicone-Conformal/dp/B008O9YGQI (https://www.amazon.com/MG-Chemicals-422B-340G-Silicone-Conformal/dp/B008O9YGQI)
Title: Re: What do you use to coat boards to protect them?
Post by: richnormand on May 24, 2020, 02:25:37 am
This has worked well for me.
Title: Re: What do you use to coat boards to protect them?
Post by: tautech on May 24, 2020, 02:30:28 am
This has worked well for me.
Can you solder through it ?
Title: Re: What do you use to coat boards to protect them?
Post by: vk6zgo on May 24, 2020, 03:11:37 am
When I worked at the hearing aid place, when we did rework on the Cochlear stuff (the external processor, not the implanted part! ;D), we used a product which was sold for marine use.

It seamlessly merged with the existing coating, but unfortunately, I can't remember the name, or details.
Title: Re: What do you use to coat boards to protect them?
Post by: pickle9000 on May 24, 2020, 03:18:57 am
This has worked well for me.
Can you solder through it ?

You can solder through it. It's thin on application and can glue components in place (surface mount) if they are close enough to the surface of the pcb. Hot air works as long as its not too heavy a coat.
Title: Re: What do you use to coat boards to protect them?
Post by: pickle9000 on May 24, 2020, 03:36:10 am
Here is a link to MG Chem conformal coatings.

https://www.mgchemicals.com/products/conformal-coatings/ (https://www.mgchemicals.com/products/conformal-coatings/)
Title: Re: What do you use to coat boards to protect them?
Post by: Syntax Error on May 24, 2020, 02:46:34 pm
Ad-hoc, I use Electrolube branded 'APL' acrylic protective layer. It's in a nail brush bottle and can be removed if needed with a solvent. It claims to be solderable through, but not having tried, I cannot vouch for this. Proven use in protecting the circuits of outside solar lights.
Title: Re: What do you use to coat boards to protect them?
Post by: Siwastaja on May 24, 2020, 04:54:51 pm
Nothing.

Use casing to prevent dust accumulation.

If you have some specific environment in mind, specify the requirements first. It's nontrivial.

If you think you need some "general-purpose" protective coating, most likely you don't need any. If you need one, be a lot more specific.
Title: Re: What do you use to coat boards to protect them?
Post by: chriva on May 24, 2020, 05:16:08 pm
RF black magic is definitely not my area of expertise so I'll be honest and say, _I DON'T KNOW_. :)
I'd imagine it's fine if it's only running at a couple of hundred Megahertz but don't quote me on that. Ask the real gurus just to make sure
Title: Re: What do you use to coat boards to protect them?
Post by: richnormand on May 24, 2020, 06:14:18 pm
This has worked well for me.
Can you solder through it ?

Once dry, yes.
Title: Re: What do you use to coat boards to protect them?
Post by: madires on May 24, 2020, 06:31:29 pm
Kontakt Chemie FLUX SK10.
Title: Re: What do you use to coat boards to protect them?
Post by: Kasper on May 25, 2020, 06:24:20 am
Here is a link to MG Chem conformal coatings.

https://www.mgchemicals.com/products/conformal-coatings/ (https://www.mgchemicals.com/products/conformal-coatings/)

Thats where I go too. They have a good variety and descriptions of the different types.
Title: Re: What do you use to coat boards to protect them?
Post by: cdev on May 27, 2020, 03:39:45 am
I am probably going to end up with the MG stuff, I have used their contact cleaner, tuner spray, etc.  although the shiny hardness of the nail polish has some appeal as far as verifying coverage.

Sprays I wonder if there are holes. (oh, actually, the MG chemicals spray has a "UV indicator" , so thats good)

"Contains a UV indicator for optical inspection"

Also,  I wonder what the best procedure is with boards that have corroded a bit? I have some boards that have grown green stuff (cleaned now) in high humidity areas. It was on copper that wasnt coated with anything. Once its gently cleaned off with Qtips and IPA, and dried off.

My hope being that a coating stops further corrosion! 

But I guess no after the fact treatment can't work miracles *LOL*.