PCB protection after soldering

[Plexi]

Is there any kind of 'solder mask for apply to the PCB, once they have all the components soldered?

[deadastronaut]

with a diy pcb i always add a quick spray of clearcoat after testing...

and it can be soldered through too if needed. 

[Plexi]

Great idea Rob
I was thinking in some kind of spray enamel

[deadastronaut]

yeah man, works a treat, better longevity on the exposed copper...

i always have a can of clear in my cupboard, useful stuff..

i rejuvinate my little outdoor solar panels  with it when the get crusty..brings em up to new again
instantly..

[davent]

Like Rob was saying, with the clearcoat you can solder right through so i spray a coat on as soon as i clean off the etch mask. Prevents the copper oxidizing and allows me to solder for months on a project without having to clean the unsoldered pads so i can get solder to work.

dave

[bloxstompboxes]

This stuff has been around forever. People have had mixed results with it. It's a similar but cleaner looking result to soldering all over the traces prior to working with the board.

https://www.amazon.com/MG-Chemicals-421-Liquid-Tin/dp/B008UH3V1K

[Kevin Mitchell]

I do pre-solder protection apposed to doing it after. It helps so much. I like to use tinted clear coats.

[temol]

When making a pcb I use uv photosensitive film. I do not remove the film immediately after etching the board but I leave the film as a protection layer. I remove the film just before applying the soldermask or before soldering. With soldermask on the board there is no need for any additional protection.



T.

[davent]

This stuff has been around forever. People have had mixed results with it. It's a similar but cleaner looking result to soldering all over the traces prior to working with the board.

https://www.amazon.com/MG-Chemicals-421-Liquid-Tin/dp/B008UH3V1K

I do have some and tried it on a number of boards. For me really made no difference in preventing oxidation, still oxidized by the time i get around to finishing a project and still required re-prepping the pads to get solder to work.

Clearcoating was so much better and simpler using something i already have on hand all the time.
dave

[EBK]

I use residual flux and slow oxidation to protect my boards after soldering. Seems to work pretty well.   

[Plexi]

Great ideas...thanks!!

I like the tinted clear coat.
Very good looking too.

What about the soldering over it?
Any corrosive smoke, or something?
I've touched cianoacrilate with the solder, and the smoke made me cry a few hours.

EBK, you keep the traditional way 

[R.G.]

If you're getting bare copper boards, try tinning the traces. Solder makes a great oxidation barrier for copper.

The problem is getting a thin, consistent layer. PCBs back in prehistory used to be roller tinned. Anyone who has watched a ski rental shop waxing skis at the end of a day can easily understand it. A large diameter roller rotates in a pan of molten wax. It carries the molten wax up to the top, where a ski is passed over the top of the roller. The roller is maybe 4" wide and 4-6" in diameter.  The PCB makers had a similar setup, but using molten solder instead of wax.

This process isn't used any more on commercial PCBs, and there aren't any diy roller tinning setups I know of, in addition to them being hideously dangerous.

However, you can tin boards with a tinning tool. This is a cylinder of metal (a pipe will do) with a handle T'd out of the middle. The cylinder ( that is, a chunk of pipe ) is heated by a propane torch through the middle hole until the cleaned outer surface can be fluxed and tinned itself with solder. To tin a board, you get it really clean, all over the copper, then paint it all with liquid flux. Then heat the tinner to soldering temperatures, lay a length of solder on the PCB, and push the solder over the board with the hot tinning iron. The iron melts and spreads the solder as a liquid, and ensures correct temperature and a thin layer ... er, after you've developed the manual skills to do this. Plan on killing a few "learner" boards.

[Plexi]

This morning I've used the lacquer w/dark tint I have for outside woodwork.
I'll see how it goes.

BTW: I've found that my cats urinate in all my paint cans and depot.
What a nightmare...