How to protect untinned PCBs?

[hodad]

I have some old (70s era) pcbs that were never tinned. These are functioning cards--components installed, everything working--but it'd be nice not to have to worry about the traces corroding. Can they be tinned as is? Is there another way to protect them?

 

[RuudNL]

Spay the copper side with flux or plastic spray.

 

[RATMNL]

any (easily available in the netherlands) specific sugestions?

 

[JohnRoberts]

http://en.wikipedia.org/wiki/Conformal_coating

conformal coating is used on mill spec boards to protect them

JR

 

[hodad]

Is conformal coating that funky smelling, slightly sticky stuff I've encountered in old avionics?  If so, does it smell any less icky than it used to?

 

[JohnRoberts]

I don't recall it having any smell, but the last time I worked on mil-spec stuff was back in the '70s and it was new gear, not old.

JR

 

[Timothytitus88]

I know it is not in Europe, perhaps there is something similar....

http://www.altronics.com.au/index.asp?area=item&id=T3086

I think the difference between this and normal lacquer is that it is fine to solder through, so rework is not a problem.

I sprayed some on some boards a good 15 years ago, and the copper is still shiny, so it does do the trick, But it will not last forever in the can (so don't buy in super bulk quantities)

I would not think that tinning was possible on a populated board. I am still keen to try some of those tinning crystals on some of my freshly etched boards, but finding a small economic quantity in OZ seems to be impossible. Ill bite the bullet one day and get a bottle from RS

Cheers,

Tim

 

[Andy Peters]

Spay the copper side with flux or plastic spray.

Flux can corrode the traces. That's why you clean the flux after assembling the board!

-a

 

[Andy Peters]

I have some old (70s era) pcbs that were never tinned.  These are functioning cards--components installed, everything working--but it'd be nice not to have to worry about the traces corroding.  Can they be tinned as is?  Is there another way to protect them?

You can buy solder mask material in a bottle. Something like this, maybe.

-a

 

[Timothytitus88]

Bit if you solder mask all over, and something needed replacing, or a dry joint needs rewetting down the track, would solder mask not make it difficult?

Cheers,

Tim

 

[ricardo]

I know it is not in Europe, perhaps there is something similar....

http://www.altronics.com.au/index.asp?area=item&id=T3086

I think the difference between this and normal lacquer is that it is fine to solder through, so rework is not a problem.

+1 to the stuff you can solder through.

 

[gyraf]

I always used "SK10" Flux Protective Resin, spray can, protects PCB and makes soldering easy.

Jakob E.

 

[RuudNL]

Spay the copper side with flux or plastic spray.

Flux can corrode the traces. That's why you clean the flux after assembling the board!

I never had problems with that!

I always used "SK10" Flux Protective Resin, spray can, protects PCB and makes soldering easy.

I do exactly the same!

 

[therecordingart]

Acrylic lacquer or Humiseal. Both are solderable and work great.