Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => AmpTools/Tech Tips => Topic started by: tubesornothing on May 29, 2011, 06:36:45 pm

Title: Struggles with old liquid tin
Post by: tubesornothing on May 29, 2011, 06:36:45 pm

Hey all,

I have a board where I laid down 1/4" wide copper traces to connect eyelets together - to serve as the ground bus.  I thought I would coat it with liquid tin.  I had an old bottle from MG Checmicals on the shelf.  So I shook it up, painted it on and it came out all black.  I can solder to it at all.  I tried rosin and even plumbers flux to remove the black - but no luck.  Any suggestions on how I can get this stuff off the copper and the eyelets?  Its about 30 eyelets so it would be a bunch of work to drill them all out.

thanks

ToN

Title: Re: Struggles with old liquid tin
Post by: bigugly on May 30, 2011, 11:30:59 pm

try ferric chloride. just put an ounce or so in a plastic bowl and stand your board straight up in it and use a foam brush to apply the solution.

Title: Re: Struggles with old liquid tin
Post by: PRR on May 31, 2011, 09:38:20 pm

Try vinegar and salt. Takes skuzz off copper-bottom pots.

Title: Re: Struggles with old liquid tin
Post by: tubesornothing on June 05, 2011, 10:52:57 pm

Thanks guys, I will give it a shot.