> Just found that we had 2 Scrub Free cleaners under the sink. Neither
> has sulfamic acid listed on the label, Tilex and one called Scrub
> Free.
>
> Took a 6" x 18" copper clad blank that had some blemishes and tried
> each of the scrub free cleaners in a 4x6" strip. Both did show a
> change in the color of the copper but neither took out the blemishes.
> Washed off the board and dried it, then tried Tarn-X. That fully
> cleaned the board and no blemishes remain.
>
> I think the Tarn-X cost around $5. The label says to use rubber
> gloves (the scum cleaners don't) so for my money, I will stick to the
> Tarn-X. There should be enough in the bottle to last me for many many
> boards. Maybe if I could find a Scum Cleaner that 'does' list
> sulfamic acid on the label it would work better then those that don't,
> but Tarn-X is working so I'm happy.
>
> I do wonder if the other 2 cleaners that Bill mentioned, Zap! and
> Restore4, might be better but so far, I have not been able to find
> them.
>
>
> Thanks for the tip WB. It might help those overseas that don't have a
> source for Tarn-X or the others.
>
> Wayne
>
I looked at the Household products database and found tarn-x is 3-5
sulfamic acid but also contains Thiourea which may help cleaning.I
found that Lime Away has < 11 percent sulfamic acid acording to the
MSDS sheet. Tried some on some BAD copper and all the dark brown areas
turned that nice reddish color you want. The black and green areas
appeared to clean up with some scrubbing. This stuff is readily
available. Assuming the sulfamic acid is what you want there is a
product called Aqua Mix Sulfamic Acid Crystals available at Lowes that
is a 99.5 percent pure sulfamic acid crystals. Don't know what it
costs yet. But Lime Away does work and it doesn't have a lot of exta
stuff in it you may not want.
Keith