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Hello all,
I'm new to distilling. I've read quite a bit of the info on this site and it is great. I can't find info to a recent problem. I ran a sweet feed wash through my pot still and everything went well until I was cleaning the copper column and noticed a silver greasy film in the column. I was concerned it was lead, but don't think it is for the following reasons;
The amount is too large? It would be strange to collect that much lead all inside the column.
Lead would sink, right? Not rise into the column?
I don't think it's from the solder as I used lead free.
There shouldn't be any lead also as I followed this design: http://homedistiller.org/equip/designs" onclick="window.open(this.href);return false;" rel="nofollow
Only it's a pot still, Stainless pot, stainless sink drain and the rest is copper with the exception of one brass "lead free" fitting connecting the column to the condenser. There is a brass collar that holds the drain in place, but that's outside the vapor path.
Thanks in advance for your help.

if its lead you put it there,no other way for it to git there.its more likely flux that is not cleaned out yet.

Not sure which brand of sweetfeed was used but is it possible there was something in the feed? Did you distill with grain in the boiler?I know some of the feed comes with pellets in the mix, maybe something used to bind the pellets collected in there? It's a stretch but who knows?
Sounds like Dunder may have it nailed, though. My flux always turns kinda brown not gray. I have seen solder paste that has that gray color, what did you use?

Thanks for the replies. I think your right, something in the sweetfeed. I tried a different kind that has some pellets, oats, corn ect. I also remember that I changed the take off from the column to 45 degrees before it hits the condenser. I think that is helping clean things a bit more and leave deposits in the column. I read on here some where it also helps the purity.