Originally Posted by
howellhandmade
... Handy on the titanium scrap, every place I've visited that machines titanium controls scrap pretty closely. I bought a variable DC power supply which, hopefully, will remove at least some guesswork. Did you start with battery acid before dilution, or a higher concentration? My plan is to use lye to de-smut, dealing with one type of acid bath is enough.
Unfortunately our Ti scrap is rod; not sure there will be enough surface area. Al or Pb will always work.
I used sulfuric acid bought as a drain cleaner from Menards. SDS said it was 85% so I diluted to the required concentration (C1V1=C2V2).
Nitric acid to desmut, diluted from 85% IIRC.
Next time I'll do everything a little better - sand, polish, de-anodize, degrease, desmut. It's like painting - all in the prep. What my trial taught me is that there are no shortcuts if you're picky.