has anyone else had any cross-contamination issues between gold and
titanium???
titanium filings and particles, as with any form of titanium
instantly form an impervious oxide layer on contact with air. That
generally prevents good bonding or wetting by solders, though you can
get a bit of joinint with enough flux. But the bonds are not good.
So if you’ve got titanium particles imbedded in your solder, first
off, like any dirt, it will lead to pits and messy joints. Plus, with
a different thermal expansion rate that the gold, it might lead to
stresses in the joints. And given the very light weight of titanium
grindings and filings will fly around more than will gold, so might
easily get everywhere on your bench, and could easily get onto
soldering pads, into the flux containers, or whatever. And, I’m not
sure, but it might even form a microalloy type of contaminant, as one
can get an almost 24K gold that’s microalloyed with titanium, making
it about the same hardness as 18K, and with some different working
properties too. In general, while larger pieces of titanium (such as
solder pics) should be safe enough, the idea of titanium dust flying
around where your soldering gold, just might not be too bright an
idea, and might well be involved in your problems. Even if I can’t
tell you for sure, it seems clear enough that your own experiment by
using different tools to solve the problem seems a pretty good
indictment of the titanium dust.
And finally, does your boss pay for your tools or do you? Mention to
him that titanium is rather hard on steel tools, dulling burs and
files very quickly. So if he’s using tools he pays for, he’s making
your job harder and slower by bessing up the tools he pays you to
work with. And if, as is often the case, you pay for your own tools,
then get mad and tell him to buy his own damn tools and keep his
hands off of yours, cause he can quickly shorten the life of your
tools by using them on titanium.
You might suggest, for this task, the use of rotary diamond
abrasives, such as the 3m diamond sanding bands. Used with oil or
water for lubrication, the lubricant also keeps down the dust
generation. And he can grind a lot of titanium with those sanding
bands. If he mounts them on an appropriate mandrel fixed to an
adapter chuck for the polishing motor, then he can do his grinding
with that fixed motor safely removing the grindings as well, and
keeping your bench free of the dust. Both Stuller and Rio carry the
diamond sanding bands. with lubricant, they last quite well (I use
mine with platinum, and even with daily frequent use, they last
several months on average. Probably would last even longer if I were
more careful about the lube)
HTH
Peter Rowe