Titanium Frames and anti seize

[Kontact]

Originally Posted by 11.4

I am saying that titanium bottom brackets are not immune to corrosion. But I'm saying that they don't undergo true galling. The example you cite, with the damage at one exposed end, is characteristic of corrosion -- corrosion typically doesn't happen without exposure to air. And while in this particular case it was possible to spin the bottom bracket out, in many cases it isn't and one is trying to figure out how to cut the cup out of the shell (or the seat post out of the seat tube).

Anti-seize does prevent galling better than plain grease but for different reasons -- the metal flakes have a lubricity that allows the metals to slide against each other. The issue here is that what's happening in a bottom bracket or seat post is typically corrosion. Galling occurs as soon as you've applied heat or pressure to the two metals in contact, so you would have a galled and locked up bottom bracket as soon as you had threaded it in. That's not what people typically find. What you find is induced by corrosion over time and that is why the bottom bracket tends to thread in easily when installed but is locked up a year later.

I think it is pretty hard to say when galling happens because very few people install their BBs and then immediately take them out to inspect them. Galling can happen when you insert the cup, remove the cup, or put a load on the cup without it being at full torque. There is no requirement for "heat or pressure" beyond that generated by rubbing two likely to gall metals together.

The thing I am preaching here is that corrosion is bad, but galling is worse in that is has a greater ability to 'cold weld' a cup into place than just the aluminum corroding, because it affects the Ti surface, not just the aluminum structure. Since it is a known issue, it seems crazy to me to not just use a dab of anti-seize. Just not copper anti-seize.