Ti frames & loctite removal

Originally posted by Karl
hi all

I have a frame/BB that required some of the blue (medium)
loctite to get the BB cup to stay in place. I am now having
trouble removing the BB. Loctite says to heat the joint to
325 to dissolve the loctite - anyone know if this is ok for
a Ti (Litespeed) frame? Are their other ways to do it? Will
a lower temp help? I was going to set up my campstove in the
driveway and give the BB shell a steam bath for a few
minutes to try to loosen it up, I have already tried acetone
but it obviously does not get far into the joint.

TIA Karl

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Careful with the heat if the BB cup is aluminum because 325 will definitely kill the temper of the aluminum and might make it prone to stripping.

There is another bad thing going on here and that is oxidation of the aluminum from galvanic action. Yes, even if you used threadlocker, the aluminum is in contact with the Ti, setting up a dissimilar metal corrosion problem. Use ammonia solution to dissolve the oxidized aluminum.

Since aluminum has a higher expansion coefficient than Ti, try chilling the frame to break the bond. You should be able to get it loose with a few pounds of dry ice. Wrap the frame in rags to insulate it, leaving only the bottom bracket exposed. Modify a cheap styro cooler to fit the frame and pack it in dry ice. You can get an even more severe chill by adding alcohol to the crumbled dry ice. Oh, do this OUTSIDE as the carbon dioxide can get dangerously high. At least leave a door open since CO2 sinks and will flow out. Put the dry ice in a towel and hit with a hammer to break. Funnel the pieces into your cooler.

The beauty here is aluminum actually gets STRONGER as it is chilled. Be careful of your wrenches because they get brittle at low temperatures. And as always, wear heavy gloves and safety glasses. Dry ice fragments are quite damaging to your eyes.

Originally posted by Mark Hickey
Weisse Luft <[email protected]> wrote:

>Careful with the heat if the BB cup is aluminum because 325
>will definitely kill the temper of the aluminum and might
>make it prone to stripping.

Not to mention that aluminum expands more than titanium when
heated, so the BB will be even tighter when heated. He might
get away with focused heating of the frame's BB shell and
then rurning the BB out before IT heats up... but I like
your dry ice idea!

Mark Hickey Habanero Cycles http://www.habcycles.com Home of
the $695 ti frame

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Thanks for the addition! I would recommend liquid nitrogen but its a bit tricker to handle. I had a stuck seatpost problem a few years ago and had access to liquid nitrogen...I suspended the frame above a styro Dewar of liquid N2 and filled it so the seat post was immersed. After a few minutes, the aluminum had shrunk and fell out.

The seatpost was trashed from the owner's application of a slide hammer to free it. He even drilled a cross hole and bolted a section of square tube to affix the slide hammer for a second time.

Soaking in ammonia for a few days (steel or Ti frames ONLY!) didn't work.