Titanium frame seat posts

[swannymere]

Does anyone have any ideas about what type of material is best used for a seat post in a titanium frame? I'm sure i've read somewhere about 'galling' occurring when using a titanium seat post in a titanium frame, is there some type of grease i can use to prevent this; copperslip maybe?

 

[d8mok]

I use copper slip in all my Ti bikes for both BB and Seat post.

I also give the post a wiggle once every so often and remove the BB once in a while as having had the experience of a seized BB in a Ti frame it’s not something I’d like to repeat.

 

[ishaw]

As above. I think there is also a product called ti prep or something like that which is supposed to prevent galling.

On that topic, I thought galling was when two different materials reacted and corroded together. Ti on Ti doesn't fit that, though I could be wrong. Another factor is whether your ti frame has an alloy shim inside the post as many have. Not sure any of mine do (I do seem to have more than is healthy), though I have seen that some of my frames did have them when I've come across other builds.

 

[Tootyred]

Both aluminium and ti suffer from galling more than steel. Its a quite complex thing, but basically material transfer between two things starts the process. The material can be alike. Its worse on moving wear surfaces, but can happen almost instantly on tight insertions or nut and bolt threads, especially in high strain. We had problems with it when we mandrel bent tube steel sections as one bit....

To stop it in a seatpost, i would suggest that making sure each surface is as smooth as possible and that grease or copper slip is used. Copper has a high resistance to galling.

Wow, who thought i would need that 40 years after the class finished

 

[retrobate]

As above. I think there is also a product called ti prep or something like that which is supposed to prevent galling.

On that topic, I thought galling was when two different materials reacted and corroded together. Ti on Ti doesn't fit that, though I could be wrong. Another factor is whether your ti frame has an alloy shim inside the post as many have. Not sure any of mine do (I do seem to have more than is healthy), though I have seen that some of my frames did have them when I've come across other builds.

You are confusing galling with galvanic action.

Galling is like cold welding, screw an A4 stainless bolt into an A4 nut without any lubrication and there is a good chance of the thread picking up and if you try to undo it tearing off chunks of thread. It is best to mix the grades of stainless (A2 & A4) to reduce the risk of galling and as others have said use copper slip or neverseize to lube the threads.

Galvanic action is why we get aluminium seatposts seized into steel frames. Two materials with different potentials forming a weak battery, causing corrosion.

Edit. Oops TT has posted while I was typing . What he said

 

[Hotwheels.]

Both aluminium and ti suffer from galling more than steel. Its a quite complex thing, but basically material transfer between two things starts the process. The material can be alike. Its worse on moving wear surfaces, but can happen almost instantly on tight insertions or nut and bolt threads, especially in high strain. We had problems with it when we mandrel bent tube steel sections as one bit....

To stop it in a seatpost, i would suggest that making sure each surface is as smooth as possible and that grease or copper slip is used. Copper has a high resistance to galling.

Wow, who thought i would need that 40 years after the class finished

You knew it'd come in one day.

 

[Hotwheels.]

I recall when buying a Ti Ibis stem bitd they wrote in the blurb to use the supplied steel bolt only and not to upgrade to Ti as it would likely cause galling.

 

[ferrus]

Never had a problem with Ti posts in Ti frames; as mentioned just use copper slip and wiggle occasionally for reassurance