Can you cut a carbon seatpost?

[mjw_byrne]

Originally posted by RC2
So do you let the glue dry before re-inserting the seat post into the frame?

Most definitely! You don't want to end up gluing your seatpost into your frame.

 

[RC2]

Originally posted by mjw_byrne
Most definitely! You don't want to end up gluing your seatpost into your frame.

That was actually a joke. Making light of the rocket science involved in cutting a piece of carbon fiber. Not a moon shot, but pretty close!

 

[tyler_derden]

Try a cut-off wheel on a high speed dremel tool. It will cut the tube and buff the edges at the same time. You can also use it to cut cables and jackets, and almost anything else you can imagine.

As mentioned before, don't breathe the dust- epoxy dust and carbon fiber bits are not good for one's lungs. Wear a mask...

TD

 

[CanAmSteve]

Here's an excellent tutorial I found http://www.easycomposites.co.uk/Composites-Tutorials/How-to-Cut-and-Shape-Carbon-Fibre.aspx

 

[Bob Ross]

So 3 or 4 of y'all have emphatically stated "never grease a carbon seatpost!" or something to that effect.

As someone who has been greasing the carbon seatpost in his carbon-framed bicycle semi-religiously for the past 7 years, I'm curious what the downside is.

It's perhaps germane to note that when I bought this bike in 2006 the "conventional wisdom" was that you should grease a carbon seatpost, and it was only a couple years later when carbon assembly paste started to appear in bicycle shops that the "conventional wisdom" changed to mirror the advice in this thread.

Is my seatpost gonna assplode when I hit the 8 year mark?

 

[CanAmSteve]

Not really sure what other commenters meant, but one problem is with carbon-to-carbon lack of friction. that is, a carbon seatpost in a carbon frame will not have that much friction, plus you have to be careful with clamping torque, so the risk of slippage is higher. That's why there is that special carbon paste, which appears to be Vaseline with sand in it I doubt regular petroleum greases have any negative effect on carbon fibre, and in an alloy or steel frame (although I suppose the latter is unlikely) you can torque down the clamp quite hard on the post to hold it.

 

[alienator]

So 3 or 4 of y'all have emphatically stated "never grease a carbon seatpost!" or something to that effect. As someone who has been greasing the carbon seatpost in his carbon-framed bicycle semi-religiously for the past 7 years, I'm curious what the downside is. It's perhaps germane to note that when I bought this bike in 2006 the "conventional wisdom" was that you should grease a carbon seatpost, and it was only a couple years later when carbon assembly paste started to appear in bicycle shops that the "conventional wisdom" changed to mirror the advice in this thread. Is my seatpost gonna assplode when I hit the 8 year mark?

Friction paste is handy on those setups wherein there is difficulty getting a part to stay in place or in the case where someone wants to reduce the torque needed to secure a piece. Downside? What downside? You could bury a CF seatpost in a vat of grease for 100 years, and when the vat was eventually opened up, the seatpost would be ready to use although a bit messy. Of course it is entirely possible that your seatpost will explode. Carbon fiber parts spontaneously explode at about the same rate that humans spontaneously combust.