Seat post struck in frame

[PaintedDesert]

Painted Desert: just to know, how did you hacksaw the post out of the frame? How did you hold the saw blade? Did you use a blade holder or just hold it in your hand? Also, did you have to make a single cut, 2 cuts or more?

I just held the blade in my hand, wrapped in some cotton. I made 2 parallel cuts going down as deep as I could without fear of cutting into the frame itself. Then stuck a screwdriver between frame and seatpost and gently pried the seatpost to the inside until I could grab it with pliers and pull it loose. At some point it said "pop" and came loose entirely.

It wasn't fun.

 

[Retro junkie]

Re:

I’ve read somewhere, probably on here that as you ride a bike you create a very small charge which over time causes the alloy post to in effect weld itself to the inside of the frame.
Never did find out if this is true or not. Grease, and plenty of it is what’s needed. Once you have the post out obviously

 

[Graham_hkr]

Re:

It's a phenomenon called 'Galvanic reaction' basically a build-up of aluminum oxide that makes it hard to remove.
If you want to educate yourself on all the details of the electrochemical process, you can Google it!

Thanks for watching! :facepalm:

 

[alainbriot]

Yes plumbers freeze spray is available in the US. There's also this which is specifically for bicycles:

https://www.amazon.com/gp/product/B00AC ... ZF2T4P42H9

Anyone who tried it?

 

[Peachy!]

Yes plumbers freeze spray is available in the US. There's also this which is specifically for bicycles:

https://www.amazon.com/gp/product/B00AC ... ZF2T4P42H9

Anyone who tried it?

Not tried that specific product, but I have frozen an alluminium post before... I turned the frame upside down to put it in a bench vice and it dropped out!

 

[coomber]

Re:

Freeze spray I have used with success.

Had a karate monkey with aluminium seat post stuck solid. 2 weeks of penetrating oil daily and nothing.

Removed (highest up the seat tube) bottle mount screw and stuck 3/4 of the can in. Just pointed it with the straw nozzle thing as far up into the tube to get the seat post frozen cold from the inside. Just kept spraying.

Wear gloves. Seatpost went white with cold. Twisted it out in about 2 minutes. Was tight but moved out and once it moved an inch slid out easy.

Would highly recommend.

 

[The History Man]

Nobody has mentioned the elephant in the room yet.


Bubble bubble..........

 

[2manyoranges]

Re:

There are five methods

Indeed galvanic reaction between two metal types.
Or just rust if steel in steel.

Drowning- Soak in plus gas for a fortnight - seldom works

Brutality - crush post to a big flat at top - get scaffolding pipe on it and twist - generally scary but often works

Laceration - of your hands as well as the seatpost - new hacksaw blade, with wrapping, great care and patience, always works, but is unbelievably tedious

Arctic blast - using freeze pack - can work brilliantly or not at all

Time travel - go back to when you put the post in, but this time install it with grease.

 

[Retro Spud]

Or as THM has alluded to there is a sixth method Caustic Soda

 

[mk one]

or a seventh, heat.