Stuck seatpost? Freeze it out......

[sherlylock]

Apologies if this has been discussed before but I'm so chuffed I've released a stuck post I thought I'd share.....

So....I bought a Pine Mountain frame recently on eBay - it'd been floating around for a while and it had a seized seatpost (I think it originally came from a forum member - I remember seeing it one here at some point?)

Anyway - I fancied a challenge and have never tried to remove a seized seatpost (and have recently witnessed a friend go through the trauma of hacksawing one out).

After a bit of research on Sheldon Brown a few things came to light.....(bearing in mind this is an Alu post in a steel frame)

1. Penetrating oil is near to useless as it wont penetrate the aluminium oxide

2. Using heat is worse than useless as aluminium expands twice as quickly as steel - making matters worse.

So - using the bit of reverse logic on Sheldons site about temperature differentials I thought maybe cooling the inside of the seat post down will shrink it twice as quick as the steel seat tube, allowing it to be freed.

I found a product called "Freeze & Release" by Loctite. £8 a can and it's used for super cooling stubborn fixings to allow them to be undone. I bodged together a longer tube to reach down to the stuck part of the seatpost, accessed through the bottom bracket hole, and released about a quarter of the can contents.

After a lot of twisting with the seatpost in a vice I could see the post wanting to move and eventually, with some more cooling, it let go with a bang.

Once I got it moving I kept twisting side to side. Lots more twisting/creaking combined with pulling the post it finally let go and came out of the frame. WooHOO!!

So for the sake of an £8 can of freeze and 45minutes of frame wrestling I now have a usable frame and seatpost! *smugface*

 

[Bullpup]

Nice one! I wonder if that stuff will work on car brake bleed nipples?

 

[r7ctr]

Well done sir.


I had a stuck seatpost & made things worse by doing the stuff you tried early on but previous owner had cut the seat post too close to frame to get leverage.

So ended up trying to drill it out (last option !!!) but as didn't have a workshop bench to hold steady ended up coming out the frame tube :cry:

 

[Anthony]

Excellent! There are so many people on here and elsewhere whose instinct is to use heat, so they actually take a blow torch to their precious frame and paint, doing only damage. Use brain is a better idea, as you have demonstrated.

 

[sherlylock]

Hmmm....interesting comment about brake nipples - I've got a 205 GTi sat on the drive with a stubborn corroded brake pipe that needs replacing and wont budge - might give this stuff a whirl on it.

My mate resorted to drilling his seatpost and went through the frame. I have seen it done successfully though - guess it has to be done with the utmost care

I've also got a stubborn bottom bracket shell (on Whayne's Orange frame) that won't budge - might be worth a try too.

 

[Matthews]

Wurth do a similar product if you can't get the loctite stuff, or try a CO2 fire extinguisher.
Matthew
Does not do health and safety :shock:

 

[bontyfiend]

You can probably also use it for verruca removal. Bonus!

 

[marc two tone]

very good martin. another '92 marin lives on!

seeing is believing and, a relatively cheap method with no ill-consequence to paintwork etc..

should i adopt your method the local scrap man will be gutted as i will be disposing of frames with stuck posts much less.

 

[sylus]

I know mine shrinks when it's cold

 

[sherlylock]

very good martin. another '92 marin lives on!

seeing is believing and, a relatively cheap method with no ill-consequence to paintwork etc..

should i adopt your method the local scrap man will be gutted as i will be disposing of frames with stuck posts much less.

I've wanted a '92 PM for a while now - there don't seem to be that many around.......

I really want to try freezing another frame now to see if it's repeatable! Not that I need another frame......