Will heating a Reynolds 653 frame to remove a stuck seatpost

[zhang]

As per the title, I have a Reynolds 653 TT frame which has an aluminium Campagnolo seatpost stuck in it. A well regarded local framebuilder is confident that the seatpost can be removed, preserving both the frame and seatpost and only damaging the paint around the seat cluster. However, a material scientist friend of mine warns that doing so would affect the strength of heat treated steel. Though I'm not sure if Reynolds 653 is actually heat treated or not (I recall that 753 had some very special requirements)

So basically I want a third opinion so I can decide whether I'll remove the seatpost with heat or dissolve it with sodium hydroxide (admittedly better for the paintwork than heat, but also a massive hassle since I'd have to do it myself)

Thanks

 

[Nob]

Re:

I'd avoid the heat issue as this alters the metallurgy of the metal unless your an expert on heat treatment processes & metal make up.

I'm lucky to have access to a machine shop now & in the past so have removed at least two seat post with the use of a vice bolted into the concrete plus 20 ton gantry crane. You can figure the rest.

Other way was radial drill & milled out the seat post.

No damage to the frame what so ever after a good NDT MPI process.

Good luck with yours.

 

[hamster]

If the framebuilder has a 753 licence then go for it. If it is overheated the silver solder would melt anyway.

Expert use of a brazing torch should be fine, but it's not something I would want to do myself in case I overheated it.

 

[M-Power]

Re:

Rampage sells a seat tube saw specifically to cut out seized seatposts. It will take 45mins of elbow grease but its a lot less hastle and mess.

 

[sherlylock]

I've had success freezing a post out in the past - aluminium shrinks/expands twice as much as steel so filling the inside of the seat-tube with plumbers freeze spray allows the seatpost to contract away from the steel frame. You should be able to then twist it free (with the post in a vice)

Have also recently cut a post out using a home-made tool (as per Rampage's method) to hold a hacksaw blade. Obviously you kill the post doing this.

Not sure heating the frame up is ever the right way to go tbh.

 

[Johnsqual]

I've dissolved a stuck aluminium BB cup out of a frame. It works well, but is a horrible, horrible, messy process. Also, the chemical reaction generates a quite bit of heat. Maybe not enough to damage the frame, but something to bear in mind.

For a seatpost, my order of preference would be:
1) vise method (as per Nob). Be careful not to bend the frame, though. You could also put an old saddle on the post, wedge a long metal bar through the saddle rails and use that as a lever.
2) Cut out post with hacksaw blade.
3) Dissolve with caustic soda.

I've done all 3 successfully with different stuck parts. None of them are fun, but the first two at least don't involve risking chemical burns...

Johnny

 

[Robbied196]

Re:

If its definitely stuck the best way is a hacksaw. You lose the seat post but there will be no paint damage and no possible heat issues.

http://forum.ctc.org.uk/viewtopic.php?f=5&t=63229

:roll: Here's one I wrote earlier

 

[Dale cannon]

I cut mine off flush and capped it off with expanded foam. Turned it upside down and poured a strong caustic soda mix in through the BB. I was gone within an hour.

Do it outside and wear scruffy clothes. As the above post said, it goes everywhere.

Have an old pair of gloves handy as well, the bottle gets very hot!

 

[94chas]

Re:

Slit it with a hacksaw blade then collapse it wouldn,t go near it with heat.

 

[deanhempshall]

Re:

Have you tried lots of penetrative oil and brute force? It worked when I got the Gios, soaked over night and got someone to hold the bike while I twisted in an old seat. I did almost break my face when it finally went, but it came free.