Stuck seat post extractor tool

Before I try caustic soda, has anyone tried this?: http://bikesfornoreason.blogspot.co.uk/2015/01/the-seatpost-from-hell-how-to-remove.html

This makes total sense to me, but seems to good to be true. Any thoughts?

Looks good, I wonder how effective it would be on a alu frame. I imagine it could easily crush the frame where the wood hits the frame.
There's quite a long thread on here somewhere and one over on CTC forum (in "technical too good to lose" section) if you don't get anywhere with this technique.

I fear that the threads on the bolt are more likely to tear before the post comes unstuck. I'd like to give it a go but it might work out more expensive than melting it out. Although less messy.

this guy got videos on stuck seat posts for days - enjoys the challenge
https://www.youtube.com/playlist?list=PLxO5aF0sensjXhaFp2-r5gX6uRZweIn-H
-r5gX6uRZweIn-H

Before I try caustic soda,

... should I UTFS?

I reckon so, yes.

Only works on posts with open topss, only works on frames with large cutouts in the B.B. shell, probably only really safe to use on steel frames and even then...

There are other, better methods which use intelligence (and/or chemistry) rather than brute force to overcome the seatpost-seattube bond.

I don't follow you. What do you mean?

I suppose if you're not trying to save the post you cut the top off.

To clarify, this is a steel frame. I've already cut the top of the seat post off. I feel that the gentle force provided by the physics of this method is cleaner than chemicals. I don't know. I just wanted to know if anyone had tried it.

is the seatpost aluminium?
If so i wouldn't use caustic soda, it takes too long.
Use brick and mortar cleaner (available from B&Q). Melted a aluminum BB shell completely out of my steel frame in a day. Frame will need painting after as it dissolves the paint. Caustic took 4 days and did hardly anything.

I've used caustic soda on an old Ribble 653 frame and it certainly works if your mixture is strong enough - only takes a couple of hours. Big issue is the paint work - it's almost unavoidable getting it everywhere. Here are some of my pics:

Just to re-invigorate this thread in the hope that someone can answer the original question:

Before I try caustic soda, has anyone tried this?: http://bikesfornoreason.blogspot.co.uk/2­015/01/the-seatpost-from-hell-how-to-rem­ove.html

I would try anything before melting it out if you want to preserve the paint.

cutting it out with a reciprocating saw is a good way so long as you know when you have gone through the aluminium and don't cut through the frame. I know a bloke who swears by it and can have it out in no time.

this is how you do it:
https://www.youtube.com/watch?v=LJLZ9Ojtr80

and theres using a slide hammer which seems to do the trick

@dogtemple yeah I've seen that video and am quite tempted to give it a go if I can get hold of a reciprocating saw. I have heard mixed opinions about it though, in terms of knowing when to stop. But the frame isn't anything special, and I think I would rather not make a mess of the paintwork.

I reckon with a rec saw and doing a few cuts you'd only need to cut them to about 95% anyway (and not risk the seattube) and with a bit persuasion it would give and come out.

aluminium is pretty soft, it doesn't spark and it sounds different to steel, those things can help you tell when to stop. just go carefully and level with the tube you should be ok.

Reciprocating saw seems like using a 10lb sledgehammer to hang a picture.

Hacksaw blade glued into a slot in a dowel will be much more controllable.

How do you make a slot in dowel?

A reciprocating saw?

And a 10lb sledgehammer?

And some caustic soda.

I once tried fixing a blade to a dowel, used a Dremelled to cut a slot into the dowel and epoxied the blade into position, but found it was really hard to a) apply enough force against the inside of the post to cut well and b) keep the dowel parallel to the inside of the post to cut evenly through it. Being more rigid using a metal rod rather than wooden dowel would help a lot, but the reciprocating saw approach gets my vote..

Thanks for your anecdotal input. I've found the same problem. I even tried a rec saw blade bolted to a wooden handle but you just can't get the pressure at the tip.

@Dogtemple need to add a recipro saw and air hammer to my tool box. Hammer and grips at the end was a great move.

Tip for the recip saw method - assuming it’s a steel frame and an alu post, the use the saw sparingly, and when you feel you’re getting near the frame, stop every few strokes and use a decent magnet to examine the resulting swarf. When you start to see it stick to the magnet, stop.