My seat post has been in for a few years and seems totally stuck to the steel frame. Is there any magic techniques/ sprays/ lubes that can free it?

Any advise much appreciated!

Elbow grease will free it from the frame!

Consult the oracle Sheldon ‘Unggghhh!’ Brown…

Cut it of about 2 inches from the frame then using a new hacksaw cut 2 slots the length of the insert then you may be able to crush it a bit and get it out

I got one to budge with paraffin (soaking overnight first).
The last solid one I used drills and an expandable reamer

This

Had something very similar recently tried all sorts of nonsense, loads of brute force attacks and a week or so of soakings in various potions and nothing worked until i got hold of some WD40 penetrating spray – proper stuff not standard WD40. Had it free within a couple of hours.

Fun game.

I’ve had successes in the past both at work and home by removing the bb, turning the frame upside down and squirting a fairly strong mix of caustic soda down the seat tube through the hole that should be in the bb shell. You can buy Caustic in Boots (B&Q also sell it);

http://www.boots.com/en/Boots-Caustic-Soda-500g_923900/

Tends to be better for the paint than heat and is much more aggressive in its action than a penetrating fluid.

There’s plenty of warnings about how horrid the stuff is on the bottle…make sure you wash everything down thoroughly after it’s out.

you can try boiling water on the seat tube/stay cluster too, expands the outer tube a wee bit. That’s how I did mine (after soakings with coke etc. 5/10 seconds of boiling water, then foot in the frame by the BB, pull and twist the saddle. 30 odd reps and a couple of blisters later, it was free.

In the end I got mine melted out and had the frame powder coated

Fit a crappy old saddle to it.

Invert bike so it’s upside down, resting on the saddle.

Put a broomstick through the seat rails.

Stand on broomstick, each foot straddling the bike.

Use frame as a lever and twist.

Frame upside down and place the seat clamp in a large vice, spray plus gas into the seat tube bottle bosses or BB area, leave for a few hours/overnight, grab frame and twist side to side and it should free off, if it doesn’t then repeat plus gas and leave a bit longer.

+1 for what somafunk said.

Cutting it and then using a hacksaw is a really long and boring process and I wouldnt recommend it at all.

If not worried about paint too much use caustic soda. Lots of videos on youtube about that. I melted out a seatpost that had been cut off and hammered down a steel frame like this before. But wear protection etc etc and wash off any splashes quickly to avoid paint damage.

Finish Line produce a Release agent called Chill Zone designed for this sort of thing.

Concentrated Nitric Acid will dissolve the frame but your lovely seatpost will be unharmed.
Hope that helps.

Thomson seized in my SIR.9.
Had it soaked in Plusgas for days. 😥
Had cold water pouring into seat post while boiling water on to frame… 😥
Had monkey wrenches of increasing lengths on it… 😥

Be cutting it out I reckon.

I had this on my Genesis Equilibrium. I followed the advice on the Sheldon Brown website in order of increasing destructiveness. I spent 2 weeks riding the bike without the seat clamp done up and soaking with various liquid, ammonia, coke, etc etc.

It didn’t budge. I tried clamping the post and rotating the frame but it didn’t budge. Then Stillsons which just crushed the post.

So I chopped it down and used the long hacksaw method. This is REAL pain staking job and after a morning I got fed up. There was a section that was really welded in.

So I opted for the ‘nuclear’ Caustic Soda solution. My words of advice with this approach are:

1) CARE with the solution. Wear gloves and goggles. If you get this stuff in your eyes IT WILL BLIND YOU.

2) If your skin feels ‘soapy’ you’ve got it on your skin. Wash it off with a weak acid solution e.g. vinegar.

3) Strip the frame down and remove all Aluminium parts.

4) Put the frame upside down. Block what remains of the seatpost with blu-tack, then a plastic bag and tape.

5) Mix up a solution – add the Caustic Soda to the water SLOWLY.

6) I used a syringe and added the solution via the bottle screw holes on the seat tube. Then plugged these up using more blu tac plastic bag and tape.

The frame will get hot and depending on the strength you will hear some hissing and perhaps some volcanic activity of the dissolved alu / caustic soda solution out of the bottom bracket.

When it stops fizzing empty, rinse and repeat.

Once again BE CAREFUL WITH THAT SOLUTION IT WILL BURN YOUR SKIN and BLIND YOU.

Grr can’t seem to embed the video click on this link Krakatoa in a bike frame

There is a chap on line who specialises in such challenges. By all accounts, he’s pretty good. I’ve managed inverting the bike and pouring costic soda in the bottom btacket shell. Disolves the aluminium oxide that has caused the spost to swell and leaves the steel untouched.

Bicarbonate of soda solution is a better washing solution for pretty much anything unless you get to specialised cleaning solutions.

It’s ampoteric and pH8.3 so only just above skin pH.

I wouldn’t use it for strong acids as it can get a bit violent but I would use it after diluting in water.

LOL @ Freesters gameplan! think I’d rather chuck the whole lot in the skip!

Try diesel. Diesel is the most effective penetrating fluid ever, I know cos..
A, I’m an ex motor mechanic, &…
B, I used to have a petrol station & when the seal/gland leaked on the diesel pump nozzle it got sodding everywhere.
Still use it above Plus Gas/WD 40 etc.

Caustic soda is the fun way…

I’ve tried pretty much all the ways:

– In a vice and twisting: Works if the post isn’t too bad
– Caustic soda: Messy and a total PITA.
– Cut off top and use expanding reamer: Slow but works.
– Cut off top and cut slots with hacksaw blade: Slow and a PITA.
– Clamp-on puller widget: Works if not too bad

But now I start with in a vice and twisting – I use a tube block on the post if there’s space to save the head. If that doesn’t work then I move on to cutting slots, but I use a special tool with a depth-guided saw blade.

Finish Line Chill Zone works as above.

Last time I:-

1.Removed saddle
2.Take impressively large blow torch (I’m lucking to have a brazing hearth, but a blow torch should do it) and heat up the exposed seatpost taking care to not point it at the frame and trash the paint.
3.Once it’s good and hot plunge the seatpost into a bucket/dustbin of water to cool it very fast.
4.Repeat five to ten times
5.Then clamp the end of the seatpost in a vice and twist the frame as other have described above.

I’ve just had the same problem and went straight to the caustic soda option. I stripped the frame plugged the holes with plasticine and poured in a very concentrated solution of sodium hydroxide. There was lots of heat, steam and bubbling. After this subsided I emptied it out and repeated. I did this twice a day for a week and the seatpost eventually was dissolved out. The frame is unharmed. I washed out the frame by sticking a hose in the seat tube and let the water run for a couple of ours. I then dried it in the sun and poured in lots of cheap pound shop oil to coat the inside of the tubes. Then re built the bike. Worked a treat and a nice wee project.

Caustic soda for the win

Double post fail

I’ve just removed a aluminium seatpost from a steel road frame using caustic soda. I tried all manor of lubricants, left it with the LBS for a week and tried cutting it out first. I wish I’d saved time and gone straight for the ‘dissolve it out’ method. It took 24hrs with very little effort and no damage to the paint work 🙂 I used 100g to 500ml of water.

Home

Had very similar problem recently with aluminium post and titanium frame. Tried most of the methods above including wd40, freeze spray, plusgas, caustic soda, hacksaw and a vice. In the end I sent it to the seatpost man as suggested on here. 24hrs after arrival it was on its way home with the seat tube like new. Highlly recommended and worth the price.

The last one I did just wouldn’t shift with all known soaking and VERY heavy duty twisting methods. Didn’t fancy caustic so cut off and expanding reamers left the frame unmarked but was slow and sweaty work (it was a thick post so got a good workout).

Have also done one by putting whole frame in -40C cold chamber at work (aluminium contracts more). It worked but have since read up on cold fracture properties of brass and don’t fancy risking it again (fillet brazed frames).

Tried:
Ice down seat post, hot water on seat tube
Drilling hole in seat post, attacking long bar.
Attaching shit seat than twist.
Plus gas.
In the end put the remains of the seat clamp In what remained of the tube. Upside down in big vice twist frame till, ‘bang’ then twist upward, (after plus gas soaking from top and via seat tube bottle cage boss).
So basically what somafunk said.
Edit- need to plug the end of the post with old seat clamp bit otherwise vice will crush not grip.