So, having budged it only a few weeks ago, the damned thing is now stuck solid in my steel frame. Nothing seems to be shifting it. I've tried spraying the interface with GT85, chain lube and the like and leaving it for a bit. I've given the saddle a twist (not too hard).
I've also hammered upwards at the bottom of the locking collar using a bit of wooden curtain pole and a mallet to try to shock the sod free. I have also loosened off the qr collar entirely and ridden the bike around trying to exert pressure every which way with my backside.
All to no avail. The only bright side is that it still works and is at the right height, but obviously this is small consolation.
I know this thread has probably been done before, and in am due a flaming for allowing this to happen. However, if anyone has any helpful tips that would be great. The only other thing I can think of is heating the seat tube with a hair dryer, trying to free it, cooling, reheating etc.
BB out and spray proper penetrating fluid down the seat tube?
What johnnystorm says. Worked for me but only after I'd left ut sat upside down for a couple of days.
Can anyone recommend a brand of penetrating fluid that is good and I could find easily at Halfords or the like?
Plus Gas.
Or diesel
Plus Gas ordered.
Now I'm going to further risk flaming by asking a question that I think is important - if not strictly relevant.
Putting Plus Gas down the seat tube from the BB means it will run over the bottom of the reverb - ie across the bit where the valve is held. IIRC this is held in place by a circlip in a recess - just the sort of thing that penetrating oil would find its way past. Am I in danger of screwing up the post by doing this?
Now I know this is not strictly relevant as I want/need the post out at some point, but I was thinking of maybe trying it around the top of the seat tube first - will this do any good there?
If just like to thank dannyh- this thread provoked me into checking my Reverb. It wasn't seized but was on its way, quick clean up and some copper grease and its grand.
Someone posted the other day, using a CO2 cannister to chill the inside of the post while heating the frame, to try & break the hold. Don't know what's inside a Reverb, but might be an option.
I have a Thomson seized in my SIR.9, & have tried all the usual solutions.
It's had half a can of Plusgas from all angles, to no avail.
If all else fails it's off to that seatpost chap.
but I was thinking of maybe trying it around the top of the seat tube first - will this do any good there?
You don't want to plusgas the seattube - it'll contract and hold the post even tighter.
Heat the tube. Blowtorch is overkill (and painty-kill, possibly weldy-kill too), hairdryer won't work.
Try boiling water from the kettle around the seat-tube/stay cluster. It will expand, maybe enough to let the post move inside it. Dribble it over slowly for 30s, keep it away from the seatpost otherwise that'll expand too. Give it a yank.
Worked for me!
takisawa - try this. I'm not sure if I'd feel good about being this brutal with a reverb, but it might get you there with the Thomson.
- coca cola down the seattube over a weekend
- forcing apart the clamp slot and spraying GT85 (I used the handle of a table knife in an adjutable spanner)
- boiling water round the top of the seattube.
- Once you've got it moving a bit, then comes the mighty heaving:
- left foot in the downtube/seattube junction, heel of the right hand pushing the back of the saddle towards me, left hand on the nose, pulling and twisting. I won about a millimeter of seatpost per quarter turn, then I had to return it to center for another twist n pull.
- apply more boiling water when it starts to get trickier, every 3 or 4 quarter turns
- repeat as necessary.
wear gloves! I lost skin on 2 fingers and have a big blister in the palm of my hand.
You don't want to plusgas the seattube - it'll contract and hold the post even tighter.
Lost me on this? Plusgas will dissolve the bond bewteen alu seatpost and steel frame. Wont contract anything.
Needs plenty of time though. Leave it a few days but keep topping it up.
*** whhoooOO[b]OOO[/b]Oooooooh **** [think klaxon, or air rad siren]
Announcement:
Ignore my comment about plusgas. I thought it was a cooling thing, like Loctite 8040 Freeze & Release. I was wrong.
[i]Now I know this is not strictly relevant as I want/need the post out at some point, but I was thinking of maybe trying it around the top of the seat tube first - will this do any good there? [/i]
Leave it in until you actually need it out, otherwise you could bu99er up either/or now - as opposed to later.
Based on having to cut out a carbon post from a Ti frame once...
Update. I've managed to get slivers of beer can Aluminium between the tube and post around the slot. I can get about 10mm 'in' and saw back and forth to get a few microns further. This at least gives me some hope for using penetrating oil at the top as I know there is somewhere tangible it can get in and start working a molecule at a time!
Any tips on using Plus Gas are welcome (does it strip paint etc). I haven't used it before, so am wary of the stuff.
Tape wrench?
Plusgas hasn't harmed my paintwork. It's a bit like WD40 but oilier.
I have just removed a Raceface post from my steel Genesis frame. Tried everything, plusgas internal & external for a couple of weeks,heat, Coca Cola squirted inside seat tube via BB shell, even freezing with Liquid nitrogen to try to shock the joint. The thing that worked was a can of coke poured in until it ran out of the BB Shell (obviously with bike upside down) and leaving for 3 days. The resultant CRACK! when it finally gave out(seatpost in vice, twisting frame) was like music to my ears. I thought at first the post had given out but once it started moving it came out really easily. Apparently the slight acid in the coke dissolves the Al Oxide or something. Good Luck