Stuck seatpost

[BoyBurning]

Re: Re:

Speaking as a philosopher, the post is stuck, therefore the post exists.

Hope that helps a lot.

But, does the frame exist...?

 

[Imlach]

Late start to the day, it's been sizzling away for a couple of hours. Will leave it until the morning I reckon. The CND pattern probably makes everything a bit slower, but I can definitely tell that the aluminium is starting to get thinner, it's looking real manky right now. Have been thinking about approaches, some seem to have rid the seat tube of the post in a matter of a day, others a week or more. It seems that using quite concentrated mix, rather than really diluted, and topping up frequently leads to faster results but also more spillage. My current approach is making a nice strong mix, feeding through the bottom bracket and letting it sit. It goes from steaming and quite warm, slows down a bit and then picks up again - is that normal? I did attempt to give the seatpost a warm hug by the vice in the hope that maybe the caustic soda had loosened the bond, but I've now decided to stick to dissolving.

Input always welcome.

 

[Woz]

Well we are engineers here, not chemists.....

 

[Imlach]

Had to refill again, this time far more concentrated and it seems to be a lot more reactive. Will now leave it to sizzle away through the night while I down some beers. Hoping 1 or 2 more cycles of caustic soda should do the trick. If the seatpost is out before the end of the weekend I'm going to be absolutely chuffed.

 

[k-rod]

Re:

You mean "one or two more cycles of beer", don't you?

 

[Imlach]

Re: Re:

You mean "one or two more cycles of beer", don't you?

Maybe

After 15 beers and a good sleep I woke up and cleaned up the bike. The CND logo is starting to get paper thin, although the walls of the post are still fairly sturdy. But it seems like it's getting closer!

 

[Imlach]

And it's out. Caustic soda is brilliant stuff, next time I encounter a stubborn seatpost I know what I'll be using. Stripped a tiny bit of paint near the top of the seat tube but I reckon I'll respray or get the frame powdercoated at some point in the near future.

 

[charliealphamike]

Get yourself a Strap Wrench. Mine's made by Titan (red handle) but others are available. I bought mine locally but I note you can get them from Amazon (or a good independent tool supplier). You want one with a fabric strap but you might need to use some sandpaper/wet and dry between the Strap and the seat post for some extra grip.

 

[Magpiegifts]

Re: Re:

Hate to tell you, but that's a pretty rare seat post you've cut up.

Almost certainly worth more than the frame.

Out of interest,what seatpost is it?

 

[Imlach]

Re: Re:

Hate to tell you, but that's a pretty rare seat post you've cut up.

Almost certainly worth more than the frame.

Out of interest,what seatpost is it?

It was a kona race light seatpost, the types that came stock on high end Kona. Glad to be rid of the sucker, the amount of rust inside the seat tube made it clear that there's no way that thing would have come out looking even remotely presentable. Will be replaced with a syncros post in the near future. The intention was never to keep that post even if it had come out.