F***** Seat Post

[Amanda P]

Ah. But will HCl be any good at dissolving the aluminium oxidey-gungey-corrosioney stuff that is stopping the seat post coming out? Without dissolving too much of the alloy seat post or the steel frame?

It's a fluted seatpost. That's good, I think, because it means I can squirt something corrosive down the flutes to the scene of the action. (But bad because it means salty water was able to run down the flutes to cause the corrosion in the first place...)

 

[just4fun]

taken from a fish keeping forum (which also suggested: You could boil some of your urine to sterilise it and use that! If you are really desperate!)

The bottle i got is made by power MAX, i phoned them up to make sure that it was pure ammonia and explained why i was asking.(to cycle my fish tank)

website: www.challs.com

click on the down arrow under power max and select ammonia.
the other thing you could do is phone them and ask them of a company in your area that they supply.

 

[Amanda P]

Urine is pretty sterile when it.. erm, .. comes out.

In fact int' olden days, they used to wash down the walls of operating theatres with it, because it was sterile. It doesn't, though, contain much ammonia. You'd have to distill it.

Useful link, that, though. Ta. Going to try some Wonder Wheels tonight.

If that fails, I may just pee on it!

 

[J4CKO]

The old DiamondBack has gone back in the shed, for now.....

Needed the space in my garage and I was becoming obsessed, so decided to leave it for a while and then sneak up on it with some new methods.

The missus has just bought a 1967 Fiat 500 so I expect I will be dealing with even more rusty old metal soon.

 

[Amanda P]

Meanwhile, back in my workshop....

Application of Wonder Wheels via small syringe into the flutes has done nothing at all. Worse, I fitted an old saddle (didn't mind if I knackered it).With this firmly attached to said f****** seat post, I fastened in the vice, with the bike upside down on top. The idea was to be able to use the whole bike to increase twisting leverage.

The top part of the micro-adjust thingy cracked apart, so I can no longer attach a saddle.

I don't need to use this bike every day, but it'd be nice if I could! (When it's back on the road, the Flying Banana can go in for powder coating).

Anyway, a bottle of ammonia solution is on order. I'll report further developments.

 

[colly]

Caustic soda will dissolve aluminium oxide. It can be bought as a drain cleaner at most places like B&Q or Homebase.

I have never tried to remove a seat post using it though.

BE WARNED.

It is NASTY stuff. definitely wear gloves and definitely wear goggles, and when you mix it with cold water beware of the fumes it gives off and the fact that the water will get very hot due to chemical reaction.

Other than that it's as safe as houses.

 

[tyred]

Definitely be careful with caustic soda. My hand still bears the scar where I got some splashed on it in the chemistry lab at school.

 

[Amanda P]

Ammonia had arrived last night.

I squirted a few CCs from a syringe down the flutes in the seat post and went and had dinner.

An hour later, I fixed the head of the seat post in the vice, with the rest of the bike standing upside down on top. Using the whole frame as a lever, I heaved the bike round, and...












... it moved! The seat post, rather reluctantly, it's true, rotated in the frame.

There was no way it was going to actually come out, so I squirted in another few CCs and left it soaking. Hopefully, by tonight it will be loose enough to come out.

Watch this space.

 

[just4fun]

its quite pathetic, but i admit, im excited to hear the result

 

[02GF74]

.... and so came back in the morning to see a pool of rank smelling liquid ....

 

[cheadle hulme]

C'mon Uncle Phil, spill the beans. I've got an alu one stuck in a steel frame at the moment. I'm reluctant to pour caustic soda on it if it doesn't work...

 

[Amanda P]

Sorry, chaps, you'll have to bear with me.

I've been away for a long weekend. I can report that the rest of the bike has not dissolved (it was definitely there when I went by) but I won't have a chance to see what further progress with extracting the seatpost can be made until this evening.

I do feel confident enough to be thinking of ordering a new seatpost though.

I still have the other 498 ml of ammonia solution. Perhaps we could have an ammonia relay, like the jersey relay, only we'll just pass it between members with jammed seatposts?

 

[02GF74]

did you say where you purchased the ammonia from?

 

[Amanda P]

dubhghall kindly put in a link to a Fleabay supplier, which is where I got it from.

 

[Amanda P]

But should you need any, I'm happy to send the bottle your way once I've finished with it, which looks likely to be soon. As I say, there are 498 ml left. More or less.