Caustic soda experts help needed!

[mtbfix]

What concentration to sort a seatpost out and how best applied? Your experience and anecdotes appreciated.

 

[JeRkY]

My seatpost & caustic soda experiemnt failed at any concentration I could make that still poured. Its worth a go but it isnt a magic fix.

 

[mechagouki]

What concentration to sort a seatpost out and how best applied? Your experience and anecdotes appreciated.

if you are talking about a stuck seatpost - try acetone though the BB shell - then (when the acetone has evaporated) heat the whole seat tube up with a blowtorch and throw a bucket of ice-water over it

 

[mtbfix]

I have caustic soda already and no access to a blowtorch. This is really the last ditch attempt as the mechanic put a split on the seat tube a week or two ago.

 

[prof farnsworth]

My seatpost & caustic soda experiemnt failed at any concentration I could make that still poured. Its worth a go but it isnt a magic fix.

did it not react jerky?

when i dropped even a tiny piece of aluminium in the caustic soda soloution i used it created a very violent exothermic reaction. that was quite a low concentration mix.

 

[Andy R]

Maybe you could paint the parts you want to protect with hot wax and then use the cleaner as wax is acid resistant ?

Caustic soda isn't acid, of course.....

I think that I'd paint the solution on with a small paintbrush - wearing good gloves, naturally.

 

[PurpleFrog]

When I was doing my research into powder coating and epoxy paints I found a forum that, weirdly, specializes in this sort thing: www.finishing.com "The home page of the finishing industry". I'd ask there. Removing anodizing from alu was discussed in http://www.finishing.com/2000-2199/2076.shtml.

I also found: http://multietch.com/ - this product is supposed to be good for cleaning ti for anodizing and removing any mistakes in anodizing.

 

[greenstiles]

Does costic soda eat wax then ? if so i stand corrected.

 

[DoctorRad]

My seatpost & caustic soda experiemnt failed at any concentration I could make that still poured. Its worth a go but it isnt a magic fix.

Errr... it was an aluminium seatpost, wasn't it...?

 

[95explosif]

I had the seatpost problem, you can see the thread at:

http://www.retrobike.co.uk/forum/viewtopic.php?t=64637

I used what was a pretty weak concentration and after 5 hours the seatpost was reduced to a thick black liquid.

I would say don't get it near ANY alloy that you want to keep! On top of that, wear a mask, heavy duty gloves and some googles.