stuck stem... Ammonia??

[ScottishRetro]

Well just got a old Steve Goff frame that has a stuck stem.. Par for the course really, me having to sort out other peoples lack of care....

Am I right in thinking ammonia is the solution that will help seperate the metals.. Likly hood of this working??? anyone actually used this method??

 

[1duck]

aluminium seat post + steel frame = use ammonia or caustic soda solution.


I've just done a steel mountain bike frame/aluminium post with the caustic soda, it does work...but its not fast...took me about 10 days to get the whole seat post out.

It really eats the aluminium away so don't expect to be left with a seatpost at the end of it and obviously don't do it where you have an aluminium frame.


After my experience of it i can say it does work, but if you can shift the seatpost in any other way then do that instead.

 

[Broady]

Ammonia eats Aluminium Oxide so providing you can get some in there it should help.

You tried Plusgas? Helped me with a stiff stem once.

 

[Broady]

Oh and if you want to dissolve iron oxide, use white distilled vinegar.

 

[Johnsqual]

Hey,

For me, caustic soda worked a treat on an alu bottom bracket cup
stuck in a steel frame. Great fun as well, fizz fizz, bubble bubble, felt
like an alchemist...

However, two negative points.

First, it left a really nasty sharp edge on what was left of the BB cup, on which I cut myself, so be careful.

Second, either the heat of the reaction or the solution melted some of the paintwork away. I tried to seal it off but the solution leaked out. I read somewhere that caustic
soda doesn't harm paint but as far as I'm concerned that's b0ll0cks.

Best of luck,

Johnny

 

[ScottishRetro]

Ive gone the caustic soda route!!! The stem has been pushed down as far as it will go by the previous owner so the only way to get the fork out was to cut the stem at the top of the headset cup and unscrew :roll:

Really pi$$ed me off as I wanted to get the frame and forks off to the blaster today but it isnt worth the journey unless I can get both the frame and forks to him at the same time, so im now stuck waiting for the soda to do it's stuff :facepalm: ......

Thanks for the info