stainless stuck in aluminium

[Bosun Higgs]

I know that heat is the answer but had anyone got an idea of how hot I need to get the ally to free off the stainless tube thats stuck in it. I ask because its my anchor roller and there are plastic rollers very close by with a MP of about 160.

My guess is that Im going to have to sacrifice the rollers.

 

[VicS]

I know that heat is the answer but had anyone got an idea of how hot I need to get the ally to free off the stainless tube thats stuck in it. I ask because its my anchor roller and there are plastic rollers very close by with a MP of about 160.

My guess is that Im going to have to sacrifice the rollers.

Try boiling water to start with.

Hot oil ?? Too messy if the fitting is still on the boat.

Can you cut through the stainless steel, remove the rollers, then heat the thing until you can get the remaining bits out... Drill them out ??
Depends which is easier/cheaper to replace. St st tube or plastic rollers.

After 30+ years with a mooring chain over it my roller could do with being replaced anyway!

 

[Ron Dean]

Try boiling water to start with.

I would have thought that would be sufficient.
I remember that the removal of chrome plated gudgeon pins from aluminium alloy pistons, was the common practice of immersing in a bucket of hot water, often below boiling point.

 

[Pye_End]

Might be worth trying a 'cold' spray instead.

 

[Bosun Higgs]

Already had a bo with a hand held blowlamp but the casting is so big ( sadler typre double ally bow roller) that I cant get enough heat into it. Over boiling point but I suspect not by a lot. Next step is SWMBO's oven.

It doesnt help that the muppets who assembled the whole thing used stainless bolts for the spindles of the plastic rollers and screwed them into the ally without duralac or similar. So I not only have a part of the pullpit stuck in the casting but two 10mm bolts as well.

 

[Billjratt]

Is there white stuff visible? If so it can be got rid of with the aquafuerte/spirits of salt type of decalcifier used carefully.
Problem - is the alloy too far gone to survive the treatment - whatever treatment.
As above, sawing out the roller axle may be the cheapest solution as you'll be able to get an ss bolt to replace it.

 

[Neil_Y]

I'd use ACF-50, it dissolves the corossion products and penetrates the corossion. I've used it for seized corroded Al many times.

 

[LONG_KEELER]

I'd use ACF-50, it dissolves the corossion products and penetrates the corossion. I've used it for seized corroded Al many times.

Know the feeling............

I made a bath of diesel and left it for a week. The stuff seems to work it's way anywhere. Lovely.

Did the trick.