Remove corroded aluminum screws

[jfkal]

Anyone with a trick on how to remove aluminum screws corroded solid in aluminum mast? I tried: Heat, cold, WD40. Not budging :-(

 

[wallacebob]

Impact driver, but that will probably shear screw. WD is not the best anyway, Plusgas or similar.

 

[Boathook]

Years ago I had to drill them out. both parts being aluminium you can't rely upon different expansion rates by heating or freezing the surrounding area.

 

[Boater Sam]

Caustic soda will dissolve aluminium. Judicious use may loosen the screws but protect the mast with grease at least.

 

[vyv_cox]

Hydrochloric acid dissolves the carbonate deposit that results from galvanic corrosion. It also attacks pure aluminium but your mast is made from an alloy that is far more resistant. Even so, take it easy with a few drops of acid at a time and wash copiously with water when complete .

See the article at the bottom of this page Corrosion

 

[Neeves]

Anyone with a trick on how to remove aluminum screws corroded solid in aluminum mast? I tried: Heat, cold, WD40. Not budging :-(

I'm very unobservant but aluminium screws in an aluminium mast seems most unusual.

Jonathan