Thread: One for the metalurgists et al please?

20 years ago I asked a similar question when a steel-framed building on Norfolk Island for which I was managing the repairs needed owing to severe rusting (it was at the top of the cliff at Anson Bay).

I was advised by the civil and structural engineers to not use SS bolts as it was better to have the MS bolts rust away than have the building girders rust away.

Maybe that's why Land Rover don't use SS bolts to hold Defender doors onto the body.

Pretty much as Ron said. With stainless any other metal will be sacrificial. Our you can try to electrically insulate the hinges and screws. Corrosion is driven electrically. No conduction, no problem most of the time.

Are you talking about the screws for the brass hinges???

Originally Posted by gavinwibrow

I have a renovation issue which is going to mean installing mild steel? frames (galvanised and powder coated cos I live near the ocean) into existing openings to support cedar/oregon external but protected french doors and triple parliament ideally brass hinges.
I'm concerned about electrolysis between frame and hinges. Can I resolve this by using stainless steel screws, or am I stumped, or????

The steel is sacrificial compared to SS and brass. I would recommend using the same metal for all parts - ie Galvanised steel.

If you need to use brass hinges (decor etc) you need to insulate the hinges from the mild steel/galvanising. Nylon pads and sleeves to do this should be available from a marine chandler, as these are used on alloy masts to insulate stainless fittings. The actual fasteners would be best made of galvanised mild steel, but you could use brass and insulate this from the steel, or stainless steel is not a major problem against mild steel, but should be insulated from the brass.

John

Originally Posted by isuzurover

Are you talking about the screws for the brass hinges???

Yes Ben, the screws through the brass hinges into the mild steel framework ie the screws make the metal to metal connection.
It sounds like from most posts above I should at the very least stay with galv screws - then maybe paint the heads brass to match the existing hinges, handles and security bolts?
EDIT - just read John's post - I think he is on the money

Originally Posted by gavinwibrow

Yes Ben, the screws through the brass hinges into the mild steel framework ie the screws make the metal to metal connection.
It sounds like from most posts above I should at the very least stay with galv screws - then maybe paint the heads brass to match the existing hinges, handles and security bolts?
EDIT - just read John's post - I think he is on the money

Yes. Duralac is probably sufficient for your purpose.

Originally Posted by p38arover

20 years ago I asked a similar question when a steel-framed building on Norfolk Island for which I was managing the repairs needed owing to severe rusting (it was at the top of the cliff at Anson Bay).

RonB, was that on the cable hut for the telecom cable?

The wife and I lived on Norfolk for a while a few years back. Beautiful place.