DBA Forum (B) - David Beaumont
2014-07-14 20:59:02 UTC
I am considering fixing new aluminium anodes with stainless A4 nuts instead of plain steel or electro plated zinc ones. Normally I wouldn't do this as stainless is much more noble than aluminium and plain steel is much closer in nobility to aluminium. Therefore the anodes would likely erode more in the presence of stainless.
However I see MG Duff sell stainless fixing bolts and also I know I would happily fix an aluminium plate above water with stainless screws but never plain steel or brass - steel would rust and both would devour the aluminium. My 60 year old aluminium train windows seem to be happily secured with stainless bolts.
So I'm thinking the stainless will passivate and not erode the aluminium anodes more than plain steel ones. Maybe even less. Opinion on the web seems divided. Anyone have thoughts on this?
Alternative is to epoxy paint the plain steel nuts but I may want the option to easily remove them as my magnesiums are only 15% down in weight and have served me well in fresh water. They do damage the epoxy in salt water though.
David
However I see MG Duff sell stainless fixing bolts and also I know I would happily fix an aluminium plate above water with stainless screws but never plain steel or brass - steel would rust and both would devour the aluminium. My 60 year old aluminium train windows seem to be happily secured with stainless bolts.
So I'm thinking the stainless will passivate and not erode the aluminium anodes more than plain steel ones. Maybe even less. Opinion on the web seems divided. Anyone have thoughts on this?
Alternative is to epoxy paint the plain steel nuts but I may want the option to easily remove them as my magnesiums are only 15% down in weight and have served me well in fresh water. They do damage the epoxy in salt water though.
David