Anti corrosive barrier

Ok, Duralac it is then whenever I replace anything stainless on me ally mast! Thanx for the info.  

Originally posted by Granite Duralac is zinc chromate paste and acts as a sacrificial anode.

Its not! I always though that, but the other day I looked it up and it is in fact Barium Chromate and it seems the chemistry going on is a lot more complicated. I didn't find a source I trusted to work out exactly how it works - especially with carbon - but it definitely says barium chromate on the tube I have.

A2 stainless will survive in the short-term, provided you give it a sloosh down with fresh water on a fairly regular basis. You might start to get a bit of discolouration but that, in the, again, short-term, shouldn't present a problem. Looking at the state of a lot of the fastenings on several SMODs, it is clear that their suppliers are more than happy to use A2 rather than the significantly more expensive A4.

But then again....there are different qualities of A4 stainless out there .

 

Edited by Alistair426

Duralac is zinc chromate paste and acts as a sacrificial anode.
 
With Aluminium and stainless the ali corrodes. With Carbon and pretty much any metal the metal corodes. If  the corrosion products cause the metal to expand then the carbon can get damaged, like putting an ali tube in a carbon mast (Old RS600 masts)

You want to avoid getting it onto your skin as it is quite nasty, it is also a pain to wash out of clothes.

I'd use duralac. By all means use your bit of plastic milk container to smear duralac into the gap though.

And yes, if anything its *more* important to use it on carbon spars than on aluminium.