A curiosity/safety question:

I know that if steel & aluminium are left in contact with each other for some length of time the aluminium corrodes and turns to powder (look at old Land Rovers repaired with aluminium plates and steel rivets).

My SRT gear is often stored for weeks at a time between uses with the different metals up against each other. I do clean and dry it before putting it away, so is there much (or any) chance of this corrosion taking place? Should I keep the different metals seperate when not in use?

I've never seen this effect of caving gear, I think because most caving gear is an alloy, rather than pure aluminium.

I have, however, seen some alarming "fur" on various items where they have been stored damp with peaty water on them.  I found a  krab in france once, attached to an petzl ascender that had been there a long time. The krab has "exploded" and delaminated, but the ascnder was perfect, so the exact material seems important.

To be safe, clean and dry everything, and keep aluminium alloy items away from other metals. Aluminium is a very reactive metal in certain circumstances so do not give it an opportunity to demonstrate its properties to you. Kept properly, there shouldn't be a problem. This has been discussed before somewhere here.

There is a lovley delaminated krab hanging off the belfry bar, not sure where it came from but i think it was local (PGS?) nasty.

come look see some time, if your brave enough :tease:

Washed and dried should not be a problem, only seen this this on climbing gear used on sea cliffs where the salt accelerates any potential effects. Remember to open the gates on any maillons so the inside of the screw thread can dry as well...
Incidentally, Land Rover panels are made of an aluminium alloy (birmabright?) as pure aluminium makes for a very poor engineering material, being far too soft and reactive

discussed at length here

http://ukcaving.com/board/index.php/topic,797.0.html

as far as I've seen - it nearly always happens to insitue gear.

Aluminium based alloy Krab + stell hanger + acidic water = mega quick corrosion.

especially if there is some movement - eg falling water on a pitch hitting the krab - this means that any layers of oxide get worn through keeping the 'fresh' metals exposed.

I encountered something similar on my Rack- been in my 'less used' box of stuff in the shed, with the rusty buckle of an old belt sitting on it- a couple of bars on the rack and the krab they were next to got all crispy and 'layers' were coming off the surface.

I used the krab to hang my sledge up in the shed and cleaned the rack up with a dremel....

Just don't leave steel and ali in contact for any significant period if they are likely to be damp. Probably just try not to do it at all, but I never had any probs with my climbing gear and steel pegs / pitons that I keep in the house.

There were some interesting responses to this on this thread http://ukcaving.com/board/index.php?action=post;topic=1848.0;num_replies=11

I think Dep's theory seems most plausible, given the situation I found in my box, but obviously I can't say either way.