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Jock The Rock
11-02-2008, 03:56 PM
hey

i recently bolted a couple of stainless steel handles to my aluminium tinny and i was just wonderin do i need to worry about electrloisis?

ive heard that galvanising and aluminium react but i didnt know about stainless and aluminium

thanks for ur help

TonyM
11-02-2008, 04:00 PM
Yes any dissimilar metal on a tinny can cause electrolysis.

Get a hold of some Duralac and use it on any joins with dissimilar metals and you'll help to minimise the risk of electrolysis (almost impossible to completely stop it)

chewy01
11-02-2008, 04:01 PM
Yea mate it will react. The stuff i used to use on my tinny was duralac i think.you just apply it to the screws and in betweem the st/st and ally. I'm sure there are other products out there.
cheers chewy:)

Jock The Rock
11-02-2008, 04:04 PM
ok thanks would i just get that from a marine shop?

marty+jojo
11-02-2008, 04:07 PM
ok thanks would i just get that from a marine shop?

Yes, duralac is the go any boat/ chandlery shop should have it.

Jock The Rock
11-02-2008, 04:08 PM
ok thanks for ur help

Spaniard_King
11-02-2008, 04:13 PM
You need to insulate the handles from the tinny as well not just the fasteners.

If you can get some thin nylon and put between the handles and the ally and use duralac on the fasteners

Jock The Rock
11-02-2008, 06:40 PM
gaday garry

i dont think i have any thin nylon would inner tube rubber do?

thanks

trueblue
11-02-2008, 08:14 PM
inner tube would do, basically you want a non reactive gasket. Nylon is better for anything that will take significant loads though as inner tube rubber is flexible

Spaniard_King
11-02-2008, 10:42 PM
Jock you could even use something like the plastic from an Ice cream container

fishing111
11-02-2008, 11:18 PM
I don't think rubber tubing would be any good, rubber has carbon in it and that reacts with alluminium.

MTAQ/BTAQ
12-02-2008, 06:10 AM
The idea is not to have any salt water making contact with 2 dissimilar metals because then you set up an electrloytic reaction (similar to a car battery which is 2 dissimilar metals in an acidic solution - pH of seawater is 8 which makes it slightly acid) - solution is to hose all metalic surfaces with freshwater OR a non conductive surface separating the two dissimilar metals OR have two non reactive metals.

So do not leave that lead fishing sinker in the bottom of your aluminium tinnie without a flush with fresh water

TheRealAndy
12-02-2008, 06:51 AM
Jock you could even use something like the plastic from an Ice cream container

Thats what I use on the yacht mast, works a treat.

Its also worth saying that you should pull off all your fittings once a year/2 years and check for corrosion then refit with some fresh duralec.

Crocodile
12-02-2008, 08:57 AM
Be careful if using Duralac, it has some very nasty stuff in it.
Have a quick look on google for duralac and health if you want a good fright.

Jock The Rock
12-02-2008, 03:30 PM
ok thanks for all ur advice it been bloody helpful :)

cod muncher
13-02-2008, 08:11 AM
old mate dont worry , stainless is the closest metal to aluminium so it wont react ,>:(

PWCDad
13-02-2008, 08:48 AM
old mate dont worry , stainless is the closest metal to aluminium so it wont react ,>:(


On the Nobility Scale stainless steel is a cathodic metal (passivated) if "active stainless" it falls about half way between Anodic and Cathodic ... but is still a way away from anodic aluminium.

It will react markedly without protection ...

As stated above ... we are always chasing our tail with corrosion .... but that is half the fun of boats ... fiddling with them !

Unless you have a poly boat ....

Disregard above you were just saying it tongue in cheek ....

Regards
PWCDad

Duyz72
15-02-2008, 08:15 PM
I don't think rubber tubing would be any good, rubber has carbon in it and that reacts with alluminium.

Would be hard not to find something with Carbon in it.
All petrochemical products are carbon based chains.

We are carbon based life forms, not much electolysis happening though (tongue in cheek)