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[Marks DTM Calib]

There's an argument going on over on another forum (pikey based !!) where one guy is adamant that copperslip of any sort should NOT be used with alloy wheels .... he's on about "galvanic corrosion"

Apparently copper/aluminium in contact in a salt solution have this reaction, and he says that road salt is sufficient to cause it.

My chemistry is far too old (1965) for me to remember, although I did do "dissimilar metal corrosion" whilst in the RAF,but I think that is different ..  ??

I'll not post any quotes unless requested ....  but do any of the "knowledgeable" folks here have a view on the matter ??

Galvanic corrosion can occur but, it takes around 50 years to start to show and thats if it was bare alloy which it isn't!

What do you expect from a caravan owner 

[Chris_H]

Nice confession! 

Easily done I guess.

Keep an eye on the obituaries column.  It was the wife's Focus!

God there a pain in the arse to do....what with having to remove the whole dam hub

How right you are.  And on one side the backplate came off too - rather a lot to hold onto!  It was only when I did the second side I realised the backplate was supposed to be pop-rivetted to the swing-arm.

[Entwood]

There's an argument going on over on another forum (pikey based !!) where one guy is adamant that copperslip of any sort should NOT be used with alloy wheels .... he's on about "galvanic corrosion"

Apparently copper/aluminium in contact in a salt solution have this reaction, and he says that road salt is sufficient to cause it.

My chemistry is far too old (1965) for me to remember, although I did do "dissimilar metal corrosion" whilst in the RAF,but I think that is different ..  ??

I'll not post any quotes unless requested ....  but do any of the "knowledgeable" folks here have a view on the matter ??

Galvanic corrosion can occur but, it takes around 50 years to start to show and thats if it was bare alloy which it isn't!

What do you expect from a caravan owner 

Thanks Mark ...   I feel a bit of "winding up" coming on ..

[KillerWatt]

Imagine you're replacing some brake shoes and you have two very similar-looking aerosol cans on the ground beside you; one is grease to make the shoes rub nicely on the backplate, the other brake cleaner for preparing the whole shebang for new parts.

You could quite easily get a bit of lube on the new shoes and need to spray them with the brake cleaner couldn't you?

I think it would be a very good idea if the two cans were made really different-looking just in case some imbecile made a mistake.

Just a thought.  No reason for it really....

I agree that you could quite easily pick up the wrong can, but if you don't realise your mistake the minute you pull the trigger then it's highly likely you should be having your brakes serviced by Kwik-Shit

[Chris_H]

Imagine you're replacing some brake shoes and you have two very similar-looking aerosol cans on the ground beside you; one is grease to make the shoes rub nicely on the backplate, the other brake cleaner for preparing the whole shebang for new parts.

You could quite easily get a bit of lube on the new shoes and need to spray them with the brake cleaner couldn't you?

I think it would be a very good idea if the two cans were made really different-looking just in case some imbecile made a mistake.

Just a thought.  No reason for it really....

I agree that you could quite easily pick up the wrong can, but if you don't realise your mistake the minute you pull the trigger then it's highly likely you should be having your brakes serviced by Kwik-Shit

It was considerably quicker than a minute but definitely after a substantial transfer had occurred.

[Tony H]

There's an argument going on over on another forum (pikey based !!) where one guy is adamant that copperslip of any sort should NOT be used with alloy wheels .... he's on about "galvanic corrosion"

Apparently copper/aluminium in contact in a salt solution have this reaction, and he says that road salt is sufficient to cause it.

My chemistry is far too old (1965) for me to remember, although I did do "dissimilar metal corrosion" whilst in the RAF,but I think that is different ..  ??

I'll not post any quotes unless requested ....  but do any of the "knowledgeable" folks here have a view on the matter ??

Galvanic corrosion can occur but, it takes around 50 years to start to show and thats if it was bare alloy which it isn't!

What do you expect from a caravan owner 

Off on a slight tangent galvanic action can be very aggressive in certain circumstances. I heard about a guy who painted the sacrificial anode on his boats outboard motor because it was corroding (numpty ) within 9 months his propellor looked like someone had attacked it with an angle grinder!

[Kevin Wood]

Off on a slight tangent galvanic action can be very aggressive in certain circumstances. I heard about a guy who painted the sacrificial anode on his boats outboard motor because it was corroding (numpty ) within 9 months his propellor looked like someone had attacked it with an angle grinder!

http://en.wikipedia.org/wiki/Galvanic_series

The further apart the metals are on the scale the worse it is. So, copper and Ali not too bad - especially as the copper is in grease so very little potential for electrical contact.

Now consider an oil cooler - stainless steel bolted to an ali cover with a cast iron block bolted to that. Keep that coolant fresh!

Regarding boats you have the added issue of them sitting in seawater which is a much better electrolyte...

Kevin

[Andy B]

Always use copper grease from a tub

But don't tell ChrisGixer. 

Kevin

Pray tell

Just anticipating the next round of the Chrisgixer / AndyB copperslip debate. <reaches for the popcorn> 

Kevin

Ahh... That one

Shove over

Only just seen this thread!!
 
I am right though! 

[TheBoy]

I always put a smear of copperslip on the wheel-hub surface, and this does appear to prevent the wheel sticking to hub.

[Entwood]

This could take a long while ......

It'll get your post count back up mind !!!!

[Vamps]

This could take a long while ......

It'll get your post count back up mind !!!!

And I want this adding to my original....
I have spent hours looking and I can not find a post that would have caused TB to take such action....

[unlucky mark mv6]

Imagine you're replacing some brake shoes and you have two very similar-looking aerosol cans on the ground beside you; one is grease to make the shoes rub nicely on the backplate, the other brake cleaner for preparing the whole shebang for new parts.

You could quite easily get a bit of lube on the new shoes and need to spray them with the brake cleaner couldn't you?

I think it would be a very good idea if the two cans were made really different-looking just in case some imbecile made a mistake.

Just a thought.  No reason for it really....

Yeah,such as me.

[kev2b4]

on a similar vein - i had a beetle clutch plate in gearbox oil - new oil seal , then boil up clutch plate in caustic - dry - then test going up a hill with 4 people in car- lasted for 4 years .