Copper grease on bottle screws

Copaslip or PBC?

Cannot think of any reason why not. Just the stuff but wipe away any excess or it will make a nasty mess on your sails.
 
Anything will do on chromed bronze.:D
AFAIK it does not gall like stainless steel.
Reckon mine have been done (infrequently) in their 30+ year life with a heavy waterproof (industrial) grease similar to Castrol Heavy.
 
Look into this further as I was always told copper and stainless are a no no....can lead to some sort of failure in the stainless
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They use copper ferules when splicing stainless steel rigging!
 
Depends a little on the purpose of the greasing. If it is to help prevent galling of stainless steel bottle screws then copper grease will help, although not as well as a molybdenum disulphide grease. Neither will harm the stainless steel. If the purpose is to keep water out of the threads then silicone grease is excellent, as is lanolin.
 
No-one should us copper anything with stainless steel. It causes intergranular penetration which encourages stress corrosion which is fatal to loadbearing members. If a rigger is swaging SS wire he should be using Monel ferrules. Copaslip would be OK for bronze or chromed brass fittings.

I use teflon grease on my SS rigging screws, but silicon grease will do the job. We used to use some yellow gloop on SS to prevent galling when I was working in the nuclear industry, but I can't remember what it was.
 
Topcat47 said:
No-one should us copper anything with stainless steel. It causes intergranular penetration which encourages stress corrosion which is fatal to loadbearing members. If a rigger is swaging SS wire he should be using Monel ferrules. .
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I thought Monel was a copper / nickel alloy:so the copper content of monel would still be in contact with the stainless ( it's not a solution of copper in nickel or vice versa, but rather a mixture of phases).

Graham
 
Dairy farmers use a cream for the teats of their girls. It makes excellent hand cream but best of all is that it is not expensive, clean to use and is good for some marine lubrication / keep the water out purposes.



73s de

Johnth
 
Topcat47 said:
No-one should us copper anything with stainless steel. It causes intergranular penetration which encourages stress corrosion which is fatal to loadbearing members. If a rigger is swaging SS wire he should be using Monel ferrules. Copaslip would be OK for bronze or chromed brass fittings.
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Doesn't apply in this application, unless you were thinking of heating the bottle screws to 800C. Embrittlement of stainless steels by copper occurs if the copper is molten and can be a problem in brazing. No problem at all at ambient temperatures. As already said, copper greases are widely used by riggers.
 
Embrittlement of stainless steels by copper occurs if the copper is molten and can be a problem in brazing. No problem at all at ambient temperatures.
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So that also explains why my standing rigging has not failed at the ferules.
 
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