What sort of rivets?

[jay]

should I use to rivet a stainless spreader root fitting to my aluminium mast?

 

[boatmike]

Ideally Monel.

 

[jay]

Mike- what is monel - and why cant i use stainless rivets?
Jay

 

[sailorman]

[ QUOTE ]
Mike- what is monel - and why cant i use stainless rivets?
Jay

[/ QUOTE ]
try google if u dont belive him

 

[mainmarine]

You also need to insulate the ally mast from the stainless spreader to stop corrosion between the two metals
Malc
Mainmarine

 

[aidancoughlan]

I plugged 100 holes in my mast with rivets recently - Monel rivets as suggested by the rigger. The difference is that (a) Monel rivets wont cause corrosion, and (b) they are more expensive of course.
Insulating the stainless steel from aluminium can be done with Zinc chromate paste, or there is an alternative product available also - a search on old posts for Zinc chromate should find it.

 

[jay]

thanks gents - I'm off to find monel rivets!

 

[john_morris_uk]

A rigger will sell them to you. I bought my last monel rivets from Andy at Allspars, QAB, Plymouth (No connection except he mugs my wallet whenever I go near the place)

 

[William_H]

I am sure you are going to need 3/16 inch Monel pop rivets which take a lot of power to set. You will need something better than the pliars type that are OK for smqaller or Al rivets. You need the lazy tong type which you may have to hire or buy. good luck olewill

 

[ems]

Yep, monel (monometal) is definitely the best. Proctor masts used to use sticky backed plastic as an insulator, so fablon would probably work well. I hope so, because I've just done this on my mast.
Don't forget to plug the rivet heads with abead of silicone to stop ingress of water.

 

[cliff]

[ QUOTE ]
Yep, monel (monometal) is definitely the best.

[/ QUOTE ] Monometal? - Hardly


Monel 400

Carbon 0.3 max
Copper 28 - 34
Iron 2.5 max
Manganese 2 max
Nickel Balance
Silicon 0.5 max
Sulphur 0.024 max


Monel K500 (This is an age-hardenable version of the nickel-copper alloy Monel 400)

Aluminium 2.3 - 3.15
Carbon 0.25 max
Copper 27 - 33
Iron 2 max
Manganese 1.5 max
Nickel Balance
Silicon 0.5 max
Sulphur 0.01 max
Titanium 0.35 - 0.85



Monel R405 (sulphur bearing free machining variety of Monel 400)

Carbon 0.3 max
Copper 28 - 34
Iron 2.5 max
Manganese 2 max
Nickel Balance
Silicon 0.5 max
Sulphur 0.025 - 0.06

Some "Monometal" - Monels are Ni-Cu alloys with additions. In over 30 years in metallurgy I have never come across the term mono metal with reference to monels - is this some new buzz word to confuse us old timers?

When someone mentions monometal to me it conjures up bullets where the bullet is made of solid brass or bronze and not the conventional lead cored, steel shelled, copper washed projectiles (exceptional penetrating power) or the more standard copper jacketed lead cored bullets (medium penetrating power)
----------

 

[msimms]

In a similar vein, what rivets should be used to secure a stainless coupling to stainless rail? I noted the current ones (Aluminium I think) have corroded and need replacing.

Would it be better to use stainless, monel, or stick with the aluminium and replace them every couple of years?

Don't want to change the material and find the rivets stay good and the couplings/rails start to corrode instead!