Copper grease with stainless steel and aluminium?

JumbleDuck

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How relevant is motorcycle engineering though? How often would you fit an anode to a bike to stop it rotting?

One of the reasons for switching to negative earth was cathodic protection. I'm not convinced, but I did think of fitting anodes in the rear wheel arches of my classic cars. Now that I only ever use them in summer the urgency has gone, though.
 

lw395

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It's not correct to be smearing copper grease on hinges, bonnet catches etc. This is what I'm seeing.

A bit like people who service outboards seem to spray white grease 'near' all the fasteners?
It shows they done something for your moeny.
 

pagoda

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And they are absolutely correct in doing so .... although it has taken the motor trade 50 years to catch up with DIY engineers like me. See post #10. ;)

Richard

I have spent countless hours struggling with fasteners which appear to have never had any lubrication from assembly. Some have both old loctite and corrosion! Many have clearly been assembled on the assumption that they will never be disturbed and will never be outside!
My general principle on road vehicles is that I apply a little copper coat to ANY steel threaded parts I have dismanlted- just in case I need to go in there again. I use white water resistant marine grease on the boat externally but would consider a wipe of copper coat on engine mounting bolts as the loads are considerable - and getting these free again is a major pain...
If you have high enough loads- then the copper will limit the possible galling....
 

gus

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The best for marine metal fittings I have found is Lanolin which you can get from the chemists. It doesn't dry up and lasts for years. If you are lucky like I was, you may even pick up a tub that is past its sell/use by date and get it quite cheaply.
On the same vein, use electrical grease for all bulb/contact connections and they then never corrode.
 
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All the OP needs is a good water proof grease. Lewmar Winch Grease.
I accept you have recommended what we should use (stainless / aluminium), but I carry Molybdenum Disulphate grease on board because it is so good at stopping galling with stainless / stainless nuts and bolts etc. How would that work with stainless / aluminium ?
Thanks George
 

penberth3

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I accept you have recommended what we should use (stainless / aluminium), but I carry Molybdenum Disulphate grease on board because it is so good at stopping galling with stainless / stainless nuts and bolts etc. How would that work with stainless / aluminium ?
Thanks George

Should be good. Theory is the Moly flakes form a burnished layer which is what you want for a sliding contact. BTW, I'm sure it's sulphide
 

TSB240

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Recommendation sought for suitable anti seize material for a typical rudder shaft to tiller mounting.
This type of mounting is common to most Jeffa tiller operated rudders.

The various metals are:
Aluminium rudder shaft with through hole for main tiller hinge bolt.
Bronze clamp stock head with through hole for hinge bolt and M8 stainlees cap headed clamp bolt recessed into bronze clamp head (female thread in bronze)
Stainless steel tiller U section for tiller attachment.
M10 Stainless steel through bolt for hinge.

There is also a secondary aluminium clamp ring with a recessed M8 Stainless cap head clamping bolt to prevent rudder dropping out of bushes or bearings.

In my case I carefully reassembled the head assembly coating all fasteners and threads previously using waterproof grease only 3 years ago.

I had done this as all three bolts had to be drilled out due to the previous 15 years of corrosion.

3 years later

I find the main hinge bolt was badly seized into the aluminium rudder shaft but not the bronze clamp head. I eventually removed it by punching it out after repeated applications of heat and penetrating fluid.
Copious quantities of white aluminium oxide was still attached to the plain shank of the bolt.

I understand that I could try using copper grease as an alternative but am concerned about the copper actually promoting the corrosive action and making matters worse.

The two smaller M8 clamp bolts both came undone with very little effort and had no sign of corrosion from reaction with either bronze or aluminium suggesting the waterproof grease had worked for single differential materials.

Any thoughts welcome.
 

Bilgediver

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copper grease should never be used on Ali as the reaction between the two will leave holes (I own an Ali boat), the white deposits could be corrosion or salt, I have used a light oil in the past but i found regular cleaning with boiling water works best.

And if water does not work add some bits of Calgon tablets to water and and dip the ends in this. This mixture also works on Life jacket zips such as the metal ones on some jackets which have become stuck. Just apply it using a wad of wetted tissue.
 

goeasy123

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The purpose of the copper particles in the grease is to provide a bearing surface in situations where mating surfaces are under high static loads. The copper content would not serve any purpose in the OP's application. thinwater is right 'cept it is useful in less that high temperature application.

Try a corrosion inhibiting lube. Corrosion X seems to work well. I have the same problem on the end of my Selden pole. (Umm, sounds like a euphemism!!)
 

Iliade

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Molybdenum Disulphide would be better for most threaded components, but would make a heck of a mess on your sails. It can also be used to actively protect against galvanic corrosion.

However, I would look at silicon or teflon based lubricants for the pole end after first establishing what is going on there. It sounds like the end is eating the pole or suchlike. I'd consider stripping it (i.e. drill out the rivets) and then use assembly paste on reassembly.
 

TernVI

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Recommendation sought for suitable anti seize material for a typical rudder shaft to tiller mounting.
This type of mounting is common to most Jeffa tiller operated rudders.

The various metals are:
Aluminium rudder shaft with through hole for main tiller hinge bolt.
Bronze clamp stock head with through hole for hinge bolt and M8 stainlees cap headed clamp bolt recessed into bronze clamp head (female thread in bronze)
Stainless steel tiller U section for tiller attachment.
M10 Stainless steel through bolt for hinge.

There is also a secondary aluminium clamp ring with a recessed M8 Stainless cap head clamping bolt to prevent rudder dropping out of bushes or bearings.

In my case I carefully reassembled the head assembly coating all fasteners and threads previously using waterproof grease only 3 years ago.

I had done this as all three bolts had to be drilled out due to the previous 15 years of corrosion.

3 years later

I find the main hinge bolt was badly seized into the aluminium rudder shaft but not the bronze clamp head. I eventually removed it by punching it out after repeated applications of heat and penetrating fluid.
Copious quantities of white aluminium oxide was still attached to the plain shank of the bolt.

I understand that I could try using copper grease as an alternative but am concerned about the copper actually promoting the corrosive action and making matters worse.

The two smaller M8 clamp bolts both came undone with very little effort and had no sign of corrosion from reaction with either bronze or aluminium suggesting the waterproof grease had worked for single differential materials.

Any thoughts welcome.
Bronze and aluminium in contact is a nightmare.
It was probably OK when new because the aluminium was anodised, now that's worn off?
I'd be thinking about boring out the bronze bit and isolating it from the ali using a thin plastic bush or shim, but I may not be visualising what you have quite right!
 

geem

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The stainless steel pistons on the ends of my whisker pole fur up and jam with white, crumbly paste. I’ve stripped and cleaned the piston pins, springs and the holes they slide in.

I have some of the insulating paste used to mount stainless steel fittings which will be too thick to use for this - or some copper grease which will work.

The question is - will the copper grease make the corrosion worse or is it safe to use?
Use Tefgel
 

TSB240

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Although copper grease would be better than ordinary grease, I would use aluminium grease for your application.

I'm referring to TSB240 as this is an old thread.

Richard
Thanks Richard.

I will try aluminium grease on the through bolt. I have not checked the Jeffa website for any maintenance recommendations. I am beginning to think removing the tiller assembly and greasing it should be an annual service.
 
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