corrosion

[poter]

Just dismantled the rigging off the mast & found in lots of corrosion between the aluminium & metal screws, when I fix again what can I use that is sure to stop the corrosion?

 

[KevinT1]

Duralac

Duralac - available from your local chandlery around £12 a tube

Be careful where it goes as it is a booger to clean off.

Kevin

 

[Ex-SolentBoy]

This question has been asked many, many times.

The uninformed will come on here and tell you to use Duralac.

Ignore them and use Tefgel.

It doesn't go hard
It's easier to apply
It's easier to clean off
It lasts longer
It works better

 

[VicS]

Duralac, which is barium chromate paste that inhibits corrosion between dissimilar metals
http://www.llewellyn-ryland.co.uk/downloads/duralac.pdf

Or Tefgel which is Teflon based and works by excluding water from the joint.
http://www.tefgel.com/contain.php?param=tefgel_infor#

 

[poter]

thanks chaps!

 

[Seajet]

This question has been asked many, many times.

The uninformed will come on here and tell you to use Duralac.

Ignore them and use Tefgel.

It doesn't go hard
It's easier to apply
It's easier to clean off
It lasts longer
It works better

I'd be interested to know the reasoning behind that somewhat bold statement.

I was trained and qualified as a fighter aircraft fitter / engineer, and zinc chromate paste was considered essential, woe betide anyone not using it !

My Bowman kit mast was put together using the stuff at every item rivetted on, I'm happy to say...no sign of corrosion after 34 years

 

[VicS]

............. zinc chromate paste was considered essential, .............

Any idea when barium chromate replaced zinc chromate and why ?

 

[vyv_cox]

Any idea when barium chromate replaced zinc chromate and why ?

I wondered that when you posted barium earlier. It was always zinc when i used it, but i have not done so for years.

 

[lw395]

If you read the Tefgel blurb, it requires the mating surfaces to match within 10thou, or 10 mil in redneck speak.
Otherwise water can get in there by capillary action.

10 thou is not going to happen for things like a stainless tang riveted onto an ali mast.
Or anything of any size screwed or riveted on.
So I'm afraid the horrible yellow gunge that we know and love as Duralac still has its place in the toolbox.
For a simple screw into alloy, Loctite offers a reasonable level of protection.

 

[Ex-SolentBoy]

I'd be interested to know the reasoning behind that somewhat bold statement.

I was trained and qualified as a fighter aircraft fitter / engineer, and zinc chromate paste was considered essential, woe betide anyone not using it !

My Bowman kit mast was put together using the stuff at every item rivetted on, I'm happy to say...no sign of corrosion after 34 years

I am not saying zinc chromate doesn't work. It was all over my plane and worked well. Being Russian they called it Yak s**t though.

The point is that Tefgel is a modern age product. It is now used extensively in the aviation industry and in sailing.

I have spoken to several professional riggers who now use it instead of Duralac for the reasons I mentioned above.

 

[Nigel_Ward]

Any idea when barium chromate replaced zinc chromate and why ?

I think it may be the Health and Safety risks are less with barium chromate than Zinc chromate (http://www.osha.gov/SLTC/healthguidelines/zincchromate/recognition.html)

 

[VicS]

I think it may be the Health and Safety risks are less with barium chromate than Zinc chromate

That is what I assumed. I think barium chromate is even less soluble than zinc chromate so perhaps that's the reason why.