Question for you Fly-Boys :D

RichardH

AKA The Mad Hat Man
Supporter
Many years ago, when I was working in the aircraft industry there was a fluid called Alacrom???? Which was, I believe a Chromate primer for Aluminium articles which needed to be "fettled" to fit. At the same time I used to use a yellow paste when fitting steel bolts thro Alloy panels. I believe that this was to reduce/stop electrolytic corrosion.
Having spent 9 hours!!! yesterday :( removing a siezed bolt from within an Aluminium Alloy casting (Water pump/Timing cover on a Landrover) because of corrosion, sufficient to shear the bolt twice!! (once with an external stud remover), thought I would look into trying to obtain something to ....
a) Seal against Oxidisation of the machined Alloy housing.
b) Protect against the new bolts corroding into the housing again.

I know that some peeps swear by using loads of Coppaslip or similar but do any of you know where I can get small quantities of Alacrom (or similar) and this yellow anti sieze/corrosion inhibitor paste from?
Preferable (as usual) without spending a mortgage on getting it ;).
 

RichardH

AKA The Mad Hat Man
Supporter
Brill - thanks for quick replies :D

Google came up with this too :eek:
There also seems to be some doubt over its effectiveness/legality - here???
 

RichardH

AKA The Mad Hat Man
Supporter
I seem to have opened up a can of worms here....
having had a look at the Molyslip site (manufacturers of Copaslip) I notice that they manufacture a product called "Aluslip" which seems to be an aluminium based version of Copaslip; but I could find no reference as to when or why you would use one or the other - except for "to be used when copper based products cannot be tolerated"

I also notice that they manufacture a couple (well lots really) of products that would be useful in a hostile (automotive) environment - such as "Rusolvent" - penetrates clearances and cuts through rust and corrosion to free and release corroded parts. Also Molyslip EHT - for those hard to get apart exhaust systems, as even if carbonisation occurs the residue will remain friable.

Have any of you guys tried either of these products?
 

Doug S.

The protoplasm may be 70, but the spirit is 32!
Lifetime Supporter
Having spent 9 hours!!! yesterday :( removing a siezed bolt from within an Aluminium Alloy casting (Water pump/Timing cover on a Landrover) because of corrosion, sufficient to shear the bolt twice!! (once with an external stud remover), thought I would look into trying to obtain something to ....
a) Seal against Oxidisation of the machined Alloy housing.
b) Protect against the new bolts corroding into the housing again.
Maybe a low-tech solution....how about some anti-sieze lubricant? I always use some when I change the spark plugs in my aluminum head Honda and Mazda engines....would that work in your application?

Doug
 

David Morton

Lifetime Supporter
How would a pilot know anything about any of this? It's either serviceable or it's not. If it's actually serviceable it can be made unserviceable quite easily. As for unscrewing parts, thats for the techies. Once they sign the tech log that something is serviceable and shut the door or canopy from the outside, then playtime commences. But - unscrewing things?
"Not my aisle" the cabin crew (plate layers) used to quip.
 

RichardH

AKA The Mad Hat Man
Supporter
Sorry David - I am suitable chastised :(.
I actually meant peeps that work in the aircraft industry - not just the glory-boys ;).
 

RichardH

AKA The Mad Hat Man
Supporter
Maybe a low-tech solution....how about some anti-sieze lubricant? I always use some when I change the spark plugs in my aluminum head Honda and Mazda engines....would that work in your application?

Doug
Exactly - but anti-sieze lubricant is not much good if the aluminium is not protected. The Mastinox is an anti-sieze compound. You will notice I mentioned "Copaslip"
 

Scott Calabro

Supporter
Richard,

If the mastnox is too expensive...I don't blame you!

E mail me @ [email protected] with a shipping address and I'll mail you an expired tube free.

Not technically good for aircraft anymore but the best you will get for what you want it to do.

Regards,
S
 
Last edited:

RichardH

AKA The Mad Hat Man
Supporter
Thanks Scott. A very kind offer, but I am still at the evaluating stage. Is that sorta stuff better than using Copaslip or Aluslip on all mating parts?
 

Scott Calabro

Supporter
If you want to mechanically join two dissimilar metals like steel and aluminum, and prevent galvanic corrosion for all eternity, then Mastinox is what you want.

However, for what you want to do you will be fine with any good anti-seize compound.

Cheers,
S
 
Top