Nut/thread securing compound

"Eugene Wendland" wrote in message
...
Does anyone know what compound is used to secure the nuts and threads on
aviation engines? I'm not talking about loctite, but the compound that is
placed on the outside of the nut and then onto the threads. Usually, it's
a
very visible colour and laid in a straight line so that one can visually
see
if a nut or bolt has backed off. I've seen it done with silicon, but I'm
wondering what the real hard compound is. Any suggestions?

Here's one for the "Don't try this at home" file.

Years ago (when Eisenhower was Pres.) I worked in the shipyards as a
pipefitter. I forget why, but occasionally we would seal pipe threads with a
creamy mixture of Litharge and Glycerine. It would harden into a white
substance with excellent sealing properties.

There was a setup table in the shop made from granite. One day a forklift
got too close and busted off a corner of the table. Somebody got the idea to
glue it back on with the Litharge/Glycerine goo. Worked good.

Sometime after I left the trade, I'm told that a fitter was pounding on a
piece of steel which was lying on the broken seam. Now, I won't swear to
this, 'cuz I didn't see it, but it seems the mix had turned into
nitroglycerine and blew up. So, think twice about where you're hammering!
)

Rich S.