Marking various nuts on aircraft engines??

[supercub43]

What kind of paint is used to mark various nuts on aircraft engines to check for unwanted rotation after assembly? It seems to be a thicker then normal paint, but I haven't been able to find any info. Thanks
Brian

[Kyle Boatright]

It is marketed under the name of "Torque Seal"...

https://www.aircraftspruce.com/pages/ep/seals/crosschecktorqueseal.php

[martymayes]

Or you can go directly to the source: http://crosschecknow.com/

On aircraft, it's not limited to engines. Used from spinner to tail. Also not limited to identifying relative movement. Often used during assembly after torquing a fastener so subsequent inspections can use that marking to verify the fastener has been torqued to finish value.

[DaleB]

Torque-Seal is great stuff because it's thick and brittle. I've also seen suggestions to leave the cap off a bottle of nail polish until it thickens up a little.

[supercub43]

It is marketed under the name of "Torque Seal"...

https://www.aircraftspruce.com/pages/ep/seals/crosschecktorqueseal.php
Thanks for the link
Brian