# Question for mechanics **URL:** \ **Category:** Factual Questions\ **Created:** [March 13, 2017, 5:49am UTC](https://boards.straightdope.com/t/question-for-mechanics/782066 "2017-03-13T05:49:13Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Son\_of\_a\_Rich](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/son_of_a_rich/32/5439_2.png) [@Son\_of\_a\_Rich](https://boards.straightdope.com/u/Son_of_a_Rich)\ **Post date:** [March 13, 2017, 5:49am UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/1 "2017-03-13T05:49:13Z")
What do you call that ink that’s applied to fasteners such that it’s apparent if they don’t stay tightened? Thanks! ---
**Author:** ![Weisshund](https://avatars.discourse-cdn.com/v4/letter/w/ba8739/32.png) [@Weisshund](https://boards.straightdope.com/u/Weisshund)\ **Post date:** [March 13, 2017, 6:32am UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/2 "2017-03-13T06:32:41Z")
It’s usually just paint, or sometimes thread lock ---
**Author:** ![48Willys](https://avatars.discourse-cdn.com/v4/letter/4/db5fbb/32.png) [@48Willys](https://boards.straightdope.com/u/48Willys)\ **Post date:** [March 13, 2017, 7:03am UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/3 "2017-03-13T07:03:04Z")
I have heard it called witness paint. Some folks call it torque striping, others call it torque seal. We use it on aircraft a lot. It is thicker than most paints. The stuff we used at the FBOs that I worked at had the consistency of tooth paste, but hardened up to be more like fired clay, just not as brittle. ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [March 13, 2017, 10:12am UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/4 "2017-03-13T10:12:35Z")
Sometimes it’s called “Nail Polish”. Note: you need an old-fashioned nail polish with strong color if you are going to use it for this purpose. Some modern nail polish has too much lacquer and not enough color. An advantage of nail polish is that it quickly dries hard. In contrast, paint cures, and may take all day to do so, reaching full streangth after about a week. ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [March 13, 2017, 3:32pm UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/5 "2017-03-13T15:32:12Z")
Some automotive racing sanctioning bodies mandate these marks on the bolt-nut assemblies of drivetrain components to show the pit crews were not adjusting/tampering with the car while the race was underway during a pit stop. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [March 13, 2017, 3:37pm UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/6 "2017-03-13T15:37:33Z")
Old timey analog electronics had pots that a technician would adjust … then put a glob of that stuff on the pot so we would know if the customer tried to tinker with it … “Sorry, no warranty, you broke it yourself” ---
**Author:** ![Common\_Tater](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/common_tater/32/13846_2.png) [@Common\_Tater](https://boards.straightdope.com/u/Common_Tater)\ **Post date:** [March 13, 2017, 3:58pm UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/7 "2017-03-13T15:58:04Z")
Torque Seal, technically it’s labeled “Anti-Sabotage Lacquer”. ---
**Author:** ![Son\_of\_a\_Rich](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/son_of_a_rich/32/5439_2.png) [@Son\_of\_a\_Rich](https://boards.straightdope.com/u/Son_of_a_Rich)\ **Post date:** [March 13, 2017, 6:13pm UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/8 "2017-03-13T18:13:20Z")
Thanks for the answers! ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [March 13, 2017, 6:46pm UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/9 "2017-03-13T18:46:33Z")
I’ve heard glyptol or glyptal used for this stuff. ---
**Author:** ![Dorjan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dorjan/32/12440_2.png) [@Dorjan](https://boards.straightdope.com/u/Dorjan)\ **Post date:** [March 13, 2017, 8:12pm UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/10 "2017-03-13T20:12:58Z")
On my race bike, I just used white-out. ---
**Author:** ![ZurBob](https://avatars.discourse-cdn.com/v4/letter/z/71e660/32.png) [@ZurBob](https://boards.straightdope.com/u/ZurBob)\ **Post date:** [March 25, 2017, 3:11am UTC](https://boards.straightdope.com/t/question-for-mechanics/782066/11 "2017-03-25T03:11:38Z")
> [@Son\_of\_a\_Rich](#): > > What do you call that ink that’s applied to fasteners such that it’s apparent if they don’t stay tightened? Thanks! Or, _intentionally_ loosened:eek:… Along the lines of 48Willys: We call it “tell-tale” paint.