Technical uses for nail varnish.

I recently mentioned a temperature sensitive nail varnish that could be used to detect hot components. This video is about that varnish and other ones that are useful for technical tasks. Here's a starter search on eBay for the colour changing gels. The most vivid red/yellow one will have a number like 5718. They sell them in multi-colour packs or as single colour bottles for a few dollars. You may find it useful to buy a small UV nail curing lamp too.
https://www.ebay.com/sch/i.html?_from=R40&_sacat=0&LH_BIN=1&_nkw=fairyglo+color+changing&LH_PrefLoc=2&_sop=15
If you want to buy glow in the dark pigment then the keywords are Strontium Aluminate. Quite expensive for the proper stuff, but a little goes a long way.
https://www.ebay.com/sch/i.html?_from=R40&_sacat=0&LH_BIN=1&_nkw=strontium+aluminate&_sop=15
Choose the green/yellow or green/blue colour for highest intensity.
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