July 13th, 2014

Tempilaq and Green Label Thinner

Tempilaq is a temp-sensitive “paint-on” liquid coating which can be used to gauge case temperatures during the annealing process. Tempilaq is offered in 43 different temperature ratings from 175°F to 1900°F (79°C to 1038°C).

Tempilaq quickly dries, forming a dull, opaque film. Then, when heat is applied to that surface and the rated temperature is reached, the film liquefies, letting you know that you’ve reached the target annealing temp. Because you can ruin brass by over-annealing, we recommend using Tempilaq when annealing, at least when you are setting up your torch position and calculating the amount of time your cases should be exposed to the flame. To prevent premature “burn-off” you can apply the Tempilaq to the inside of the necks.

Thinner for Tempilaq
One of our Forum members from Australia was concerned about some 700° F Tempilaq he had recently obtained. He explained that it was thick and glue-like, making it hard to apply. He wondered if there was a thinner he could use with the 700° Tempilaq.

Yes there is such a product: Green Label Thinner from Tempil (the manufacturer of Tempilaq). Forum member Gary M. (aka gmorganal) tells us: “You can buy Temiplaq thinner from McMaster Carr, and they will have it on your doorstep about the time you hang up the phone. I just ordered from them this week, and [the thinner] was delivered the next day. The thinner is about half the price of the [Tempilaq] paints — roughly $5.00 or so per bottle.” Tempil explains: “Use Green Label Thinner to dilute Tempilaq G® or to replace evaporated solvent. For use only with Tempilaq G® temperature indicating liquid.”