Screenprinting - Truth about Thermal Temp Guns

[billhoodconsulting]

Yesterday, I used a temp gun to reach into my dryer and take a measurement. The actual temperature in the middle of the dryer was 340 degrees, but the temp gun only measured 320. When aimed just one inch from the ink as it near the exit of the dryer the ink read 275. If I had adjusted the temperature of the dryer based on these readings I would scorched the shirt and over cured the ink causing it to crack and wash away in the laundry. Temp guns just don't work!

[billhoodconsulting]

It is also not measuring the temperature of the flame, but the heat directly above the flame mixed with the temperature of the ambient air in the room at the time. Air is not fully transparent in and of itself. The air in this case was a mixture of dust, lint and all the other nice things that we can't really see and don't want to think that we are inhaling when we breath. A little more thought and you will have it.

[billhoodconsulting]

Good observations, Mr. Stains! I would suspect that the answer will come to you with a little thought. Actually, ice is much lower than the freezing point. Most ice measures about 8˚F - not 32˚F. The gun is not measuring the ice cube at all, even though it is aimed directly at it and is actually only about 15-inches away from the ice cube.

[inkstains1]

Oh and that brings this question if it can't read something semi transparent correctly, how can it read ambient air, that is fully transparent?

[billhoodconsulting]

@inkstains1 - Ah, but air is not fully transparent! Think about it!

[inkstains1]

Why would an ice cube be 79 Degrees? Ice is 32 Degrees or less. It's obviously not capable of measuring semi transparent objects. Also if the ambient air was being read it would be several hundred degrees from a flame. not just 20 degrees higher. However, this does show how flaky a ray gun can be, for sure.