Centech Laser Thermometer?

[wiljen]

It is either Harbor freight or Northern tool that has one of the Non-contact Laser thermometers made by Cen-tech advertised for $30 and according to the ad it has a range from -4 to 968 F. Anybody used one? Are they worth $30.

[lurch]

Depends on what you want to measure. If it's something relatively non-reflective (high emissivity) then they should be OK. If it's something shiny like molten lead (low emissivity, and what I assume you're after) I doubt they'll work very well.

The IR thermometers (or pyrometers) need a high emissivity surface to work with. I don't have one personally but have used some (not the Centech though) and they all worked fine for measuring surface temps of electronic components, which are relatively high emissivity. Some brands have an adjustment that can be made to measure low emissivity surfaces accurately, but I doubt the Centech will. If it does, you could calibrate it to handle shiny stuff. For measuring a lead melt, one alternative would be to float a piece of dark, dull steel or other metal in the melt and measure the temperature of that. It should be close enough for the task. No, I haven't tried that, but the theory says it should work... Similarly, a spot on the side of the pot just above the melt might provide a "close enough" place to try and measure if the measurement "spot" (what the thing is really looking at) is small enough.

[cajun shooter]

I purchased an electrical automotive kit that contained a IR thermometer. It's for taking engine block readings. I thought what a neat way to check my RCBS PRO MELT for temp ranges. No can do as the lead gives a false reading. Anything that reflects light will not give true readings. I even tried it while frying turkey thinking the stained peanut oil would read, no again. Works when I need a motor reading such as motorcycle, lawnmower or truck.

[wiljen]

Thanks guys, keeps me from wasting $30 I dont have anyway.

[montana_charlie]

Thanks guys, keeps me from wasting $30 I dont have anyway.
They are useful for checking the temperature of a mould while it's setting on a hotplate, but I wouldn't spend $30 for only that capability.

I have regular use for a multimeter, and finally decided I could live with a digital one. So, I chose a unit that covers all of the normal things (ohms, volts, current, etc.) but also includes an IR thermometer and a K-Type thermocouple capability.

Now, the only temperature I can't accurately measure is my wife's Spanish temper.

CM

[454PB]

The reflectivity can be overcome as lurch mentioned. Float a copper penny or a gas check on the surface and use it as a target. The heat darkens the penny or GC almost immediately and stops reflection.

[RollerCam]

Make sure the penny is 1982 or earlier: melt temp, 1383 deg. F

1983 and later are copper coated zinc, melt temp of 787 deg. F.:x

[jack19512]

Anybody used one? Are they worth $30.







I have the one you are asking about although I have not tried to measure the temp of my melt. I think I will try it and see how it does.