Taking Temperature Readings

[blackcat26]

Forgive me if this is old news but it's new to me. A guy at work told me that the infrared temp guns won't accurately read shiny surfaces, you need a small pc. of tape on the object measured. Sure enough I tried it on my motor and it reads considerably hotter on the tape than the shiny surface of the water can on my motor.

[m4a1usr]

You sir are 100% correct. There are specific directions to using an infrared temp gun and the most common things you should pay attention to are;

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Do not point at magnetic objects, or those with highly reflective or shiny surfaces.
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Do not point the laser through smoke or glass. The infrared thermometer laser gun will measure the temperature of the smoke or glass instead of objects beyond. This includes sub hatches that some of us tape down to waterproof our hulls. The measurement needs to be taken with the plexiglas/lexan removed to be accurate.
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Avoid using the infrared thermometer next to areas of extreme heat or cold different from that which you measure. For instance, avoid using the temperature gun in a freezer to determine the temperature of an oven.
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Make the measurement as close to the item as possible. There can be resolution issues inherent to each infrared laser gun due to quality of the sensors.

John

[BakedMopar]

Where on the motor do you take your readings from? The can, endbell or the rotor?

[Jedi Master]

I'm glad the question has been asked, and answered. I had no idea. Never fried a motor but will add some tape accordingly to all of my motors! Cheers!!

[AndyKunz]

Hey guys,

I don't want to sound negative or anything, but the temperatures you are reading at the end of a run are nearly useless. We've done a lot with telemetry at work, and after a motor soaks the numbers are extremely misleading. You really need to look at the operating temperature instead, and use that to set up your model.

Don't believe it? Set up a telemetry system on your motor and/or batteries and watch the operating temperatures. Then let it sit for 30 seconds. You won't believe the difference.

Andy

[properchopper]

Hey guys,

I don't want to sound negative or anything, but the temperatures you are reading at the end of a run are nearly useless. We've done a lot with telemetry at work, and after a motor soaks the numbers are extremely misleading. You really need to look at the operating temperature instead, and use that to set up your model.

Don't believe it? Set up a telemetry system on your motor and/or batteries and watch the operating temperatures. Then let it sit for 30 seconds. You won't believe the difference.

Andy

Andy, I've always suspected that what you are saying, happens. During the trip from the shore to the table, and yakking about the run before untaping allows for some substantial cooldown. I usually add some subliminal fudge factor to my readings when analyzing my numbers, & try to keep my setups with that in mind.
Thanks for the input from the empirical side

[forescott]

So what would be a better tool to get more accurate temperature readings?

[Flying Scotsman]

You can use an Eagle Tree micro logger with the appropriate sensors and view the data on a computer, but as Andy mentioned a real time telemetry system is the best as you can view the data as it is happening.

Douggie