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Infrared Thermometer/Pyrometer?


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Are they viable/affordable, yet?
because I have tried to use a thermocoupler to test and dokument temperatures and those tend to be waay to slow with their readings,
Im looking for something that takes about 1-2 seconds to tell me the temperature of the metal, touch and go style or point and shoot.
so I'm seeing some that are about 30-50 moneybucks and rated for 800+ to 1200+ celsius.
what do I need to know?
how do/dont these work for steel?
are the affordable ones even usable for quick valid readings?
anyone got a cheap one that fits my bill?
 


this is what im looking at, no idea if its good or thrown out money.

https://www.ebay.de/itm/154389108174?epid=6030203708&hash=item23f24ed5ce:g:ug8AAOSw~x9iTAqk

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That sure looks like the one i have but its not the same name. Mines now relegated to a wall ornament. Shoot the walls of the forge and its shows 1900 f shoot the steel it says 1850f. But eyes are saying its welding temp. Right now I'm looking into the.. infurider yf 1500 c.

Saw it last week during my time with a Master bladesmith. Seemed accurate

Just my 2 cents.

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I have yet to find one I trust for what I would call a reasonable amount of money.  Two big things that a lot of people do not realize with IR thermometers is the size of the cone for the reader (close to the gun reads a small area, farther away a bigger area) and emissivity constants (a material dependent value).  When we get to the temperatures we care about in smithing, emissivity constants become important and you will need to calibrate and adjust it for the material.  The cone for the one you linked has a 12:1 ratio, so at 12 inches your diameter being measured is 1 inch.  So unless you can be sure to be measuring just your steel, you will get contaminated readings (measuring the forge wall with the wrong emissivity constant for it).  

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my set up is a japanese style charcoal toolsmith forge,
I dont think I'll ever bother trying to measure the forges heat.
I was thinking of using it as a crutch to learn the temperature of my steel, with different daytime lighting and be somewhat exact with it within 40-60C atleast.

 

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For the reasons Jerrod mentioned, that's not going to be possible with a relatively lower priced IR unit.  An optical pyrometer calibrated for steel would work, but they are not remotely cheap!

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I'm pretty sure, I can measure just the steel, especially for testing purposes I could even use larger steel sheet/plate.
I wont be trying to aim at the steel lying inside my forge, rather pulling it out maybe above the anvil and then, seeing what the gismo says

and it wont be more than 3-5 inches away, if distance is a problem and aiming the thing, it should work out?
and emissivity can be adjusted on most of these(to an extend?)
 

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My experience with the ones that cost less than a few thousand US dollars is that they simply do not work with anything that is emitting visible light.  Much of my real job is in test and measurement.  I've tried these things in hopes of cheap solutions a number of times.  Most recently trying to read the temp of a ceramic part at 1400-1800f.  The values we got with a ~$500 unit were off by 100% or more.

-Brian

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The rule here is that these things simply do not work on things that are hot enough to glow. They just can't read them.  If they did work, we'd all be using them.

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The biggest problem with them is getting an accurate emissivity value. In an industrial process where the surface condition at each point in the process is consistent, the emissivity can be set by measuring the workpiece temperature using a thermocouple (this may mean drilling a hole in a sacrificial sample workpiece and fitting a thermocouple in the hole, pointing the IR pyrometer at the workpiece and adjusting the emissivity until the IR and thermocouple readings are the same.

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For "us", it's not so easy. A workpiece might go into a forge clean and ground with a low emissivity. It'll get hot in the forge. If the forge atmosphere is sufficiently reducing, it might keep the low emissivity. As soon as the workpiece comes out into the air, an Oxide layer will start to form and the emissivity will increase as it does so. 

 

We'll decide the temperature is good and hit the workpiece with a hammer, causing the Oxide layer to detach and the emissivity to drop. The hot workpiece will immediately start to build a fresh Oxide layer and the emissivity will increase again.

 

IR temperature measurement can certainly be useful, but it's probably not for most smiths unless they are able to significantly modify their process to accommodate IR temperature measurement.

 

 

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This has been discussed before. What did y’all not understand last time.

 

it won’t work.

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On 6/23/2022 at 7:45 AM, J.Leon_Szesny said:

I'm pretty sure, I can measure just the steel, especially for testing purposes I could even use larger steel sheet/plate.
I wont be trying to aim at the steel lying inside my forge, rather pulling it out maybe above the anvil and then, seeing what the gismo says

and it wont be more than 3-5 inches away, if distance is a problem and aiming the thing, it should work out?
and emissivity can be adjusted on most of these(to an extend?)
 

Let's say the answer to this question is "yes" or "sort of yes".

What does this do for you? What are you trying to determine the temperature for?

“So I'm lightin' out for the territory, ahead of the scared and the weak and the mean spirited, because Aunt Sally is fixin’ to adopt me and civilize me, and I can't stand it. I've been there before.”

The only bad experience is the one from which you learn nothing.  

 

Josh

http://www.dosgatosdesignsllc.com/#!

https://www.youtube.com/channel/UCdJMFMqnbLYqv965xd64vYg

J.States Bladesmith | Facebook

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I may be way off base here and making an idiot of myself but from what you said I assume you are talking about the "gun" style pyrometer.  If u are talking steel while in the forge for forge welding and etc, I would recommend a type K thermocouple.  They are used a lot in kilns.  They read up to 2400F.  Thru recent experience I found mine was pretty accurate.

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