Tool question: Minolta/Land Cyclops 155

[tryppyr]

On my way to visiting the family in MS, I stopped at a junk store in TX and happened upon a Minolta/Land Cyclops model 155 infrared measurement device in the original carrying case and in apparently excellent condition. I checked online for a manual, and only found a manual for the model 152, which seems in most ways to be the same.

It goes without saying I know next to nothing about this device, but for the price I simply could not pass it up.

The model 152 is said to operate between 500 degrees and 3600 degrees. The model 155 I bought has three measuring modes... Peak, Continuous and Average. It also allows you to set the emissivity between 00 and 99, where 00 = 1.00.

It uses a single 9V battery, and when I put one in and turned it on and point the lens at something and press the trigger a U displays at the bottom.

So now the questions.

1) Does anyone know how I might find a manual for this model?
2) Does anyone know what the U stands for? My uneducated guess is "Under operating temperatures"
3) Is this something that would be useful in knifemaking for reading the temperature of forges and heat treat ovens?

Thanks,

- Greg

 

[timgunn1962]

1/ No, sorry.
2/ No, sorry.
3/ It is much less useful than you might think.

IR thermometry is entirely dependent on the emissivity setting for accuracy. For many industrial applications, a temperature measurement is taken with something else whilst the IR reading is taken and the emissivity value is adjusted until both readings match. With a known emissivity value, repeat readings are no problem, so long as the conditions remain consistent. IR can be good for measuring temperatures in ovens and similar: Ovens and deep holes have an emissivity very close to 1.00. It is not necessarily so good for measuring the temperature of gas forges. I have never been able to get "good" temperature measurement with IR in a forge used for HT, finding it much better to use a thermocouple.

IR is great in production situations where there is consistency. In non-production knife-making, things tend not to be so consistent. As metals are heated, Oxide layers tend to form on the surface, changing the emissivity. When forging, the Oxide layer (scale) tends to detach.

The net result is that the knifemaker needs to have the skill to judge when the IR measurement is valid and when it is not. Having that degree of skill and understanding of the process usually means there is no need to use the IR pyrometer.

I gave a cheap import 0-1600 degC (0-2912 degF) IR pyrometer to a smith here in the UK a couple of years ago. He makes Damascus kitchen knives. As I understand it, he used it to check the temperature of billets as they were taken out of the forge and before they went under the power hammer: basically a check on his visual assessment (we tend to go on about the weather a lot over here and lighting conditions vary with the weather). When the IR pyrometer failed, he replaced it, so obviously felt it was worth spending the $200-250 on a new one. He has since moved shop (IIRC, the old one was largely glass-fronted) and this may have reduced/eliminated the need for the IR check.

 

[tryppyr]

Thanks. I appreciate the insights.