Found Dreaming

Still working on this. Kiln is working well, so I need a whole day to do the burnout and melt some Bronze. It keeps storming and the power goes out, plus I put the car in the garage in case we get another tennis ball HAIL storm. Today there was a storm warning for high wind, lightning and softball sized hail. It didn't materialize, at least not here.
I had 2 temp probes in the kiln today. one read about 150 degrees C higher than the other. The hot one is a harbor fright multimeter with a temp probe from China. The other one is a kiln thermometer I've had for a while. I had calibrated it with molten Aluminum, setting it at 1250 F with most of the ally melted and a little bit of unmelted still in the crucible on a slow melt. I have a small Aluminum melt to do, so maybe I'll re-calibrate them with that. I can see where checking Ice water and boiling water would help much with 1250 to 2100 F.

If your thermocouples are not compromised, then one of your meters may be. Also, you have to take into account that the Harbor Freight meter is going to measure the difference between the temperature of the end of the probe (in the kiln) and the temperature of the meter. A multimeter does not measure absolute temperature; whereas a kiln thermometer should have a compensating function built in to take care of that difference.

Richard

Here's a picture of each of the set-ups. The multi-meter has a temperature setting on the dial, so I would think it already compensates for the ambient temp. It's already reading higher than the pyrometer.

The picture of the pyrometer shows 600 C while the meter shows 714 C. I hooked it up to read milli-volts and got 28.6. On the chart, that's around 1269 F plus 65 ambient is 1334 F or 723 C.

I have that exact same analog meter. I haven't used it in years. I bought it from Sundance Glass.

I understand that analog meters tend to be less precise than digital.

I keep records of the temperatures of my burnouts and metal pours, but I record in millivolts rather than degrees. And I always use the same model of Harbor Freight multimeter.

Richard

I does seem to be hotter than the pyrometer shows. I had it at 1550 F and I think I almost melted a piece of Cast Iron that was in the kiln. I was trying to use it as a mold for the glass, but I don't think it worked. I can hardly wait to hook up the PID controller, I'm sure it will have another temp.

I like the Milli-volt idea, anything to cut down on converting temps. I am slipping into Metric mainly for volumes, it's so much simpler.

I know the analog is old, it still says centigrade temp. I got razzed when I went back to college at 1983. I said Centigrade and the teacher started laughing. He said "How old are you?" Then everyone laughed... I still say centigrade sometimes.

Whats wrong with saying centigrade. My pyrometer is similar to a Marshall lance and I think it reads low and I have no way to calibrate it so I just use the temps that it reads as my guide. I did take it to work once and put the probe in a oven that was set to 200c, it was just a few degrees out and I adjusted it, but at higher temps I think its still low. Aluminum pouring tempt for me is 670 deg c

I just noticed on my analog is reading 0 instead of near 75 F. Maybe checking it with boiling water would help.

Whats wrong with saying centigrade.

You can't imagine how political correctness has corrupted the English language in the United States. Euphemisms are the norm. Now it is bad form to call a spade a spade. Centigrade must be too straight forward.
Americans have also changed:

city dumps into sanitary landfills
prisons into correctional facilities (Does anyone imagine there is any correction going on in those places?)
black people into African Americans (if that's the case then please stop calling me a white person, and call me an English American.)
emergency rooms into critical care facilities
medical insurance into health insurance (it's not insuring your health; it's simply paying your bills when you get sick.)
Oh, and my favorite, "She lost her mother." My immediate reaction is to organize a search party to go find her.
Or he passed away. What's wrong with the truth. The man died.

I could go on.

Richard

Well, we are certainly a busy bunch. I've just been tinkering around with little things. Just can't pull the trigger to do the burnout and cast the bronze things I have molded up. I figure I need a full day to burnout the investment, then melt the bronze and pour. We're getting some weather today, most of the bad stuff missed us to the south, David has been getting pounded from what I see on the weather channel.

Come on, go outside and do something!

its been too wet here to do any thing other then watch the tube