Pyrometer with Dip probe.

Casting | | | | |

I'm new to this so please be patient with me. I hope to cast Aluminium and Bronze.
I'm looking for a guide on how to build a 'pyrometer' with a 'Dip probe'. I've found a list of bits I think I'll
need off 'ebay'. Are there any guides or plans out there. I've got a tight budget, dont really want to buy one of the shelf.

Also if I can do the above how do I calibrate it?

Here are the parts I've sourced.

High Temperature Thermocouple K type Probe Sensors Item number: 250824170050
Digital LCD Thermometer Temp Meter (K Thermocouple)Item number: 250854622377

High Temp Thermocouple K Type Probe with Terminal Head Item number: 250971853251
NEW MARLIN THERMOCOUPLE PROBE 11-1/2" LENGTH Item number: 200524421772

Any help very much appreciated.


visitor's picture

Pyrometer

I have had one for years but seldom use it. When I do it is to double check real temps as opposed to what I think may be needed.
You will quickly learn to know the proper temps from looks, swishing with a small metal rod for viscosity touch, and just visual and color viewed experience to say nothing of the glow on your face and intuition. Sounds less than accurate I suppose but after years of doing it , it just works.
Each metal and alloy is different anyhow... Don't fret if you can not make or find one. bpfink


Moleburr's picture

Many thanks to you all.

Many thanks to you all.


Rich Waugh's picture

My only experience with

My only experience with using a pyrometer in molten metal was not a good one, so I never repeated it. I stuck my type K thermocouple into a crucible of molten bronze and when I pulled it out there was bronze frozen to it and it was not easy to get off. After that, I just did it like Bruce suggests and judged when it seemed ready to pour and devil take the details. I never had a problem that way, either.

I now have an optical pyrometer that will read to 3000°F, and I don't use it for that, either. Too much trouble to get it out and use it when I can see that the metal is or isn't ready to pour.


visitor's picture

Pyrometer experiences

I tend to use one just to make sure what I think the temp is,, is. Any steel/metal that is going to go int the melt is ALWAYS coated with carbon (acetylene flame - no O2) to keep any bronze from sticking to it (and if some does, it is easy to remove). Any skimmers, stirring rods, pyrometers etc. all are coated with carbon BEFORE immersion. We watch our metal temps pretty close as we do heavy and delicate castings and a couple of hundred degrees one way or the other can have huge effects on what does or does not get filled. We got a GREAT deal on our pyrometer, a gift from Cynthia's passed metal arts teacher from his widow. Had one previously but was very old and poorly stored/handled and was not always accurate. Biggest problem we have is the bronze is "active" on the metal on the tip of the immersion rods and we do have to buy new tip units every year or 2 (we get a few at a time, cheaper, and change them for alloy changes or when the get to looking like 2 pieces of wire twisted together).