I have a handheld pyrometer; I'm not convinced of its accuracy.  I see digital thermometers with thermocouple probes for sale. What is your experience with them?

I have a temp probe on my multi meter. It of course will not read that high of temps though. As far as it's working it is pretty accurate. The draw back i would see, if the ones you refer to are like mine, is that it is thin metal wire and i would be hesitant to stick that in a place that gets hot enough to melt steel. 

I am not saying that no one makes a probe capable of handling those temps, never needed one so never looked, but over all i have had good results with the probe type temp readings. 

May have to do a bit of experimenting with mine. My multi meter is made for automotive work and i know for a fact it can read up to 500F. Or i could go the easiest route and see if max temp is in the instruction manual but what is the fun in that? 

If I remember right my multimeter temp probe, like you mention Billy, only went up in the 900°f range. I did try it in the forge and as you might guess, it ruined the probe. So I had to buy a new one. 

I believe I've seen them out there to take higher temps but they are too pricy for me to be interested when I would have limited need. 

I took the pyrometer with a thermocouple probe that we used in the ceramic kilns.  It was red lined at 2000° F and when I put into the forge we had built, it red lined in about 5 min. and I didn't get it pulled out before it melted, so I guess it was red lined for a reason. Still haven't replaced it as in the kilns we use different cones that bend over at set temperatures and are as accurate as the pyrometer was.

I can't control the wind, all I can do is adjust my sail’s.
Semper Paratus

 

We've had this conversation a few times with similar results. I judge mine by eye and how the steel feels under the hammer. However for folk who need or heck want to have a better idea of temp. Are there any kiln, cones that reach 2,600f or better?

If they're available I bet they'd be cheaper and easier to find than metal samples with appropriate melting points. 

Frosty The Lucky.

Search on Amazon for "2732 pyrometer" and you will find a number of infra-red digital pyrometers that can measure up to 2732 degrees Fahrenheit, at a good price, and can measure from a good distance away, so that you don't have to get too close to the forge.

I got one a few years ago and it has worked well for tweaking rough heat-treat temps, etc.  For the price, I thought I'd take a chance, and it has worked out well, and doesn't get overloaded at high forge temps.

Hope this helps.

Tink!

Cool, thanks Tink!

A quick search of "Amazon Prime" says they want $59 and change. The demo video made me think the person doing it hadn't handled one before. Forge was the first "use" they listed even.

Tempting and I don't spend much time at the anvil anymore. <sigh> However I'll have to pass word to out club. 

Frosty The Lucky.

That is about as high a temperature as a first class burner in a first class forge is able to reach on propane

19 hours ago, Frosty said:

Are there any kiln, cones that reach 2,600f or better?

The highest cone's we have are cone 10, which slump at 2284-2381°F, the highest cone made is a cone 14 which slump at 2464-2523°F pretty close to 2600.

Haven't needed them as we have also learned to judge like you how the steel feels under the hammer and color. We only used them to see what the new forge would do with the Gaco 750 kiln burner, that y'all helped us while building it. It did fine and melted the cone 10s in about 8 min.

I can't control the wind, all I can do is adjust my sail’s.
Semper Paratus

 

Thanks Randy, saved me a call to a ceramics supply to find out. Tink however rendered my thought moot with the 2731f pyrometer on Amazon. 

I find myself wondering why so many of my ideas are moot now days?

Frosty The Lucky.

Perhaps you're turning into an old coot?

best wishes from the other one

On 8/5/2024 at 1:33 PM, Frosty said:

A quick search of "Amazon Prime" says they want $59 and change

I have one of these, and it does seem helpful, but remember that you are measuring surface temperature of the inside of the forge, not ambient.  This will be close, but certainly not exact (might be an issue for very precise heat treatment).  I have heard feedback that accuracy can be a little questionable based on what material and material color you are scoping.  What little calibration I've done on mine seems to indicate that it is pretty accurate measuring surface temperature of blade stock being heat treated once the steel is outside the forge chamber.

When I used to use a thermocouple inside my glass furnace that ran up to 2,400 deg. F during melting I used a 10 or 12 gauge unit inside a high alumina ceramic well.  This worked pretty well, but degraded over time since type K isn't really rated for those extremes.  Not sure how accurate it was.  As Frosty mentioned earlier, it was good for a reference to match expectations on how the material behaves empirically (kind of like a pressure gauge on the gas line downstream of your regulator).

I suppose that's true Mike, I tend to range between nice old grandpa type to cranky crab old coot. Too bad for the annoying youngsters around us eh?.

Here's to being older and older coots!

Frosty The Lucky.

 

Good Morning,

Older and Older, is that plural or multiple???? LOL

I am not Old or Older. I am the "Ol' Coot"  LOL

Neil

Sorry Latticino, I didn't mean to ignore your post I just get carried away. 

I take your meaning about accuracy and thermocouples, it makes perfect sense. Heck it should be evident given thought, we've discussed blade placement in forges to deal with the issues. 

Not being a bladesmith guy I find myself wondering to what degree accurate temp control is necessary. I understand wanting to know/control exactly but how close does it actually need to be? I get it for glass work and ceramic glazes can be really finnicky. Mokume Gane likes precise temperatures but the sweet temp is usually easily visible, holding it for the soak can be tricky depending on the billet. 

Shooting the temp outside the forge makes perfect sense, it's how we checked samples where precision temps were necessary.

Now I'm in danger of rambling . . . LOTS.

Frosty The Lucky. 

 

Frosty,

No worries.  You shouldn't feel obligated to respond to every post on the forum, even if your name is mentioned.  I know you have a full life outside of this virtual one.

I'm not really sure how accurate temperatures need to be during heat treatment either, particularly for the hobby bladesmithing I do.  I guess if you are flirting with the edge of the austentitic range, trying to ensure full conversion without excessive grain growth before hardening, or wanting to temper back to a specific Rc level, actual temperature and stability of same could be important.  Of course you could also just use decalescence for the former, but I still have trouble seeing that in my forge chamber.  Probably tend to run it too hot...  Hmmm, maybe I should use that IR gun a bit more.

People say, "you shouldn't," to me an awful lot you know. I sometimes don't even read posts let along reply. However you were joining an ongoing thread with good, 1st. hand information. A laser pyrometer usable in or near a propane forge is pretty valuable. Knowing how to use it to maximize accuracy even more so. 

I don't harden or temper often enough to have a favorite method of determining temperature. Having just now looked up decalescence maybe I do or did use it. I "usually" heat to what I call firey or flickering yellow, the steel appears to flicker with different shades of yellow like a flame is flickering in it. Hotter and it's just consistent, bright or high yellow, cooler and its just low yellow. 

Not all steels show the flicker either. 

A tool to take the need to "see" the cues would be a good thing. Especially for someone who only hardened and tempered rarely and never for blades. Heck, I'm tempted to guy one and I don't spend much time at the anvil at all anymore. 

Frosty The Lucky.

 

18 hours ago, Frosty said:

I suppose that's true Mike, I tend to range between nice old grandpa type to cranky crab old coot. Too bad for the annoying youngsters around us eh?

I find everything fails with age. Even my impatience with youngsters

Hmmm, maybe I'll refer the annoying ones to you then.

Actually my bout with cellulitis a few months ago has effected my thinking noticeably, especially short term memory. On the up side I survived a severe bout of cellulitis in only 4 days of IV antibiotics in the hospital. It has a considerably higher mortality rate than Covid even though it's bacterial and responds to anti biotics.

Still lucky after all these years.

Frosty The Lucky.

Well thank goodness for that.  My memory sucks also, though I don't have a good excuse.  Glad the antibiotics worked for you.

Thanks, it was close. Deb had gone to a dog rally about 270miles from here at my insistence. I was sick but not bad enough for her to miss the rally. She called a friend of ours who dropped by for to check up on me. She's a long time RN and after talking for a while I decided to ask for a ride to the hospital. Had Jean not come over I don't know if I'd been able to call 911 in another day.

I went from thinking maybe I was coming down with something to nearly incapacitated in 3 days.

What I don't get is how I got it, it's not contagious nor infectious. Sick as I was I did the pull my glasses down and peer at him over them when the attending physician said that to me. I was way too ill to grill him on that little bit of impossible. Non-contagious . . . Okay. But how in HECK can you be infected by something that's not infectious? 

Sorry, I still don't know for sure what I had, my general hadn't gotten the results of the bloodwork last time I visited her.

I wish Slag were still posting, he had the certifications to search subjects medical and was good at answering questions in lay terms. He was great for bouncing my questions and frustrations off without getting ticked off like I do. 

On a positive note, it seems hospital food has improved, it's not all starchy glop!

Frosty The Lucky.

Very glad you got help at an opportune moment.  I am hardly a medical professional, but the Cleveland clinic site appears to have some good info on cellulitis for the layman: https://my.clevelandclinic.org/health/diseases/15071-cellulitis .  Sounds like something that I will have to look out for also.  Appreciate the warning.

Back in 2007 I developed a cellulitis infection due to an infected tick bite to my R lower calf. I know exactly how I acquired it, by scratching the tick bite when my hands, finger nails were dirty from welding some old wet rusted pipe, so I picked up a staff infection.

I tried treating it with over the counter antibiotic cream, I think Neosporin. After about three days with no improvement, Debi forced me to see my PCP. He took one look at it and sent me directly to the hospital. The Cellulitis had turned into a MRSA infection.

I spent 7 days in the hospital in an isolation room with, I don't remember how many, IV's and on the 5th day my doctor said if it isn't responding by tomorrow, we will send you to the hospital in Springfield. I asked him what can Springfield do that you can't. Being the funny guy that I loved, he calmly said amputations.

Fortunately I showed improvement on the six day and was released on the seventh, with daily check ups at the clinic for a couple of weeks. Debi had to play nurse and change the dressing and put on a new one with SSD ointment 3 times a day, until it was completely healed. The infection compromised the veins in my leg and I have to wear one of those hospital compression hose or the ankle and lower calf will swell up like a balloon. I really dislike the compression hose and every once in a while I threaten to stop wearing it and Debi convinces me to continue wearing it or suffer severe bodily harm, without going into detail but I get the message.

I can't control the wind, all I can do is adjust my sail’s.
Semper Paratus

 

That's a good article, thanks. Now I'm really curious how I got it this time. 

I had cellulitis once before but I know how I got it that time, I'd kicked something out of the way and stubbed a toe in my boot. No biggy, it didn't hurt but within half an hour it was painful, hot and swelling. One look at the red streaks running up my leg and we were off to the hospital and IV antibiotics.

One toenail had nicked the toe next to it and I was in trouble in maybe an hour. 

I wish I knew how I got it this time.

Frosty The Lucky.