Tools, Glorious Tools! #5 - The Pyrometer
Added 2018-02-26 10:56:47 +0000 UTCHey Folks,
A new TGT episode is now available, all about the shop made foundry pyrometer.
Cheers,
Chris.
-------------- Video Notes: ---------------
Amazon Affiliate links:
Cameras:
Panasonic GH5 - https://amzn.to/2rEzhh2
Panasonic X920 - https://amzn.to/2wzxxdT
Tools & Shop Products:
Ingot Moulds: http://amzn.to/2pfpgWz
K-Type Digital Thermometer: http://amzn.to/2FFuGUN
High Temp K-Type Thermocouple: https://www.ebay.com/p/27004725848
K Type Cable Connectors/Male Thermocouple Adapters: https://www.ebay.com/itm/364155774454
10mm Carbon Rods: https://www.ebay.com/itm/385153939655
Comments
Will do Pat - Cheers :)
Clickspring
2018-04-13 20:41:26 +0000 UTCChris, love the TGL series, fantastic information for us new guys! Keep cup the great work. Pat
Patrick Walls
2018-04-13 02:46:31 +0000 UTC*Note*: Take the following with a few grains of salt: I have ZERO practical experience with foundries - either industrial or home-made. Having said that, Tom Walker is absolutely right. I DO have a ROUGH idea of how infrared thermometers work, and even if you were to take the crucible out of the foundry, you're much more likely to get a reading of flames, hot gasses, or possibly slag that hasn't changed color enough to see very easily, than you are to get the temperature of the metal. Even if none of those are a factor, you'd only get a return from the top surface of the molten metal, which will absolutely be much cooler (relatively speaking) than the temperature of the other 99%+ below the surface, which is what you really need a reading of.
Jonathan Crider
2018-03-13 18:03:30 +0000 UTCInfrared does not perform well inside furnaces. And the ones capable of high temps are very expensive.
Tom Walker
2018-03-09 13:48:42 +0000 UTCVery cool Sebastian - thanks for the info :)
Clickspring
2018-03-07 20:50:36 +0000 UTCAnd the coolest thing about K type thermocouples: The "balancing line" is made from the same material as the thermocouple itself. So when you just twist together the two wires in the cable you'll get just another thermocouple. So you can keep the excess wire, remove the insulation from the other end as well, twist and optionally braze them together and you can use it like any other thermocouple to measure temperatures of whatever you want. So you might want to keep the cut off cable :)
Sebastian Rietig
2018-03-07 20:44:13 +0000 UTCNot sure mate :)
Clickspring
2018-03-07 01:54:31 +0000 UTCWill an infrared thermometer work at these temperatures? One of those point n' measure things?
Karl Mansson
2018-03-06 01:42:55 +0000 UTCI mean the probe and the digital thermometer, but I guess the frame too - I just followed my nose on that one :)
Clickspring
2018-03-04 03:43:12 +0000 UTCChris, you mean the piping and all, that is something
Ralph McCoy
2018-03-04 03:41:50 +0000 UTCYes it is a relatively widely used combination - Cheers :)
Clickspring
2018-03-04 03:39:47 +0000 UTCChris, was looking at myfordboy video for today and when he checked the temperature, could not see all of it, it looked like the same gauge you have here. Ralph
Ralph McCoy
2018-03-04 02:48:14 +0000 UTCSo pleased to hear you're enjoying them mate - will definitely do more casting vids, its such a fun process :)
Clickspring
2018-03-03 20:32:23 +0000 UTCI love this series. You have so much knowledge and skill, and for some reason I love watching you make the molds for casting. Love to see a video on that subject cause I can tell you definitely found some tricks.
August frost
2018-03-03 02:39:27 +0000 UTCThanks for the info Sebastian, I shall happily snip away in future! Cheers :)
Clickspring
2018-03-02 21:12:52 +0000 UTCHa ha! Terrific to have you on board mate :)
Clickspring
2018-03-02 21:10:59 +0000 UTCA thermocouple is not a resistive sensor like a Pt100 or a NTC/PTC. A thermocouple is a combination of two different alloys that will create a voltage according to the temperature of the junction. A Type K is made from a nickel and a nickel-chrome-wire (NiCr/Ni). At 1000°C the function creates a voltage of about 40mV. The thermometer has a high impedance input, so nearly no current flows through the thermocouple and no voltage is lost in the cable. So the length of the wire does not really matter on a thermocouple. The cable is protected by a glass fibre sleeving to prevent it from melting.
Sebastian Rietig
2018-03-02 20:24:46 +0000 UTCJust became a patron! Love the quality of work you turn out, see what I did there, keep it up.
Luther
2018-03-01 18:06:11 +0000 UTCHa ha! Cheers Mike :)
Clickspring
2018-03-01 03:29:08 +0000 UTCNot sure mate, its just an Ebay special: <a href="https://www.ebay.com/itm/NEW-10mm-THICK-CARBON-GRAPHITE-ROD-10x-300mm-LONG-MIXING-STIRRING-CARBON-ROD/281773690940?hash=item419b05503c:g:opQAAOSwgQ9VzljP" rel="nofollow noopener" target="_blank">https://www.ebay.com/itm/NEW-10mm-THICK-CARBON-GRAPHITE-ROD-10x-300mm-LONG-MIXING-STIRRING-CARBON-ROD/281773690940?hash=item419b05503c:g:opQAAOSwgQ9VzljP</a> - Cheers :)
Clickspring
2018-03-01 03:28:55 +0000 UTCI would certainly do so if there was enough interest mate - it does tend to make most peoples eyes glaze over a bit tho... - Cheers :)
Clickspring
2018-03-01 03:27:59 +0000 UTCHey Chris, just became a patron and looking through all the videos (everything you do is amazing by the way) and was wondering if in a future video in this series you would touch on CAD? Your models of your projects always look amazing.
Natan Getschel
2018-02-28 20:13:20 +0000 UTCSigh, another cool tool I now must build, thanks chris
Mike Oswald
2018-02-28 04:24:41 +0000 UTCWhat exactly is that carbon rod - is it something you could make? I mean, probably it's cheaper to buy it, but could it be done?
John P
2018-02-27 21:54:37 +0000 UTCCheers mate happy to be the crash test dummy :)
Clickspring
2018-02-27 05:33:15 +0000 UTCYou could also use carbon rods for air arc gouging. They are copper clad though, so might need to be seasoned in something that isn't mission critical before being used in your carefully weighed out alloy. If you don't need a lot of them a welding shop would probably give you a couple.
James Cuddihy
2018-02-27 05:32:00 +0000 UTC:)
Clickspring
2018-02-27 04:26:29 +0000 UTCI always kinda wondered how well sticking a thermocouple in molten metal would work, and now I know. You saved me a few nuked thermocouple leads and hours of frustration as well as providing the solution I didn't know I needed, Thanks Chris!
Clifton Ballad
2018-02-27 04:25:27 +0000 UTCCool
Adam
2018-02-27 04:02:20 +0000 UTCI'm not sure Damien - possibly the latter? Its quite a hard and brittle material, but not overly powdery.
Clickspring
2018-02-27 02:34:15 +0000 UTCGreat video as always! Are the rods that you use graphite or amorphous carbon?
Damien Miller
2018-02-27 01:48:53 +0000 UTCAll the best to you too mate :)
Clickspring
2018-02-27 01:27:03 +0000 UTCI see where you're coming from, my antipodean friend. I guess that cable resistance could well play a part in temperature reading, in which case the full length of cable would be beneficial... I hadn't considered that, Chris, to be honest but I am sure that the pyrometer leads will not be made from an electrically high conductor with a relatively low melting point such as copper, simply because they need to be rugged and to withstand temperatures way above the melting point of copper. So, we must assume that the pyrometer wires are made from a high melting point alloy, which carries with it (as a trade-off) a stated resistance of Ohms per Metre, so in which case I agree, that the full length should be utilised. I'm eagerly looking forward to the next Antikithera video, Chris... I play them back many times. All the best, Gordon
Gordon Burns
2018-02-27 01:10:15 +0000 UTCHey Gordon, all good thoughts - no chance of snagging any cable, the braided sheath ensures that it slides through neatly :) Re the extra cable length, I seem to recall reading somewhere that the length may affect the probe temp calibration - That may or may not be the case, but I figured I'd rather not chance it since I have no way to check the calibration once cut - Cheers :)
Clickspring
2018-02-27 00:48:07 +0000 UTCVery useful tips in this video, Chris. Just a thought but you could've fed a 'mouse wire' down the tubing from top to bottom, then drawn back the pyrometer cables, so that the cables and sleeving were totally enclosed within the tubing for their entire length, negating the chance of snagging the cabling during use. I know how neat you are, mate, and note the neatness involved in coiling up the spare leads... only why do that? I also know just how exacting you can be Chris. I guess that the pyrometer and cabling are designation-specific to the foundry temperature probe, so why not chop the wires much shorter and fit the plug so that the leads are just long enough to make connection with the temperature gauge, obviating the need for the redundant coil winding (which could have a detrimental effect, resulting in spurious and inaccurate temperature readings due to electrical inductance within the coiled conductor, not to mention the possibility of catching it on something and either damaging it, or worse still, damaging yourself. As I said, Chris, just a thought and not a criticism, mate.
Gordon Burns
2018-02-27 00:39:55 +0000 UTCYes of course: temperature reading stabilizes I should have know that
Ralph McCoy
2018-02-26 22:58:44 +0000 UTCIts hard to really know Ralph, but the carbon conducts the heat very quickly, and I generally leave the probe in the melt until the temperature reading stabilises - so I would be surprised if there was any meaningful differential/error - Cheers :)
Clickspring
2018-02-26 21:20:53 +0000 UTCChris, this carbon cover how accurate is it from the outside to the thermonuclear ? I guess it would be " in the ball park" 50 degrees or so is close enough or am I being too exacting ? Ralph I enjoy the video
Ralph McCoy
2018-02-26 21:05:47 +0000 UTCChris, this carbon cover, how accruct
Ralph McCoy
2018-02-26 21:01:02 +0000 UTCOK, terrific Vince - I have also put a link in the text above - Cheers :)
Clickspring
2018-02-26 20:02:42 +0000 UTCAll good mate :)
Clickspring
2018-02-26 20:02:05 +0000 UTCHa ha! Cheers Wes :)
Clickspring
2018-02-26 20:01:33 +0000 UTCThanks Harold :)
Clickspring
2018-02-26 20:00:27 +0000 UTCI was a bit surprised at how quickly it was destroyed too! Cheers mate :)
Clickspring
2018-02-26 20:00:12 +0000 UTCCheers Jon :)
Clickspring
2018-02-26 19:59:36 +0000 UTCNever mind, I found searching for graphite rod came up with the proper results
Vince Endter
2018-02-26 19:11:09 +0000 UTCWhere can I find the carbon rod? Do you have a link?
Vince Endter
2018-02-26 19:09:45 +0000 UTCoh my new vid was beginning to think the worst
Theodor Kristiansen
2018-02-26 13:40:15 +0000 UTCThanks as always, Chris. Warm workshop at 28˚ . Wish we could have those temps in the northern hemisphere. Oh, and clever knockup probe as well. Always thinking and fiddling you are.
Wes Baker
2018-02-26 13:10:45 +0000 UTCNice video!
Harold Donnenberg
2018-02-26 12:44:50 +0000 UTCYay a new video. Great as always. Without knowing about it i wouldn't have expected the need to make the carbon cover but great to see.
Paul Busby
2018-02-26 11:52:24 +0000 UTCVery useful video! Thanks!
Jon Ivan
2018-02-26 11:32:49 +0000 UTC
