SuzukiGS750EZ
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What's a fairly accurate, not overly expensive heat gun for use in the automotive field. No truck brands please. I'm looking to spend 50$ or less.
Infrared thermometer
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SuzukiGS750EZ
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Well I also wanted to use it around the house, but automotive would be worth it enough. I'm talking about the ones with a laser dot. Non contact.
bob from indiana
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I have one from Harbor Freight. It was around $25.00 with a coupon. It works well for what it is. I have used it a lot for cooking and keep it in the car to check the road temp. on wet mornings in the winter. It is interesting to look at radiator temps and thermostats as an engine warms up. I would buy another on if it broke.
The laser dot is only a pointer, it has nothing to do with measurement.
The best units on the market, take a large plate out of your cupboard, at about 3' from the unit that's the spot measurement size, it averages every temperature in that area for your reading.
The worst units on the market, take a hula hoop(not kidding), at about 3' from the unit that's the spot measurement size, it averages every temperature in that area for your reading.
Most manufacturers will not explain any of that easily because they would never sell a unit but, if you ask the right questions they will cave.
You're exaggerating and who's taking measurements at 3 ft on a car? Resolution on mine is 1" circle at 12" distance. Use it all the time for air conditioning, checking parts while pre-heating for assembly, checking coolant temperature to verify the gauge, etc...
rlitman
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You're talking about the D:S or distance to spot ratio.
Cheap units are 6:1, where at 3' away, the measuring spot is 6" across.
One of my Raytech units is 8:1, and another is 10:1. I have a different brand that is 12:1 (so the spot size at 3' away is 3"). The best units out there are 20:1.
When I have watched anyone showing off how great the unit they bought is for the automotive guys I see 3'-5' from the object they believe they're measuring, the industrial guys are really laughable, I'd say an average of 10'-12'.
Also, every single person that I've ever seen or talked to with a thermometer believed that the magic red dot (laser pointer) was actually taking the measurement.
I highly doubt your unit is as accurate as you believe but, if you want to have fun you can easily do some labs on your own in the house or garage with it and an accurate contact thermometer without endangering yourself and have some fun.
Schurkey
Well-known member
The other "dirty secret" is the emissivity of the "hot" object isn't standard; emissivity varies with material and coating--paint, oxide, etc.
http://en.wikipedia.org/wiki/Emissivity
Some few thermometers have adjustable emissivity to match what you're measuring...but...how do you know the emissivity of what you're measuring? Right, you take a guess and hope you're more accurate than the "non-adjustable" thermometers.
Infra-red non-contact thermometers cannot be considered accurate. They're at best "repeatable".
http://en.wikipedia.org/wiki/Emissivity
Some few thermometers have adjustable emissivity to match what you're measuring...but...how do you know the emissivity of what you're measuring? Right, you take a guess and hope you're more accurate than the "non-adjustable" thermometers.
Infra-red non-contact thermometers cannot be considered accurate. They're at best "repeatable".
JonnyMac
Well-known member
I have a fluke... its pretty awesome plus it has a thermocouple port if you want to use a tc..
If you believe in it and like it then by all means keep at it, if you really need accuracy then you have a problem.
If you're actually using one you're maybe 6" away... As for resolution if you move the unit an inch to the side (I did this on an exhaust manifold awhile back) it will drop from 650 degrees to 160. That's just shifting the aim from the manifold to the block. Now if it's averaging a plate sized area explain that...
Everyone knows it's not accurate to tenths of a degree, that's not what it's for. If the engine fan turns on all your readings go to hell... It's just for getting an approximate temp and they work great for that.
You just hit on a little, there is much more information and it's just a google away.
I could go on for days but, unfortunately I'm a hunt-n-pecker so I'm already pooped out.
If you are under hood 6" away why can't you take an accurate contact measurement?
Pawl
Active member
I bought a cheap one at Sams Club last year. It works great for checking the bearings on my round baler.
I have a Fluke 62max, you can adjust emissivity and has a 10:1 spot. I'm not using for any critical work but it gives you a good indication on temperature differences. Got as part of a package deal for $140 that included a laser distance meter and a non-contact electrical tester. Don't have any clue if it's better the a HF job but I would put my trust in Fluke, as they have never let me down before.
rice rocket
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You guys are making a big deal out of nothing.
He needs this for automotive use, which is usually taking temperature differentials between cylinders, or finding dragging brake pads, etc. He's not calculating the kilocalories released from his science experiment here.
Get the cheapie one from HF, it'll satisfy your needs 100%.
He needs this for automotive use, which is usually taking temperature differentials between cylinders, or finding dragging brake pads, etc. He's not calculating the kilocalories released from his science experiment here.
Get the cheapie one from HF, it'll satisfy your needs 100%.
OP
SuzukiGS750EZ
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RISC, about how many degree difference? Not that I need it down to tenths, but 5° is a lot when I'm looking at certain issues.
Mohawk Dave
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That Klein that Woodstockev did a review on looks badass. $120ish IIRC....and I looked at the M12 one, but at $200,,,meh.
Carves
Well-known member
I looked at a bunch of the things a while back.
In the end I decided they were only one step up from the,
owww, thats hot ... hand on the surface method ..
... but I ended up throwing some money at one of these.
It was cheap enough, and small enough ... to get in and utilise its 1:1 distance to spot ratio ..
For more accuracy, I use a multimeter with a probe - or another temp gauge I have, with a couple of thermo couplers hanging out of it.
In the end I decided they were only one step up from the,
owww, thats hot ... hand on the surface method ..
... but I ended up throwing some money at one of these.
It was cheap enough, and small enough ... to get in and utilise its 1:1 distance to spot ratio ..
For more accuracy, I use a multimeter with a probe - or another temp gauge I have, with a couple of thermo couplers hanging out of it.
Mechanical Noise
Well-known member
Harbor Freight spot size ratio is 8:1. It says so near the beginning in the manual and they give a clear illustration.
Have to wonder why "most manufacturers" aren't a clear as HF.
blackedout12v
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gotta disagree with ya on this. pulling truck developed a dead miss, on a cold start up monitored each exhaust runner(on manifold) and noticed #1 was drastically colder than 2-6, like 50 dgrees colder. 90 compared to 140ish on the others. told me #1 was the problem and it was. #1 plunger in the injector pump was the issue. this was easiest way for me to tell which hole the problem was in. HF $25 infrared gun paid for itself in that moment, among other various uses i have found for it.
blackedout12v
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x2.. well said
Schurkey
Well-known member
Forgot to mention in my previous post--when it was MY money, I bought Mastercool. I got mine years ago, but I think it's this model:
http://www.amazon.com/dp/B000OCKHGQ/?tag=atomicindus08-20
Adjustable emissivity, 30:1 spot, thermocouple jack, and "free" regular thermometer.
http://www.amazon.com/dp/B000OCKHGQ/?tag=atomicindus08-20
Adjustable emissivity, 30:1 spot, thermocouple jack, and "free" regular thermometer.
Canadian Charlie
Banned
Have a look on eBay thats where I got mine from
60:1 for Fluke's top-of-the-line IR thermometer. It'll cost you well over a grand retail.
engineer2
Well-known member
I've got the $40 Fluke 62 and it is fine, but as said, try to remember the Spot to Distance ratio. It's in the specs, but I forget.
Raytek had a nice idea with using a prism to make a circle of dots for the target area, but they can no longer make it. They lost an $8 million lawsuit to Omega Engineering who "drew" the target circle with an electric motor (a stupid design). Omega was a very litigious company when the Hollanders owned it.
Keep in mind conventional IR thermometers don't do well on aluminum.
I finally got a thermal imager for $200. Pretty decent for the price. Haven't had a chance to use it much.
Hot Dog!
Raytek had a nice idea with using a prism to make a circle of dots for the target area, but they can no longer make it. They lost an $8 million lawsuit to Omega Engineering who "drew" the target circle with an electric motor (a stupid design). Omega was a very litigious company when the Hollanders owned it.
Keep in mind conventional IR thermometers don't do well on aluminum.
I finally got a thermal imager for $200. Pretty decent for the price. Haven't had a chance to use it much.
Hot Dog!
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