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screen printing => General Screen Printing => Topic started by: Shanarchy on August 26, 2019, 11:43:41 AM
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I finally got a donut probe (Aquatuff Screen Print Kit, includes 35100-K, 50008-K). Probably should have gotten one years ago.
So I am not sure if I am using it correctly. I put the cross hairs over a print, tried to kinda push it into the ink a little. At mine normal settings I got a peak reading of only 240 degrees. To get it to peak at 330, I needed to slow the dryer down to a crawl and definitely had to be over curing and was scorching the heck out of the shirt.
Anyone have any idea what I'm doing wrong?
Thanks!
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Put it in side the shirt with the cross wires up. that way you know the temp all the way thru
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Put it in side the shirt with the cross wires up. that way you know the temp all the way thru
Good thought. I didn't even think of that. And that would allow me to measure the temp without messing with the print.
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You want to measure the ink film. So put the cross on the imprint.
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what rick said to do will show the temperature that the base layer of ink will see. ive always understood the important part is to fully cure the underbase ink.
ive measured the dryer temp with many methods - inside the shirt (for the base layer of ink) , on the ink (ink film temperature), cross hairs in the air (air temperature)...
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But, if what Shanarchy says is true, about not reading above 240 actually in the ink, at his normal cure settings, inside the shirt should read even lower! Can't wait to see how this plays out!
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As Frog suspected, inside the shirt I'm getting around 195.
Dryer (Vastex EC2) shows the tempt to be at 845.
I have 2 different infrared temp guns reading the ink on the shirt to be peaking at 380-400.
If I put the donut in the dryer and leave it there, under a panle it won't go above 217.
Anyone have any thoughts?
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Any chance you're in Celsius and not F? 195C = 383 F
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i looked at the specs and the AquaTuff has a range of -40° to 400°F (-40° to 205°C) with probe. to get 240c it would be out of range...
hmmm...
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https://www.youtube.com/watch?v=CT5YBqzAdBo (https://www.youtube.com/watch?v=CT5YBqzAdBo)
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.... just spit-balling. Could you place the probe into boiling water to see if it reads 212 degrees ?
That would give you a rough guess about it's calibration.
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DSH:
Definitely in F. That was the first thing I double checked. It seems to read standard room temperature correctly.
Zelko:
I went with the 35100-K, which is supposed to be rated to 999 degrees Fahrenheit.
https://www.cooper-atkins.com/products/35100-k-aquatuff-waterproof-thermocouple-instrument/ (https://www.cooper-atkins.com/products/35100-k-aquatuff-waterproof-thermocouple-instrument/)
Northland:
That was my next thought was to try to test it with other things and see where it puts the temperature at.
BP:
This is what I tried first. Then inside the shirt second, which yielded and even lower temp.
I should probably call Cooper-Atkins and see what they advise. Figured I'd try to cover my bases first in case i was missing something on my end.
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As Frog suspected, inside the shirt I'm getting around 195.
Dryer (Vastex EC2) shows the tempt to be at 845.
I have 2 different infrared temp guns reading the ink on the shirt to be peaking at 380-400.
If I put the donut in the dryer and leave it there, under a panle it won't go above 217.
Anyone have any thoughts?
I wouldn't rely on the infrared guns for those readings.. Send the donut probe through (crosshairs up) entire dryer and see what you get. See if the temp goes up toward the end of the interior. That's what we always see. When I test, I usually:
1. Divide belt into three sections (left middle right)
2. Send the donut probe through crosshairs on the belt (I know you could do up also, but just always put it on the belt..)
3. Take readings along the way and graph
4. Voila, your temp profile for that section.
5. Repeat
Back to the temp under the shirt, I'm thinking that might be the actual temp?!? meaning, it's reading low but could be right. I feel like those donut probes are pretty accurate.
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Shanarchy, I would call Cooper-atkins. But I would also talk with your ink company and see what they have to say.
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Northland:
That was my next thought was to try to test it with other things and see where it puts the temperature at.
BP:
This is what I tried first. Then inside the shirt second, which yielded and even lower temp.
I should probably call Cooper-Atkins and see what they advise. Figured I'd try to cover my bases first in case i was missing something on my end.
I went through the exact same thing. There is like a 40 degree difference between the probe and the temp gun. If I wanted the underside of the print to reach 320 then I'd have to scorch the shirt.
Although, probably not recommended, I just went back to using the temp gun and when the top layer reached 360/375 I just assumed that the base would be at around 320. I've never had a shirt come back uncured except once when I was printing silver metallic.