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screen printing => General Screen Printing => Topic started by: printguy on September 21, 2021, 07:02:53 PM

Title: Flash Problems
Post by: printguy on September 21, 2021, 07:02:53 PM
Having issues printing a 9 color design -  printing on a MHM 14 color with 3 flash units. Platens are getting hot to the point where the garment ls sticking to the screen & pulling up after flashing; both after underbase as well as the second. Suggestions
?
Title: Re: Flash Problems
Post by: Frog on September 21, 2021, 07:11:00 PM
Do you have cool-down stations? Fans at said stations?
Title: Re: Flash Problems
Post by: Nation03 on September 21, 2021, 07:34:54 PM
Fans in the cool down station or maybe add some buffer revolutions to allow extra time to cool.
Title: Re: Flash Problems
Post by: Maxie on September 22, 2021, 12:33:26 AM
What screens and squeegees are you using?
I print 9 colors with 2 flashes, 150 under base 225 top colors without problems.
Squeegee 75/90/75.
We don't have cooling stations.
I'd also check flash times, we print with pre heated palettes and minimum flash times.
Also check off contact.
Title: Re: Flash Problems
Post by: blue moon on September 22, 2021, 09:55:17 AM
few thoughts. . .
the ink will be sticky if it's under flashed or possibly overflashed depending on the ink type. Do some testing with higher and lower temp to see what's optimal.
For prints after flashes, slow down the flood stroke to the minimum and add a fan. That will cool down the print before you hit it with a squeegee.
Also, for very large images, you might have to make the platens really sticky to avoid issues.

pierre
Title: Re: Flash Problems
Post by: inkman996 on September 22, 2021, 01:35:05 PM
Like other said there is some tricks, such as using a delay on before the flood stroke if your machine has that function, that way a fan blowing across the print has some time to remove some heat. Sometimes ink sticking to the next screen after a flash can be to high of a flash and the ink is so hot it makes the emulsion and ink want to stick together. In the heat of the summer there is times you just have to run slower, or take breaks to allow the platens to cool off.
Title: Re: Flash Problems
Post by: printguy on September 22, 2021, 05:49:14 PM
Thanks all!
Title: Re: Flash Problems
Post by: Admiral on September 23, 2021, 10:32:48 AM
Like other said there is some tricks, such as using a delay on before the flood stroke if your machine has that function, that way a fan blowing across the print has some time to remove some heat. Sometimes ink sticking to the next screen after a flash can be to high of a flash and the ink is so hot it makes the emulsion and ink want to stick together. In the heat of the summer there is times you just have to run slower, or take breaks to allow the platens to cool off.

Ultra slow flood stroke will do it as the delay, I remember having to do that on the Diamondback 7 color we had, when I did 6 screen jobs...