# Curing Problem?



## DesignsToSigns (Aug 4, 2007)

How is everyone doing been a while since I have posted here as I have been real real busy which I think is a good thing. Of course my signs are taking off and with that I am doing more t shirts. I have never been the best at silk screening and each time I do an order I think after I am done I should just sub it out. But none the less let me explain my problem.

I am doing this out of my basement, I have a flash unit and no conveyor dryer. I guess the problem I am having is after a couple of washes I am losing the ink off my shirts. The real problem seems to be with the last order which was a two color shirt. Here is the process I did.

Screened the white then flashed it till dry to the touch and then screened the green. After that I moved it to another platten as I worked another shirt and flashed the two colors together for almost 22 seconds with my thermometer I was getting 250 degrees on the ink while the flash unit was putting out out almost 500 degrees. I thought about going longer but it seems like everytime I do that I burn a shirt.. 

Any help is apperciated. Thank you guys

Adam
Designs to Signs


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## identitylab (Jul 25, 2008)

the only way to realy solve this problem is by buying a dryer. a flasher unit will never cure the shirts fully unless there white shirts. even if you leave the shirt under the flasher for a long time u might just over dryer(there is a such thing as to much heat)


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## DesignsToSigns (Aug 4, 2007)

Too much heat will bring what kind of problems and the symptoms?


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## identitylab (Jul 25, 2008)

if its over cured the image will start to crack. and peel.


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## splathead (Dec 4, 2005)

You can properly cure both light and darks with a flash dryer.

250 degrees is not hot enough to cure plastisol ink. The ink must reach 325 or so, depending on the brand. With my fliash, I position the shirt 3 inches from the flash and leave it there for 45 seconds.


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## DesignsToSigns (Aug 4, 2007)

Splat to you ever have a problem with the sleeves or anything else turn brown or anything from the heat? I have had some even burn a mark in there. Just want to figure out how to really do this.


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## dann (May 27, 2008)

Yeah, 250 degrees isn't hot enough. Nor is 20 seconds long enough. 350-ish degrees for 40 seconds or more will do the trick.

I do all my cures with a flash. I figured 2 flashes was cheaper, and took up less space than a conveyor. I've yet to have a shirt wash out. I cure for around 1:10. Could be longer than needed, but I'd rather burn one shirt, than replace 40. 

I've burned up a few shirts on the press, but only if something isn't laying flat. If there's a wrinkle or the seam is higher than the rest of the shirt, it will get crispy and brown, but it's generally not a problem.


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## DesignsToSigns (Aug 4, 2007)

OKay my next question would be can I reflash these shirts if they have not been washed or dryed yet?


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## splathead (Dec 4, 2005)

astours said:


> Splat to you ever have a problem with the sleeves or anything else turn brown or anything from the heat? I have had some even burn a mark in there. Just want to figure out how to really do this.


Every once in a while when I am not careful with the time. The way to tell if your shirt is completely cured is to stretch the inked area after removing from the flash. If is stretches and does not crack, it is fully cured.

Browning is caused by the garment either being too close to the heating element or too long under the heating element.


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## splathead (Dec 4, 2005)

astours said:


> OKay my next question would be can I reflash these shirts if they have not been washed or dryed yet?


Yes, you can put them back under for curing.


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## DesignsToSigns (Aug 4, 2007)

So I guess my next question is what is your recommended time and height to properly cure with a flash unit. You guys have been a huge help.


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## lost1 (May 12, 2007)

*Why play the guessing game? Fellers has these also.
*

*Raytec "MiniTemp" Thermometer*

*Now with laser sighting!*








Just point, pull the trigger, and read the digital temperature display. Measure the temperature of hot moving objects from a safe distance. Takes all the guesswork out of curing inks. A must have item for every shop.

Temp Range 0-500° F
Special! $89.00


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## DesignsToSigns (Aug 4, 2007)

I have one that is how I knew what my current temperatures were, but I do have to say that is the best thing I have bought for screen printing.


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## lost1 (May 12, 2007)

Then all you need to do is use it to make sure the ink hits 325. Play with the height and time till you find the zone and then just use a timer.


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## Uncle John (Mar 11, 2007)

If you put down and underlay, you don't want it to cure all the way before the next color or it will crack and peel.


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## jackiebell (May 6, 2009)

Along that last statement, I am having a similar problem with the job I'm currently doing. It is a 5 color job with white under most of it as an underlay, but also as one of the colors. One of the screens is red with a halftone to make pink. The test shirts are fine and if I print just the red screen it prints fine, but when I get to the second shirt in production, the halftone gets really blotchy and uneven, ruining every print. I lost more shirts than I have extra so it looks like I am about to miss a deadline (today) for the first time on this job, and was up all night trying to figure it out. All I can think is maybe I am overcuring the white when I flash? It's not overcured initially, but I did two passes and flashed each one, so maybe the second one is doing it. Would that cause this? Does anyone have any other ideas? Or, better yet, any Gildan 2000 Irish green shirts laying around?


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## Outlaws#11 (Sep 19, 2008)

Try removing the shirt from the platen this will allow for air to flow under the shirt and should heat the ink faster. Generally I set my flash dryer about 3" above the shirt and cure for 1 minute. ( this is the amount of time it takes my flash dryer to get the ink above 320 degrees)


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## 13Graphics (Jul 20, 2009)

something isn't right if you're ink is 250°, and the shirts are burning.

Are you very close to the flash dryer?

I am curing with my flash unit about 5" from the shirts, and hit ~350° in 20-30 seconds. I've cured to 425° on some shirts before getting discoloration (when I was first experimenting).

Outlaws is right too. If you pull the shirt off, and set it on something else it will heat up faster. You could even take it off your platen, then set it on top so both front and back are on it. Just like if you set it on a table.

I have a stand next to my press that I put shirts on to cure with my flash dryer. It's adjustable, but about 4" lower than my platen at the moment. If I set the shirt on it so only 1 layer is on top it always takes longer to cure.

Also if you cure on your platen it will warp. I only flash on mine, and it's warped by about 1/16" already. I've flashed a couple hundred times maybe 8-12 seconds each.


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