[breathingspace]

Garments I am using are 60/40 cotton/polyester (Hoodies) and I am using a heat gun to make the ink dry to the touch and then immediately putting it on the heat press under parchment paper at 305-310 degrees. I keep it under for 30 seconds, lift to let steam release for around 5 seconds and then repeat 2 more times. So the order is 30 sec - 5 off - 30 sec - 5 off - 30 sec.

I've experimented with temperatures and lengths and nothing seems to keep the ink from cracking when doing the stretch test. Any suggestions would be greatly appreciated... thank you.

 

[splathead]

Curing waterbased inks takes a couple of minutes. A heat press is not the ideal way to cure. Are you able to 'hover' your upper platen so it does not come in contact the with garment? Try that if you can for 2 and a half minutes at 350 degrees or higher.

It also helps if you use a more professional ink. Speedball is a hobbyist ink. You'll get better results with Matsui, Galaxy or even Permaset.

 

[breathingspace]

Curing waterbased inks takes a couple of minutes. A heat press is not the ideal way to cure. Are you able to 'hover' your upper platen so it does not come in contact the with garment? Try that if you can for 2 and a half minutes at 350 degrees or higher.

It also helps if you use a more professional ink. Speedball is a hobbyist ink. You'll get better results with Matsui, Galaxy or even Permaset.

Will try ! I also ordered Green Galaxy white plastisol which should be able to be cured no problem and should fix the problem as well. Just got super frustrated with the curing issues.

 

[splathead]

You still may have issues with plastisol if using a heat gun and heat press to cure.

 

[NoXid]

Plastisol can melt when curing with a heat press. Yes, it can be done right, but water base is easier.

First of all, stop with the constant press/lift/press/lift nonsense I used to do one lift in the middle, but stopped even that some years back.

As Splathead suggested, you should be pressing at a higher temp, but not too high, as that will damage the ink. I use 340 F.

But a compounding problem you are likely to have is that dark Polyester will sublimate, release its dye, starting in the low 300s, and that can discolor your screen print. If the exterior face of your hoodies are 100% cotton, as are some products from Hanes and ITC etc, then sublimation is easier to avoid. Much harder on something like 50/50 Gildan 18000 series.

I would try the temp you are using now for 2 minutes with no lifts, and experiment with increasing temp until you get sublimation, then back off from that and increase time until you get a durable print. (Of course, do test prints all over a scrap hoodie and then cut that up into individual swatches for testing time and temps.)

All that said, the sooner you ditch the Speedball, the better off you'll be. I like Permaset Supercover and Green Galaxy is nice too. PS is quicker easier to cure and a touch more opaque, but more $. GG is less likely to dry in the screen screen, but tends to get sticky when flashing. Of course, there are other professional inks, like Matsui etc.

 

[breathingspace]

Plastisol can melt when curing with a heat press. Yes, it can be done right, but water base is easier.

First of all, stop with the constant press/lift/press/lift nonsense I used to do one lift in the middle, but stopped even that some years back.

As Splathead suggested, you should be pressing at a higher temp, but not too high, as that will damage the ink. I use 340 F.

But a compounding problem you are likely to have is that dark Polyester will sublimate, release its dye, starting in the low 300s, and that can discolor your screen print. If the exterior face of your hoodies are 100% cotton, as are some products from Hanes and ITC etc, then sublimation is easier to avoid. Much harder on something like 50/50 Gildan 18000 series.

I would try the temp you are using now for 2 minutes with no lifts, and experiment with increasing temp until you get sublimation, then back off from that and increase time until you get a durable print. (Of course, do test prints all over a scrap hoodie and then cut that up into individual swatches for testing time and temps.)

All that said, the sooner you ditch the Speedball, the better off you'll be. I like Permaset Supercover and Green Galaxy is nice too. PS is quicker easier to cure and a touch more opaque, but more $. GG is less likely to dry in the screen screen, but tends to get sticky when flashing. Of course, there are other professional inks, like Matsui etc.

Tried a bit more experimenting this afternoon, the hoodies in question are actually 50/50 upon review. I tried the 340 degrees for 2 mins with light-medium pressure not lifting and it seemed to be better, but not exact. Still cracking when pulled a slight bit. That being said however, your reply has seemed to get me on the right track so thank you ! I will look into green galaxy and permaset for sure. It will just be getting them to my location as there are no screenprinting shops around me hah.

Once again thank you though ! Seems to be that I am on the right track.

 

[breathingspace]

Just want to post an update. Got the Permaset Supercover in white and oh my gosh its a life saver. No problems at all so far with the cures on the prints I have done so far, even the white on black garment which I was cursing before. 350 for 120 seconds has been doing the job for me.

Thank you for the suggestions, and I hope this thread can help someone that may be in my situation too.

 

[NoXid]

Just want to post an update. Got the Permaset Supercover in white and oh my gosh its a life saver. No problems at all so far with the cures on the prints I have done so far, even the white on black garment which I was cursing before. 350 for 120 seconds has been doing the job for me.

Thank you for the suggestions, and I hope this thread can help someone that may be in my situation too.

Congratulations!

Going forward, just be sure to replenish the moisture (water) the used ink loses to the air and mesh. I keep my working ink in a separate container from my fresh virgin ink, so I always have a reference as to what fresh ink looks and feels like. Early on I made the mistake of not doing that, and the stuff became impossible to work with, as I just didn't notice the gradual change over time as it dried out a bit more with every use. If you stir the ink around with a metal cake frosting knife, or the like, most of the big blob of ink should slide/fall off of the tool fairly easily--else it needs some water. Get the feel of it with that nice fresh ink so you can tell the difference later on.