[goblgobl]

I just started screen printing 4 months ago. I'm kind of new to the industry. I started printing a job today for some Carhart high visibility,lined sweatshirts. They are 100% Polyester. The setup went perfect. The line up and loading are perfect, and the first 20 or so are damn near perfect but i hit a couple of them that just seem to not want to accept the ink. Im using a 156 count mesh with a medium squeegee and a union soft hand black. Now the first ones are great looking and I had no problem printing them,(2 pulls) but then I started hitting a couple shirts that were almost ink-proof. Can someone help explain this to me?. I stopped early today so i dont ruin anymore 40 dollar sweatshirts. lol

 

[pixelwhisperer]

Hard to tell from the description, what happened. Is this a one color job? If i'm hearing you right, maybe the sweatshirts have alot of loose lint that may have clogged the screen. Did you add anything to the plastisol that could have it clogging the screen. Usually screens open up as the job progresses, not the other way around. I would recomend you use screen opener just make sure you run a scrap shirt after cleaning so you dont ruin any live product.

 

[pixelwhisperer]

Also once your screen gets muddy from over stroking. You have to clean it, run a scrap shirt and start again. also check your off contact. Sweat shirts require more off contact to keep screen clear of shirt.

 

[goblgobl]

It seems almost like the material is "different" to the touch but its the same sweatshirt is it possible that there is some kind of additive on the material or could the inconsistency of the material be causing it?

 

[goblgobl]

and no there is no fibrillation at all the polyester is very smooth but some feel smoother than others. i am also keeping the the screen very clean whiping it down every 3 or 4 pieces is there a special ink or ink additive used especially for polyester printing i should try?

 

[pixelwhisperer]

yes nylobond, but It is used so the ink will bond better after curing. not so it will bond initially

 

[goblgobl]

Thanks alot for your input I thinned my ink a little and i actually changed out my screen for a 110 with cap film. it seems to have helped alot, no more mistakes... thanks again