Ink clogging in silk

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ChurchTheArtist
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Ink clogging in silk

Post by ChurchTheArtist »

Problem:
White ink on black shirt. I can push the ink through for a good two coats on the first shirt but when I get to my second and third shirts, the ink seems to be almost dried in the silk and won't push through.

Details:
I'm using Union Plastisol ink from Tubelite and it's brand new. I have printed a small order of shirts successfully then stored the ink in a cool environment for about two weeks and am trying to do a second print run. I mixed in an extender base/soft hand when I first started because ink was too thick. I'm printing on both 100% cotton and 50/50 blends. I'm using a new squeegee. I have printed on these shirts before with success. I'm using a manual press that has printed successfully. I'm using a 160 screen that is old but barely used (the company I bought it from is questionable).

I've already tried:
I've tried different offsets from a pinky's width to a dime's width; absolutely no difference.
I've tried various pressures; absolutely no difference.
I've tried adding more ink to the screen.
I've tried multiple passes wet on wet but it's only building up in the small spots unclogged.

Conditions:
I do live in central Alabama and it is still summer. My temporary shop is located in a large building the size of an aircraft hanger currently being used for large scale storage. It has 20ft ceilings, it's an all metal building, it's not insulated or air conditioned; I use the bay doors on the two ends to allow a breeze through when it gets too hot. For the past month, we've had consistent three digit temperatures with 85%+ humidity, all day every day. It has been overcast today so I was trying to print during the low 90 degree temperature.

Prior success:
I had been getting up at 3am and printing before the sun came out because the heat was unbearable in that giant oven of a storage building. I had had this problem before where after printing both white and yellow ink it would seem to marble in the silk, thus clotting and blocking the print but after adjusting my offset and printing a few swipes wet on wet with heavy pressure, I was able to get an even coat. After printing numerous successful shirts, I gathered the batches of thinned ink in containers and stored them in my air conditioned house for a couple of weeks. I keep the house around 72-75 degrees.

I am using the same batch of ink but it does seem slightly thicker as it likes to accumulate on the squeegee and not slide off onto the screen. Can this extreme heat/humidity be drying or thickening my ink? Does this mean I am going to have to add extender base almost every time I pull out the ink?

I have been told "use (X) chemical to clean the screens" but that doesn't help me prevent the problem from continuing. I have been told to add the soft hand and I feel like after cleaning the screen and then adding more soft hand it might help... but what is causing this? Is the effect of soft hand only temporary? Does ink naturally get harder and harder in the short course of a few weeks? Will I have to mix in more soft hand with each print attempt? I don't just need to know how to unclog my screens, I need to know what's causing this and how to prevent it so I'm neither cleaning my screens every other shirt nor going through gallons of softhand in months. Is there a better way to keep inks soft during storage?
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d fleming
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Re: Ink clogging in silk

Post by d fleming »

Try a more open mesh. maybe 120?
chuckielb
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Re: Ink clogging in silk

Post by chuckielb »

whats your off contact
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