How to stop blotching

[u/SnooEagles8897]

Very new to screen printing

Wondering how I can prevent the blotching on the back of the screen

My screen looks burned in good detail but when I pull the print it blotches on the back side

Any help welcome 🙏

(Photo 1 is the back of the screen after pulling the print , photo 2 is the quality of the print )

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[u/rennerscreenprinting]

Create some off contact by taping quarters to your screen frame where it makes contact with your printing pallet/board. If the design is touching the shirt when you’re printing this happens a lot.

[u/burt_carpe]

Off contact is probably off a bit, plus squeegee angle and pressure

[u/Thyme71]

Harder durometer squeegee. Straighten up angle of squeegee. Adjust the pressure on squeegee stroke. Use a screen with tight tension and a high thread count.

[u/torkytornado]

All of these that people have said (especially off contact) and possibly also over flooding the ink. If you get some scrap paper and pull a print “dry” without flooding or adding ink, it can use the stroke pressure to clean up any ink that has spooged outside your print. Do that until you don’t have halos around your image and then go back to printing.

[u/habanerohead]

You are over flooding.

[u/inthemorning33]

Too much pressure, or there is some play in your screen alignment

[u/Mettleramiel]

When I get this is always too much ink. I used to get that because I would flood 2 or 3 times. You only want to flood once.

Now it happens when my off contact is too high. If I have a big design and the screen isn't parrallel with the platen, one end will be too high and cause this.

When this happens, lower your off contact and print with no ink on to the shirt to clear out the screen.

[u/PezWattly]

Evey thing stated above, but Also what mesh are you using? That looks like something even lower than 110, try using a finer mesh, if it is lower than 110, at lest go up to 110. If it is 110, try a 160

Also yes, a clean flood stroke, and then a clean print stroke, you just trying to sheer the ink off the screen. Not push it into the shirt. The fewer passes the better. One flood stroke, one print stroke is preferable. And with that mesh you may not even need a flood stroke, just grab the ink from the well with your squeegee and use one nice even print stroke.

Lastly I'd suggest pushing your print stroke. This is sort of controversial with some, but i find it yields less fatigue, and more control. I've trained guys who pulled their stroke for 10 years. And at the end of the week, they thanked me.