I printed my first 2 color shirt samples today. Yesterday was white and that worked pretty good.
All materials are 94% cotton, 6% spandex except for the white which is a 100% cotton T. That is the closest I could find to t-shirt material at the fabric store. I purchased 7 different colors to try different things out.
The first one is just testing the color on a white T. The second one is yellow cotton with a single pass white underbase. The image on the left was an error when I selected the white mask only (damn scroll wheel on the mouse!) but it does show an area that didn't get the proper pre-treatment.
The third image is on a black cotton material and shows a lot of 'cracks'. Even though the material looked flat, when the ink started hitting it all kinds of 'fuzz' started popping up. Some of this was contamination that I noticed during the pre-treatment (dog fur, dust, lint, etc). When I pressed the material it all laid down funny and caused the cracks.
Not bad for a first print, certainly better then my first attempt on a Kiosk (I wasn't using Ripping software, printed directly from Photoshop lol).
Are you printing in 720x 720? Your White t-shirt doesn't seem to have very good saturation especially in the black (looks greyish almost). I find that 720 x 720 or less just isn't good enough in terms of ink saturation for designs with black print.
Your design on the black t-shirt looks like contamination for sure. I find because of the pre-treatment being so sticky that you really have to clean your heat press, teflon sheets and anything that can come in contact with the shirt.
We use a Lint roller on every shirt to try to remove fuzz and other contaminates before pre-treating.
Also, we do a pre-press step for 15 seconds at very high pressure and the pre-treating process we wipe it down with a foam brush which helps the fibers lay flatter. When drying the pre-treat we also use very high pressure to keep the fibers flat.
Keeping everything flat is the key to getting a smooth print.
DTG Kiosk, First Prints 
