Squeegees and Angles
Squeegees have many shapes and sizes. They are all designed to “sheer” the ink from the mesh and transfer the ink to the garment. I’m not going to get too deep here as there is so much to cover and the manufacturers will send me tons of letters defending each size, shape, durometer, etc.
I use 70 durometer square edge squeegees with 2″ or less of blade extending from the housing. Set at angles between 75 degrees and 65 degrees, this does the job perfectly for textile printing. Proper screen tension (tight) and proper squeegee pressure does the job of “sheering” the ink. Do what you will, but this is how I would set up your press if I were at your place.
Take a look at high-end squeegees such as the “constant force squeegee”. Its blade is so small and it’s angled at 65 degrees (close to it). Clamped into the printer at 90 degrees and the rubber is auto set to the proper print angle. Yes, I know it takes a very level platen to take advantage of this great idea (not all can), but hey, right is right. If we can’t create a perfect environment now, at least we know what we are shooting for. Strive for it in every way you can, but take from this information as it is intended. That crazy shaped housing is focusing the pressure down the tip of the blade where it belongs.
Frankly, the next time you see your blades doing the “limbo” on press back off the pressure, as you are not helping yourself.
Flood Bars and Flood Strokes
Many know that the flood bar on an automatic press along with the flood stroke move the ink into position for the squeegee but many do not fully understand the more important task. Yes, the flood bar spreads ink along the length of the screen, but it also forces the ink into the mesh and “stencil well”. The Stencil Well is the thickness of the emulsion layer on the “print side” of the screen that holds the ink until the squeegee “sheers” that connection and transfers the ink to the garment. Remember our conversation about “proper screen drying”? Now you are putting that to work. This is why only a small amount of squeegee pressure is actually needed. You want as much ink as possible to be left behind on the garment and not scooped back up by the squeegee. You need to know this if you want to be a good Screen Printer. This is how Screen Printing is done. Now you know more than you did before about “high-density” printing. Funny how all this stuff is connected.