Answers to frequently-asked questions
How Important Is Squeegee Speed?
The speed of the squeegee affects the rate of ink flow into the mesh openings. With plastisol inks, the faster the blade is racing, the less the ink will penetrate the mesh. In such cases, the printed image will be poorly covered. You could say haste makes for a full reject box. But yet again, we must qualify our statements.
You will not be able to speed your squeegee if your ink is too thick. You can either reduce the ink (use a curable or finished reducer or soft-hand extender) or step up to a harder durometer squeegee to gain more shearing power.
Talking about shear, remember that plastisols change when they are stirred. As the ink is worked back and forth over the mesh, it thins slightly, due to the heat and agitation generated by the squeegee action. You may need to adjust the squeegee speed by the end of a long printing run.
On the other hand, water-based inks (including discharge inks), which are less viscous than plastisols, can be printed at higher speeds. In general, inks tend to print better with higher squeegee speeds.
How Much Pressure Can Your Print Take?
My first magic pull of a squeegee was a disaster. In my enthusiasm, I bent my back to the chore and gave it my all. Too much pressure resulted in misregistration. Where the design required knife-edge sharpness, I had printed a furry mess. The thick layer I had mashed through the screen never did cure properly, and I was wasting ink. I also learned that if I kept it up, the pressure would ruin the screens and even wear down the squeegees. I discovered that the best production runs are the result of a light touch--assuming all other factors are optimal.
Once correctly set, these factors--adequate screen tension, proper durometer for the mesh count, suitable ink viscosity, and minimal off contact--will allow you to make minor squeegee-pressure adjustments, resulting in the perfect print.
Think about it: The easiest component to change in a manual press run is the squeegee pressure. If part of the print is not covering well, use more muscle. If there are streaks, use more muscle. You sorta get an image of The Hulk, grunting as he flattens the squeegee and makes that *!ª#*?! ink do what it should.
This picture is all wrong. What you want is the least amount of pressure--think bantam weight, not World Wrestling Federation.
Can I Avoid Printing Pain?
Another reason to avoid heavy squeegee pressure is a disastrous spinoff of the age of specialization: carpal tunnel syndrome. This syndrome (characterized by tingling, numbness, fatigue, and/or pain in your arms and hands) can be prevented by rotating staff assignments in the shop, altering the squeegee grip and/or stroke direction, or padding the holder. SqueegeePlus! of Eugene, OR, manufactures an inexpensive, ergonomic neoprene pad that can be retrofitted to most squeegee holders. This pad changes the traditional pinch grip into an open-palm grip, thus reducing the chances of developing this debilitation.
What Care Do Squeegees Need?
In closing, a few basic tips on the care of your squeegees are worth listing:<P>If your squeegees arrive coiled, store them flat and away from heat. Blades should always be hung or laid straight.
Allow squeegees to rest between runs and before resharpening. Preferably, rotate them after 4-5 hr on the press. As Don Pierce of Washington, PA-based Pleiger Plastics recommends, "Develop a rotation program with at least three squeegees per station. It will keep your squeegees living 30-40% longer."
At the end of every press run, wipe and clean your squeegees with a mild solvent. Never soak a blade in ink or cleaning solvent.wisely choosing and caring for your squeegees, there should be fewer times you are faced with the oldest question in screen printing: Why won't it print right?!
Some manufacturers of squeegees and squeegee-related products
ACLA USA, PA 412-776-0099
A.W.T. World Trade, Inc., IL 312-777-7100
Apolan International, NJ 908-922-6570
Crown Art Products Co., Inc., NJ 201-777-6010
Fimor/Euroscreen, OH 800-531-5566
Encore Engineering, FL 800-922-5138
Majestech Corp., NY 800-431-2200
Miller Process Coating Co., PA 800-742-9170
One Stroke Inks & Supplies, KY 800-942-4447
Pleiger Plastics, PA 800-753-4437
Printer's Edge, Ltd., OH 800-467-3343
SqueegeePlus!, OR 503-484-6449
Svecia USA, Inc., NJ 201-337-7786
Unipur USA, NJ 201-680-9858
Unitex Ltd., England 44-423-862-677
Zim International, GA 800-241-8181
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