"He who marches out of step hears another drum." ~ Ken Kesey
I hate to be the bad guy here but if your printing on a manual you got to rotate anyway...you might find flashing each color might be best and I don't think it will kill your speed that much if any. Once you get moving your pallets want be that hot, you would be very surprise at how printers flash every color, they might not admit it but it happens.darryl
How are your rotations changing so much based on flashing vs no flashing? I rotate my platens one full rotation before I rotate my screens regardless of the print. Even if you are printing top colors wet on wet, you will be flashing your base, so the only way you would change rotations would be not rotating the platens after the fourth print for each color, which would save you at most a bit over a single rotation of the platens in total during a 5 color job with a base (1/4 rotation per top color for 1 1/4 rotations of the platens after the base is flashed). That may seem substantially more efficient, but you are still rotating your screens during that fourth shirt, and you can rotate both at the same time in essentially the same amount of time, meaning you aren't actually saving any time by doing it that way. If you are rotating your platens only twice in total (once during the flash, and 1/4 per shirt then printing all top colors one shirt at a time), it means you are rotating screens a ton more times than necessary which is far less efficient than doing all of a single color at a time on all shirts, then moving to the next color. I have done time tests on this, and in every scenario it is much faster to rotate shirts printing a single color at a time than it is to print multiple colors per shirt then rotate shirts. This makes the flash vs no flash point moot. Moving the platens more is faster/better than moving the screens more for a lot of reasons. First, you are putting sideways pressure on your screens fewer times during a run, which lowers the probability of moving one out of registration. Second, it allows you to use one hand to hold the screen slightly up and one to turn the platens in a method that minimizes the up and down motion of your screen and speeds up the time between print strokes. Third, you are trying to get the screens lined up to the registration gate for every print of every color instead of just the first print of each, which inevitably will cumulatively take longer than having those screens already in place vertically. Fourth, the rhythm of your process doesn't change depending on the number of colors or type of ink etc. which means you simply get better at it in the long term due to muscle memory and the ability to tweak the fine movements of the process. This last one has been huge for me, and I have really seen it come into play recently as my jobs have gotten larger and more complex.I only do wet on wet when it aids in the blending of the colors for art reasons, or when doing waterbased prints where I simply don't even have the flash turned on.
The large open areas you're trying to print WOW aren't doing you any favors, and everyone has already mentioned the most important factors but there are several causes to buildup. The biggest one is the ink itself. I've been told so many times that an ink was WOW compatible, especially the brands that aren't named Rutland, Wilflex, QCM, One Stroke, WM Plastics and a few others, but the inks that are made and then rebadged have proven in my experience to be much less WOW compatible than the major players. Second issue which Danny mentioned is HEAT. It's your enemy in WOW printing. The third is screen tension, the fourth is mesh count, and if you have all those ducks in a row, you're good to go.
I am more inclined to think that you are not flashing enough. How long are you flashing, what's the distance to the flash and what is the platen temp?
Author
Topic: Wet-on-Wet Screens Sticking (Read 9754 times)
