It has come to my attention that there are rumors about the ROQ being incapable of printing with one stroke for each color.
It’s a preposterous assumption that such a high-end machine does not perform adequately for plastisol inks. The ROQ press is designed as well if not better than any machine that I have ever used, and it too can produce one stroke plastisol prints….BUT if you expect to just take it off the pallet and have it work perfectly without adjustments, you’re going to be disappointed.
We sometimes forget that manual printers can make adjustments as we go. We can fudge it more often on a manual; pull to the right or left to keep a print in registration, or add additional print strokes as we see fit. The idea is the same on an auto: making on-press adjustments to get the print just perfect. However, the goal on the auto is to get a shirt printed perfectly in one round with only one stroke for each color and, instead of being able to tweak each print while you are printing, you have to make all of the adjustments beforehand.
I remember when I first started printing on an automatic, after graduating from a manual printer to a press operator, the first thing I learned was that I had to tell the machine what to do!
“How come we can’t achieve a one stroke white?”
Quite frankly, no one can. The number one argument I receive about one stroke printing is regarding one stroke white, but I’ve never seen a white that could yield a pure white without a flash in between. Spot color printers will be the first to agree since a solid base is used for the foundation of the rest of the colors. Typically, adding a second stroke of white does improve the overall look, however, it will add more time for the machine to index to the next station. It also stacks the ink, adding more time for the area white area to gel. Eventually, we see the ink heating up and thinning out, and all we really have done is added additional time with minimal gain.
So what can we do to get closer to one stroke plastisol printing? It all comes down to tweaking and testing before you ever start printing.
Here are some things to consider when you’re struggling to get a handle on your one stroke plastisol printing:
1. Address the artwork.
Most printers will have to make changes and move away from full white underbases to, instead, use a white top layer to pop off the white.
2. Change up the print order.
Print the smallest area to the largest, or lightest to darkest. Choose lighter colors to print without base support. Rethink the placement of your black trap plate and move it ahead of your base plates.
3. Combine your techniques.
Rethink your techniques and combine simulated techniques using halftones with spot colors.
4. Modify your inks.
Move to a high opacity plastisol ink or ink mixing system and modify your ink per job. I have found 80% of all plastisol ink need some modification to run smoother.
5. Take advantage of your press.
Use even pressure for each print head, then use the manual down-force adjustment to dial in per screen. The ROQ advantage is this: central point consistent pressure throughout the print stroke. The ROQ press has a center out squeegee and flood bar assembly, unlike the traditional choppers which are located left and right for most of our competitors which can loosen up leading to uneven pressure from one side or the other.
6. Dial in your squeegee.
Use a different squeegee blade. Try different angles and speeds. Consider the attack or angle of the squeegee blade. Simply leaving the blade in one position is a recipe for mediocre results.
7. Be smart about your mesh.
Choose a mesh count that makes sense for the application. Lower mesh works best for thicker ink: 110, 156 and 200. Higher mesh works for more detailed prints: 230, 280 and 305.
8. Keep checking your prints.
Begin the print cycle slower and ease into speeding up the press. Repeat the process after breaks or extended times away from the press.
Achieving a one stroke plastisol print isn’t without work, no matter what kind of press you are using. The ROQ is no different. Like any automatic press, you can use your ROQ to do one stroke plastisol printing by understanding and following these key points.