Despite its important role in the screen-printing process, the squeegee often doesn
Squeegee angle Angle adjustments can be made to produce different print results. Generally the idea is that the greater the angle (relative to perpendicular with the screen), the heavier the deposit, and the lower the angle, the thinner the deposit. There is no right or wrong setting here. What you are looking for is the appropriate settings with respect to the substrate, ink, mesh, and squeegee durometer, and the desired print characteristics. What you need to do here is to consider all of the typical variables in your shop and use them to establish a zero point for your squeegee angle. This means the angle at which all of your squeegees will be set before setting up a job.
In my shop, we print with a range of squeegee angles from 5-30° of perpendicular, but most of our jobs fall in the 10-15º range, with an occasional adjustment up or down 5º. Therefore, we have established our zero point as 10°. Establishing a zero point for squeegee angle is a process of trial and error. But once you determine it, document the setting and implement it as part of your standard setup process.
Squeegee pressure Press operators love squeegee pressure. It seems to be the answer for most on-press issues. The reality is that adding squeegee pressure is only a quick fix, rather than a so-lution for a bigger problem. Don’t get me wrong, sometimes adjusting squeegee pressure is the solution. But all too often, it becomes excessive, misused, and printers form the habit of maxing out squeegee pressure.
Excessive squeegee pressure leads to screen breakdown, wear and tear on your press, misregistration, excessive dot gain, poor image detail, and a host of additional problems. The goal is to print with minimal squeegee pressure. To determine your zero point for squeegee pressure, follow these steps;
1. Load an imaged screen (preferably a full size image of approximately 12 x 12 in.) onto your press, and load ink onto the screen. I suggest using your most commonly used all-purpose white plastisol, making sure the ink is thoroughly mixed.
2. Load a new squeegee along with a floodbar into the print carriage. Be sure that your floodbar is adjusted so that it barely makes contact with the mesh. Make sure that the contact is even from side to side.
3. Set your squeegee angle to the zero position you established earlier.
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