I would not trust it. A dial indicator attached to the print carriage is way more accurate at leveling the pallet to the print head.
Two dial indicators attached to a device that is attached to the sq/fb carriage is the best I've ever used. Using dial indicators on something that rests in the screen holders will likely get you a high tolerance compared to what I've seen done by every equipment installer but I'd start by getting the pallets parallel to the carriage rails then bring the screen holders into play. Speaking of this, I REALLY need to calibrate our press.
Hi Alan:
Thanks to you and everyone else for the replies. We have developed an new way of machine calibration using a similar approach.
Firstly we will level the squeegee carriage to a pallet.
Then we will level the frame holders to the calibrated pallet.
Then we will register the pallets to the 1st registered screen holders.
The key to this new approach is a special pallet which allows shims to be magnetized into position. Magnets are embedded in the bottom which hold the yellow shims in the picture.
The system includes 4 shims of four thicknesses - 1/16th, 1/8th, 3/16th, and 1/4".
You place specific thickness shims on all four corners of the pallet and then while your screen holders are already floating - you clamp the upper frame assembly to the pallet.
Then you tighten your screen holder adjustment nuts and you're calibrated. It's much easier than 4 dial indicators on each corner.
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