Polar 137X - cutting problem - not holding dimension

[GlobusoN]

First of all want to say "Hi"

I am facing an issue with proper cutting..
Depends of material:
- paper is OK
- heavyweight paper - NOT OK - after cutting when you check dimensions cards which are in lower part os stack they get bigger size.

I assume some problem with hydraulics but can't find diagrams.
I have read in this forum that the pressure valves are doubled for safety reasons, so as I understand it is hard to diagnose the failure of the valve.

Can someone provide diagrams of hydraulic system??
Maybe some clues to fix my problem??

Stay safe and healthy

 

[TVI]

Good afternoon!

The problem description lacks sufficient information to draw a definitive conclusion.

When you press the lower pedal to lower the clamp, the hydraulics apply a "safety" level of force. When you are about to cut a full stack of cardboard and set a high pressure value, the hydraulics apply strong force. This difference is visually apparent. If there is no difference, the issue likely lies with one of the clamp valves.

If the difference is visible, the solution is simpler and does not require replacing parts.
I assume you have ruled out the primary cause of most issues: a dull blade.

First, check the vertical alignment of the backgauge by making a test cut on paper; there is an adjustment for the vertical position.

Second, you can adjust the time delay between the clamp lowering and the start of the blade stroke. The clamp needs enough time to squeeze the air out from between the sheets and firmly secure the stack; this prevents the blade from pulling up the top sheets. You can change this timing in the machine's menu simply by selecting a numerical value.

Third, you can prepare the paper stack. The machine's menu allows for clamping the stack without cutting. You can set the pressure and—for example, every 50 cm—press the cut buttons to expel all the air from between the sheets beforehand. You can also write a simple program to specify the interval at which the clamp lowers, the duration of the clamping, and the amount of force applied.

Everything is described in detail in the operating manual.

Good luck.

 

[andy martin]

Check clamp pressures, blunt blade and knife bevel, if needed grind knife with double bevel