Pressure values above 18 misbehave

[jnweiger]

When selecting a pressure value of 19 or more, the plotter scrolls the material back and forth for several minutes before starting the cut. This often exceeds the material size and has to be aborted manually.

This is the trackenhancing feature. It tries to imprint the surface structure of the rollers into the material before cutting, to improve the grip when cutting. We need to explicitly control the feature, and if so, specify the length of the movement.

A comment in silhouette/Graphtec.py says that values of 19 or more automatially enable trackenhancing.

[jnweiger]

For the meantime, I've limited the manual entry of pressure to max. 18.
085def8

[EtherGraf]

Just tested it with my equipment. (silhouette portrait)
If I set pressure to 33 there is no automatic trackenhancing.
I would propose to allow values up to 33 in the dialog and append a explicit warning for some devices.

[EtherGraf]

With 8309726 increased the max value to 33 and added a warning. So one can use the full possibilities of the device. If this leads to problems, one has to choose values lower than 18 manually.

[EtherGraf]

I have found the reason for this behaviour. The switch for track enhancing was defined the wron way round. So track enhancing was always enabled. With the second condition, pressure set higher than 19, it was enabled on the device. A third condition is a given usable length. Maybe on some older devices this value is set by default?
In commit 2c91a5b I disabled track enhancing by default. This should solve this issue.