Hello All,
We have begun testing engraving some plexiglass with small text. (1/4inch plexiglass, with 10point font)

Here is the issue:
The job starts out ok.
However, as the engraving job progresses, the bit cuts just a little deeper each time it engraves a line.
So, half way through the job, the bit has punched a hole through the plexiglass and is ripping apart the stickypad underneath.

Here are the specs and variables:
Machine = Chinese 6040z CNC
Toolpath design Software = VCarve 8
Machine software = Mach3
Material Table = very thin stickypad mounted to the aluminum CNC table (this is not likely causing the issue)
Material being milled = 1/4 inch plexiglass
Bit = fine needle bit (not sure of the lingo to describe)
Intended engraving depth = 1.25mm

I guess my question is, has anyone else ever ran into a similar issue, and what are the most common causes?

Thanks...

Mark