Hi Sitzme,
The plugin’s ‘fire pulse’ width is limited (it is essentially the axis step pulse) and as feed-rate is reduced the spacing between pulses increases thus producing the ‘lack of power’ problem you are experiencing.
My solution was to use an external microprocessor (PIC chip) to digitally detect the ‘fire pulse’ then extend it’s width. The prototype is a bit crude (based on a partially populated circuit board designed for my RF laser controller) and whilst I have every intention to refine this design and post it as a project, like most things, work interferes with play-time and it has been pushed to the back of the queue. The design could, I am sure, be simplified (by not having the display) as the microprocessor automatically stores the last setting (for future use) and it is easy enough to set-up by experimentation with a test sample. It requires no changes to the machine as it connects in series with the 25 way LPT cable and is just used when required.
Some while back another member posted an analogue design for pulse stretching and this works well but had limitations on the range of available pulse widths so I opted for a digital solution which can easily extend the fire pulse width right up to the start of the next pulse no matter how slow the feed-rate. His design is here
http://www.prutchi.com/2012/02/04/co2-laser-engravercutter-addition-to-a-cnc-retrofitted-sieg-x2-mini-mill/I am working on another project at present and this will probably keep me busy until the springtime but if you can wait until then I will post full constructional details of a re-designed pulse extender before the summer.
Tweakie.
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