Questions for you laser guys - building own laser control

OK, im not entirely new to lasers, just CO2. Im building a CNC laser table.

I have a Laser Engineering M-55 sealed tube with the specs here

http://www.laserengineering.com/specs.htm


My Power Supply is a Universal Voltronics 700W LRC specs here
http://www.voltronics.com/products/LRC/index.php

I am building my own controls based on a PIC.

My questions are:

Should I run in pulsed mode?

What frequency should I run it at, or make it variable freq. ?

Should I control power output with duty cycle?

I got a little control board going playing around with different frequencies and duties, but it just doesnt seem quite right.


Any help on how to implement pulsing would be much appreciated.

Thanks!!!

Hi.
This is a little bit OT, could you say what is the retail price on the laser tube you have?

I've been playing with and modifying my Chinese CO2 engraver over the past month. It has a similar supply to the ones shown on your link.

With these lasers, they use a pot to set the max power for a given job, and the controller pulses the laser on and off as necessary during the engrave mode. There is very little "depth control" during a run, because 100us pulse will burn just as deep as a 1ms pulse for a constant laser power setting.

In the simple software provided with these lasers, this isn't an issue because they only perform engraving in simple black&white. There is no "depth" in a high contrast b&w image.

I am converting my engraver over to Mach 3 control, where I will have Z depth capability.

I am considering a modification that will improve the engrave depth.

The potentiometer is wired in such a way that the laser power supply is really being programmed with a 0 to 5V dc level. I will use a PIC micro that will have a DAC that puts out an analog level based on Z depth in the Gcode.

This should give me both on-off and depth control. Perhaps I'm way off base. If the cutting depth vs. power is non-linear, then it will need a to have a non-linear correction or lookup table within the PIC.

hello how are you, I'm finding out about build laser machine, although I hesitate to control card, which you recommend? I do not have enough money to buy Chinese T_T drivers, but if I have the tools to make laser tube,
leetro mpc6535 , tube laser reci 80W , It works with a frequency of 20k, but more details would have to see its description