[Bertho]

To get uniform cutting depth the laser power needs to be proportional to the actual feed rate which will vary as the laser head accelerate and slows down. This is commonly done by pulsing the laser on for fixed power burst every time it moves a fixed distance. For example it can fire every 0.1mm (4mils). So by first setting the power level by the duty cycle modulating the laser by for example 25% duty cycle and then pulsing it every time it moves the fixed distance the cutting power will be uniform.
After that long introduction comes the question: Can the Mach-3 software do the proportional pulse control? If not what suggestions do you have? I can always build a little embedded controller looking at the X-Y movement and calculate pulses based on that but I really do not want to spend the time doing that. TIA for any suggestions.
Bertho

[zax15uk]

I think it can vary the power with the laser/plasma add-on, but maybe someone else can confirm as I haven't used it for this purpose. With the right interface that could be converted to pulse width to do what you suggest.

Most lasers have very low inertia compared to CNC machines so the acceleration/deceleration is much faster and combined with constant contouring (look ahead) it should ensure a fairly even depth.

Zax.

[samco]

With emc2 I think you could do something like that. You could take the velocity of the tool and scale it then output it as pwm in hal. (just thinking big picuture.) But there might be other Issues I am not thinking of.