Chinese CO2 cutter and Marlin

I am struggling to find technical info about driving these tubes. Nominally the laser is 40 watt and the power supply has several laser control inputs. One for safety but the other two are PWM input for laser power level and on/off.

I am currently using the PWM input to set the power and have the laser in what Marlin calls "pulsed mode". I made some small change to Marlin to make it work and all is good.

However I am now thinking that it would be a lot easier on the tube if the on/off was left on and I just changed the power from 1% to 100%. The reason I think this is better is that in order to produce the lased output you have to first create the plasma within the tube. This takes some time and requires a higher voltage (25kV instead of 15kV running voltage) plus the PSU itself takes 1 ms to respond to the on/off request. With the laser kept ticking over the plasma should be there and the laser power supply is running so it should be quicker to lase.

I cannot for the life in me find out how to do this in the Marlin source and am really looking for info or pointers or any input, maybe someone knows that I am talking crap (I often do)

It boils down to needing to set a prefixed low level of maybe 1% for the PWM signal and increase to 100% rather than the pulsed mode changing the other output control to the laser PSU.

I think you can get from the alibaba and other B2B platform.

The alibaba is a good B2B platform,but you can try other B2B Platform,such as the en.ofweek and the made-in-china

Hi
can you be more specific to how to change arduino sketch base such Merlin to control the laser power and interpret the g cod for cnc laser?,
Best regards

Have you looked here?

https://github.com/TurnkeyTyranny/buildlog-lasercutter-marlin

Edited 1 time(s). Last edit at 05/10/2015 06:51AM by paulnd.

Yeah,I think you can buy from the industrial B2B platform!their are many suppliers!

You definatley want to have one 5v signal that is on or off for turning the laser on or off. Usually the chinese power supplies have a 0-5v analog input for power. If you use pwm at high frequencies the analog input thinks its an analog signal and turns it into a 0-5v depending on duty cycle.

There is no real reasong to pwm the laser on adn off in pulse mode. That would be more for RF lasers and engraving.