Need help with pwm control of a laser
I am new to Mach3 and CNC machining and recognize that there is a learning curve.
I have a DIY CNC that is NOT using the spindle control and everything is working fine. I am now adding a diode laser. I have looked at all of the youtube videos on setting up Mach3, but think I need some different hardware. Answers to the following questions should point me in the right direction.
- Every youtube video uses a breakout board with a spindle relay. My board does not have one. Do I need a different board?
- The breakout boards with the relays seem to need a 12-24V input in addition to the 5V. My board does not have this. Do I need a different board?
- Assuming that I need a new board, does the TTL input to the laser controller get connected to the relay or the TTL ports on the board? I can manually power up the laser, but what Mach3 to turn the beam on and off.
- When I get this working, can I manually turn on the beam within Mach3 and adjust the power down for focusing
Any help would be appreciated
Re: Need help with pwm control of a laser
I'm to a similar place as you and found these threads helpful. The first 2 are from CNCZone. The 3rd one I picked up somewhere else.
Need help with laser driver and TTL signal
Need help with PWM laser control in Mach3
Adding Laser Engraver to CNC Router and Activating in Mach3 – hackingismakingisengineering
My intention is to use a very cheap Chinese bob DB255 1205 as I have one laying around and use the mach3 command M4 for my laser power to turn on, ( I don't use reverse spindle), M5 off and the S command ( spindle speed) to control the ttl firing, S0 for off S1+ on. My particular laser does not have variable power intensity, but I will see what happens when I vary the voltage input power to the laser.
Re: Need help with pwm control of a laser
Quote:
Originally Posted by
chopper13
This type? I use this for my mill and works great.
https://www.youtube.com/watch?v=auXuJQI3tO4
5v is for the bottom row of connectors for axis motion. You need seperate 12-24v power in the right to operate the spindle controls (right) and limit/ estop functions (left).
Re: Need help with pwm control of a laser
Yes that is what I have spare and intend using on my second router. This router that will have both spindle and laser fitted, with this bob, using M3 for spindle on and M4 for laser power on, M5 both off. As I don't use spindle speed and prefer to adjust this manually I can use the Mach3 spindle speed to switch the ttl for the laser. At least that is what I understand can be done. I may look at using a switch, micro or proximity, on the z axis to switch the ttl on and off. If this is possible quickly, then it would be alot easier for programming. Below Z- ttl on Z+ ttl off. That way I can use the Z- for successive cuts and Z+ for transition to alternative positions.
Re: Need help with pwm control of a laser
I haven't set up my mill spindle to it yet, not confident messing with the wiring atm.
I'm using X,Y,Z as you normally would and axis A is switching a relay on/off for my flood coolant M8,M9.
Leaves the on board relay free still for when I tackle the spindle. Works well and seems pretty adaptable.
Re: Need help with pwm control of a laser
I have just replaced my number one router controller with a new TB6600 bob and ESS Warp 9 and wired it all up with the spindle and VFD. I had to sort through the differing advice on this forum and settled on mactec54's advice and instructions. Worked first time and I have confidence that it is all wired up safely and properly.
The old black box controller I was using has a bob in it that no one has been able to recognise or name. The supplier has not been forth coming with information on it either.
So this is currently running the no 2 router.
Having to put a S command on every Z axis movement is going to be a pain in the butt, so will look to see how else the switching can be accomplished.
I have 3 options;
The TB6600 4 axis bob has 2 relays, I have a spare, and the 3 axis bob has 3 relays, but no pwm out, just 10v on or off. However this could activate a relay with 5v for the TTL to trigger.
The DB25-1205
XHC MK4 usb 4 axis bob and drivers. Been sitting in the draw for some time.
I'll play with the DB25 first, I want to be able to run both spindle and or laser off the same setup without having to switch things around.
Re: Need help with pwm control of a laser
Quote:
Originally Posted by
chopper13
I have just replaced my number one router controller with a new TB6600 bob and ESS Warp 9 and wired it all up with the spindle and VFD. I had to sort through the differing advice on this forum and settled on mactec54's advice and instructions. Worked first time and I have confidence that it is all wired up safely and properly.
The old black box controller I was using has a bob in it that no one has been able to recognise or name. The supplier has not been forth coming with information on it either.
So this is currently running the no 2 router.
Having to put a S command on every Z axis movement is going to be a pain in the butt, so will look to see how else the switching can be accomplished.
I have 3 options;
The TB6600 4 axis bob has 2 relays, I have a spare, and the 3 axis bob has 3 relays, but no pwm out, just 10v on or off. However this could activate a relay with 5v for the TTL to trigger.
The DB25-1205
XHC MK4 usb 4 axis bob and drivers. Been sitting in the draw for some time.
I'll play with the DB25 first, I want to be able to run both spindle and or laser off the same setup without having to switch things around.
For <£10 I'd just attach one of those DB25 boards shown earlier if you have not used port 3 on the ess. Use it just for spindle, and a relay from one of the axis ports for the laser perhaps.
I don't know anything about lasers. Does that need some kind of voltage control too?
I'm saving for an ess too. I plan to use a decent bob for all the axis control on port1 and the rest (as/when I need it) using the cheap DB25's on ports 2&3. That's if it works like that.
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Re: Need help with pwm control of a laser
That would be a way to go with the ESS if that is how the 3 ports work, but it is on my number 1 router, 6040.
The laser is going onto number 2 router 3040. This router is my test bed for anything I want to try out. While the number 1 router is going well I don't want to stuff it up while I'm playing around!
My laser has a fixed voltage and is fired by the TTL. There is no PWM feature. But it can run continuously for 8 hours. It is an 18 watt ( most likely input current, not output) figuring around around 8 watt output. I bought this one as the feed back suggested the lenses are of good quality, were as the 20 watts I had looked at the lenses were not so good, reportedly.
At the moment I just sifting through information until I'm satisfied with the way I will go for the laser.
This is another option for a parallel port breakout board. I have seen one of these used to pull off the pins to run a laser.
