Laser addon for Raw 1.5

Laser addon for Raw 1.5

We don’t sell lasers since they are a bit to dangerous but if you still want to add one, here is a guide.

When we started this project we were hoping for lasers that can cut through steel and thicker materials but we quickly realized that a system like that requires huge space and will cost a fortune. It’s still possible but not suitable for the hobby market. A weak system of 100W will only cut through wood and not metal. For metal you will need at least 2kw laser system. As an example of a 100W system you need a Co2 glass tube that is around 140cm long, imagine what’s required for a 2kw system.

So, the next best thing is diode lasers. Diode lasers are fun but very pricy if you buy it from a European company. They charge around 1000 Eur for a laser that can engrave and cut, maybe 4mm ply in 20 laps. I don’t think it’s worth the money if you just want to test this, so we came up with another solution, cheap Chinese laser’s for around 90Eur. Chinese lasers have a bad reputation but we managed to wire one correctly and had very nice results, even better that most of the pricy European ones that we have seen on YouTube. With this setup we can cut 4mm ply in 4 laps and cardboard etc. We can even control the strength of the beam by using the Spindle function in Mach 3.

Here is what we did, You can do this anyway you like and the guide is just a suggestion. We are not responsible for any damages to your equipment or health!

The laser is wired to a Raw1.5 with driver electronics and Mach3. We will try to add this to Arduino as well but I’m not sure we can control the strength of the beam.

The laser we use is a cheap Chinese laser from eBay, like this one: https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=15W+Laser+Head+Engraving+Module+TTL+450nm&_sacat=0

We attached the laser to an aluminum plate that we screwed to the Z-axis as seen in the picture.

As expected the laser came with no instructions at all so the first thing we needed to figure out is how to turn it on and off.

We found that we can turn it on and off in two places. Two of the on/off signals (on/off signal 2) is wired to the Z-axis and the other to the spindle port (on/off signal 1) that we set up. We tried to wire it only to the Spindle ports but it looks like the spindle function needs the Z-axis ports to function, let us explain.

The On /Off signal has to be sent in the exact cutting sequence or else it will start to burn to early or too late. We thought that we could just wire it to the Z-axis up and down sequence. When the z-axis moves up, turn the laser off and when the z-axis moves down, turn it on. The problem is that when the Z-axis is down the pulse from the drivers shuts down and the laser turns off again, meaning that the laser is only turned on when the Z-axis travels down and that won’t work. This is where the other On/Off signal is used. If we wire it to the Spindle port on the breakout board we can send a signal to the laser that the Z-axis has moved down, turn on the spindle/laser. This function can’t be used alone so we need all thre ports, two ports for the Z-axis (on/off signal 2) and one port for the spindle (on/off signal 1). If anyone can bypass the need of the Z-axis ports, please let us know.

Start by removing the Z-axis cables from the breakout board (P6 and P7 for Raw 1.5)
Wire the laser On/Off signal 1 cable to Red on P7
Wire the On/Off signal 2 wires, red on P17 and black on P16

 

In Mach3

Go to ports and pins. Activate the spindle and give it port 16 and 17

 

To be able to control the strength of the beam we need to change a few things.
Change the Pulley selection to the same value as the image below

Go back to ports and pins and to the Spindle setup tab and activate the motor control.

Go to Motor tuning and change the spindle values to this.

Change the Z motor to as high value as possible so that we get an instant response.

And we are done…

Don’t forget to save (config/save settings) or all values will be lost.

If you reset the machine and click on the button Spindle CW F5 the laser should turn on. The + and – will set the strength of the laser.

When you make your files in Vcarve for example then the tool spindle speed will tell the laser in what strength to burn. A low spindle speed means a low burn rate.

Also, don’t forget to set the safe Z in Vcarce or your other CAM software to as low as possible to get an instant on/off function.

We dont have any support for this but if we need to discuss this more we can do it over at Facebook.