Laser added to my CNC machine

Leo Voisine

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NOT that I will do this any time soon, but I am intrigued by the thought of adding Laser to my CNC machine.

I see it being done or played with from time to time.

I think Darren did something like this.

Any thoughts on the subject?
 
If you're running Mach3, you'll have to add an dac circuit to adjust the laser's intensity, which is the problem I ran into. It basically takes the PWM values and converts them from a 1 to 100 intensity value for the laser. The issue is that Mach3 was pausing (even with dwell set to 0) at any change that normally would be used for the PWM and what should have been gray scale art, turned into burnt toast. ;) I want to say that I passed an M10 & M11 to compensate for the pauses, but there was still something with it adjusting the intensity that required the dac.

The laser kit I got was the 2.0w here: https://jtechphotonics.com/?product_cat=laser-and-driver-combo-kits

I think Brent got the 2.8w, but will let him chime in.

Here is the dac board they have now, which they didn't earlier: https://jtechphotonics.com/?product=dacpwm-converter-board

I think adding a laser would be a good idea for doing labeling and adding alignment marks. You wouldn't necessarily need anything over a 500mw laser to do that , but the 2w will get the job done faster.
 
Just done it with mine.

Got an LCheapo - http://robots-everywhere.com/re_site/purchase/l-cheapo/. They call it a cutter but for me its more about engraving/marking for which it works perfectly.

Made up a very simple doohicky to enable me to hold it in the Kress spindle (43mm) mount. Used an old laptop power supply to get 230V down to 12 V.

Spent a day messing around with postprocessor files in Vectric VCarve to eliminate the small delays that are inherent in Mach 3 when you turn the spindle on and off.

Got it all working and earning nmoney within 3 days of it arriving in the post.

If you get there and are using vcarve let me know and I'll share my Postprocessor files so you can see whats worked for me.
 
I think Darren is building a separate machine.

Knowing what little I do from the machine at my lab, there is more to it than just changing out the working end of he Z-axis and different software. For starters, a different bed would have to be used (or plan on starting fires!). And every commercial machine I've seen has shrouds all around and a venting system. The fumes can be toxic. In addition there is a shaded viewing glass, like a welder's helmet, through which you can watch the action.

I really think the only thing they have in common with a CNC is the xyz movement. But I am sure a lot depends on just what you wanted to do with it. Used machines are available and even smaller new ones are not prohibitively expensive. Not sure a DIY solution would be cost effective.

Will be interesting to see what others say.
 
If you get there and are using vcarve let me know and I'll share my Postprocessor files so you can see whats worked for me.

If you wouldn't mind sharing with me also, I've got vcarve and plan to use it for some of the projects I have for the new laser bed...Thanks. :wave:

So are you cutting with yours, if so, what materials?
 
My comments need to be interpreted in the light of the way Im using the machine.

What Carol says applies to proper industrial grade cutting set ups but mine is intended to do nothing more than surface marking on timber.

It does that well.

I use safety glasses (supplied with the laser) or a shroud to avoid the "arc eye" problem.

I use a workshop vac located near the burn point to extract the smoke and feed it through the hepa filter in the machine before dissipating it in the air. This is smoke so you don't need much airflow to change its path.

I have no plans to cut plastics so avoid the more dangerous gasses that get produced there.

Darren - I don't really plan on using it to cut but ineviably my Blofeld strain means that I have tried it. And it can cut. I've tried it on corrugated card about 3mm (1/8") thick and at a cut speed of 600mm/min (about 26"/min) it took 8 passes to burn through. So while cutting is technically possible Sean Connery isn't gonna need reinforced trousers any time soon. - I'm gonna DM you for an email address so I can send the PostProcessor file with some explanatory notes. I still think there may be a couple of bits where it can be further tidied but it gives a pretty clean engrave on my setup.

Basically I wanted to be able to laser mark wooden objects and my £150 setup works where I was never gonna spend thousands.
 
This is what I am doing - I think that I can probably reduce the slight overburn at the start point but my customer, who is very happy with the result, wanted to take delivery rather than let me fanny around. This image is probably bigger on your screen than in real life but the real life appearance is absolutely fine.
 

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This is what I am doing - I think that I can probably reduce the slight overburn at the start point but my customer, who is very happy with the result, wanted to take delivery rather than let me fanny around. This image is probably bigger on your screen than in real life but the real life appearance is absolutely fine.
View attachment 98353

That looks good! I was able to produce line drawing stuff like that on mine and mach 3, but not gray scale stuff. I doubt I do any cutting with it either, but never know what I'll get into. ;)
 
I haven't started to think about greyscale. The LCheapo has a PWM control option but when I started looking at the Mach3 end of that option my ears started to bleed and my customer was pressing for time. I have it somewhere on a list!
 
i'm going to be adding a laser to my cnc machine as part of the overall upgrade (size-wise that is). one of our newly minted 3d printing bretheren have done up the new brackets for me, and should be here soon.
 
i'm going to be adding a laser to my cnc machine as part of the overall upgrade (size-wise that is). one of our newly minted 3d printing bretheren have done up the new brackets for me, and should be here soon.
Any day now! Whoops, I'm still looking at them on my desk. I'll find something to put them in the mail!
 
This is getting interesting. Clearly, intended use has lots to do with making this decision. The line seems to be divided between engraving type activities and cutting out activities.

Which translates into power (amperage).

Which translates into $$$.

Now my brain has some muddling to do as well.
 
This is getting interesting. Clearly, intended use has lots to do with making this decision. The line seems to be divided between engraving type activities and cutting out activities.

Which translates into power (amperage).

Which translates into $$$.

...

Couldn't have said it any better. My needs and ambitions are modest and with this option the cost matches them. The job I am doing with this will pay for the cost of setting up several times over on its first run. Now all I need is to get lots more jobs that I can say that about!
 
Yes interesting.

I think I would like to be able to cut 1/8 plywood, plus engraving a multiple on materials.

My goals might be too lofty, but hey, gotta start somewhere.

In 2004 I was seriously considering an Epilog lazer machine.

I know I would need to retrofit my machine but that is to be expected.

I don't want to "convert" my machine. I want it to dual purpose.
 
Yes interesting.

I think I would like to be able to cut 1/8 plywood, plus engraving a multiple on materials.

My goals might be too lofty, but hey, gotta start somewhere.

In 2004 I was seriously considering an Epilog lazer machine.

I know I would need to retrofit my machine but that is to be expected.

I don't want to "convert" my machine. I want it to dual purpose.

To cut using the laser you'll have to looks at a co2 laser (probably 20w or bigger) for any efficiency on 1/8" ply, but for light engraving the 2w - 5w would work fine. Honestly for any kind of production work, you may want different machines as each will be running their processes at their own speeds.
 
The laser at the lab is 30w, I think. It can cut (barely) 1/4" acrylic (but it does a beautiful job on that. Even impressed Larry!). But it cannot cut 1/4" plywood. Lots of burning and starting of fires, so it is banned. It can cut 1/8" plywood without too much burning. So that should give you some idea of what you are up against.

For cutting out operations, the CNC ought to suffice.

Like Darren. Separate machines for that task.
 
I don't want to "convert" my machine. I want it to dual purpose.

that's my plan too leo. the jtechphonics people's shapeoko 2 upgrade involves the removal of the spindle, in order to add the laser. i didn't want to go through that hassle each time i wanted to use one or the other, and designed a replacement bracket, which brent so kindly printed out for me, and keep both the spindle and the laser.
 
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