First part made!

Just here to share the first part that I made. Lots of learning experiences. I ended up piecing together multiple operations, fixing errors as I went. Since I didn’t run dual endstops, the ops didn’t line up perfectly and I had to do lots of cleanup. Instead of using an endstop, I used a spacer so that I could just move the motors until they hit the spacer. It kinda worked, but I am going to need the endstops if I want things to be square and fit up at 90°. There was also a bunch of fuzz from the upcutting bit. Should I use a higher feed per tooth to prevent this?

The cuts I’m doing definitely would be better with a laser cutter. How good are the MPCNC’s with laser cutters?



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Can you take a pic from your tool bit?
What spindle speeds and what feed you used?

They look like a great starting point and I’m sure you can get even better results. Did you run a finishing pass? It can be part of the same gcode file so no need to re-home or change bits. In ply you can normally run a fast finishing pass, maybe just 0.3mm perhaps at full depth. Makes a lot of difference.

I think the method of using spacer blocks is good. So long as the machine is square it doesn’t really matter for many operations if you use end-stops or not, they are nice to have though.

I have a laser on my MPCNC and it works well. The only drawback is that you are limited on the speed you can run it. I have a 5W and a 20W, so my MPCNC is fast enough. With a higher power laser you would be limited.

Here’s a pick of the bit and my feeds & speeds:
Spindle speed is default DW660 speed (which I think is 30000 rpm)
Surface speed: 300mm/min
Feed per tooth: 0.016 mm
Cutting feedrate: 480mm/min
Maximum stepdown: 2.5mm


The bit is a 1/8", single-flute upcutting bit.

I thought I had done a finishing pass, but apparently I forgot to do it in the pockets! I will definitely add a 0.3mm stepover finishing pass on the next run.

I liked using the spacer blocks. It felt simple and easy to set up. I do want to figure out a way to make my squaring up more consistent though so I might affix some to the printer itself and see how that goes

Good to know! I see that 40W is recommended for cutting wood, so are you suggesting that the MPCNC can’t go fast enough to keep up with a 40W laser?
With the 20W laser, what major equipment do you need other than a diode/heatsink, a driver board and power supply, and a smoke fan? How much did that all cost you? I see diodes for $35 on Aliexpress but that seems like it’s only a fraction of the cost.

That bit has a slightly rough cutting edge. There are also smooth-edged bits. But that is not the reason. I think you could raise cutting feedrate.

The MPCNC would work fine on the part you cut out in the photo.
For things with fine detail, you would have to turn down the power quite a bit so you don’t burn through the material.
The MPCNC has a lot of mass at the core. I can run mine around 2000-2500 mm/minute.
I bought the LaserTree 20W for $230. I have a 24V power supply with 3 outputs, so I could use that to power my laser. I connected the PWN to my Jackpot directly.
On Aliexpress be sure and check the Optical Output Power for the laser. They don’t show that normally.
This is the Aliexpress listing for my laser:
https://www.aliexpress.us/item/3256802976882028.html?spm=a2g0o.productlist.main.3.5024V8VAV8VAGR&algo_pvid=766413c3-b0e0-4d45-9bac-909ddf64cde0&algo_exp_id=766413c3-b0e0-4d45-9bac-909ddf64cde0-1&pdp_npi=4%40dis!USD!85.80!26.32!!!85.80!26.32!%402103011017192530594623358ea686!12000029813375618!sea!US!0!AB&curPageLogUid=ILsjBncj0faD&utparam-url=scene%3Asearch|query_from%3A#nav-description

This is the LaserTree listing:

BIG DIFFERENCE. Aliexpress doesn’t use optical power for their wattage rating.

And here is the 40W Optical Power module:

It can run a lot faster than this is you set up your microstepping to a lower value and use larger pulleys. I often run mine at speeds upwards 200mm/s (12 000mm/min). I’m using 1/16 microstepping and steppers are wired in series.
Acceleration is a little more tricky but from my experience the standard MPCNC stills runs ok up to 3000mms-2

Not saying it would be wise to run the laser at that kind of speeds of course, but my point is that you still have some comfortable margin for increasing it a little.

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looking at the mill, it seems to me it is not sharp on the edge and the tip seems to be blue. Is this the one U used?

I got bits that looked like this from Amazon. About 5€ for 10 pcs. or so. I didn’t realize it until I got some better ones, but they were seriously dull. Like Eetu ans Frits said, yours looks to be dull as well.

WOW, I have only run mine as fast as 3000mm/min. It blows my mind that you have run yours at 12,000mm/min.

I mean there is difference between these two bits. Cut made by Left need more sanding after cut than right.

Congratulations!! Great things to come!

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@ebbels What feed per tooth do you use?
@Frits Yes, this is the bit I used. It was that color before I started. I have another bit that I can try though.
@tapani I would believe it. These are bits from Aliexpress.

@Britt Thank you for the valuable information on the laser cutters!

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I don’t have mpcnc (I have lr3) so I don’t have specific feed and speed for you. I also think that there is no speed and feed ultimate value which works for everyone. Each v1 cnc is unique. So each user has to find their own best values.

I use fz 0.09-0.1mm/tooth atm.

Can U lower your rpm ?

I’m sure you will find better values and maybe better toolbit