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E1 3W Laser with 3mm MDF

After tinkering for a full week, I finally got a chance to cut 3mm MDF. It did not go as well as I’d hoped.

I have a 3w, and made about 16ish passes on it, 95% power at 350mm/min and set it to 2.2a. Any suggestions? I was only able to cut about 1/16" deep.

Go back to tuning the laser? Has anyone had a good tip to do this? I used a piece of paper, ran the 1600ms/min at 100% power and had some skipping, but it was almost completely through the paper.

Thanks for any input!


A properly focused 3 watt laser should be able to fully cut through plain white copy paper at between 1800-2000mm/min. If you are not getting this, then you should revise the focus. It seems you are not far off, but with dense materials such as MDF, every ounce of power helps.

To tune your focus, try creating a simple shape, like a circle. Set your feed-rate to 1800mm/min and power to 100%. Use a sheet of plain white copy paper.

Then perform a cut. If the paper does not cut through, adjust the lens a small amount (1/16 turn) in one direction.

Repeat the cut. If it got better, adjust the lens again in the same direction. If it got worse, turn the lens 1/8 turn in the opposite direction.

Repeat the cut. 

Continue this until to close in on the perfect setting.

It may take a little time, but once this is done, you shouldn’t have to do it again, unless you move your lens.


Hope that helps.


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I have cut 3mm MDF but I use the 4w unit.

My settings still need 6-7 passes at 100% pwr using 350mm/min.  Never tried with the 3w unit tbh.

I use the 4w laser, but can’t seem to cut through 3mm mdf. 1mm cardboard is working (10 passes 50mm/s 100%). I already tried to refocus, but it didn’t improve.

Do you need to boost the power on the arduino?

With the 4w unit you are safe to switch all the current switches to on as my understanding is that this will not damage the unit, I spent about 2 hours focusing on a scrap bit of material to get it right.  The type of MDF needs to be right to, I bought some laser MDF from eBay.

I notice you are using mm /s for wood you should be using mm/min :wink: mm/s for wood on this type of laser I’m sure would take 100s of passes, I may try it some time as a test!

very interested to hear about the new units being tested!

Hi Daniel, thx for the feedback! Could be my mistake, I was just referencing from memory. But will check tomorrow. I just ordered MDF from the Wood supplier, so that could be the problem too apparently. Getting a bit frustrated with it tbh. :wink:

No worries Zologie :slight_smile:

Stick with it! It does pay off, are you resting material directly onto the metal base plate? I get much better cuts by raising materials off the bed, commercial cutters have a honeycomb underneath so my Diy way is to use bolts blu tacked at each of the corners to give the wood about 4mm clearance from the base.

i found somewhere between 350-400mm/min with 6 - 8 passes seems to work for me! I also add one final cut at a much slower speed just to finish it off :slight_smile:

keep us posted!

For 4w laser 80g paper 1 pass = 2000-2300mm /min  ok focus ,


I cut 3mm MDF with a 3W laser. 300mm/min 100% 6 passes.   Reinforcing Domenic’s post. The absolute key is spending some time getting the optimum focus.




Cutting 2.75mm MDF cover sheet (nominal 3mm)

4 watt 100% 300mm/min 3 passes.

It may be getting reverse air assist from my vacuum table. I replaced the top with a woven stainless steel mesh.


Thanks for all the tips. As it turns out, I was running “per second” instead of per minute. Stupid me. :slight_smile: I did a testrun at 6x 350mm/min / 100% at default power settings and got much better results. Not cut through yet but about 3/5. Way better than before. I’ll try to up the passes and lower the speed, maybe boost the power of the laser on the main board.

Thanks again!