Push fit parts on laser cutter

How do,

Would I be right in assuming the size of the cut from the laser to be around 1mm? for 3-6mm material(i appreciate this will vary with material thickness.

I would like to make some designs with a snug push fit, and to achieve this I guess i will need to take the cut width into account, has anyone any experience with this?


Hi Tim,

It depends on all sorts of things - type of material, thickness of material, speed of cut, how well the beam is in focus…

Typically less than 1mm though. Maybe 0.25mm?

You either need to do quite a lot of trial and error or design some springiness into your parts.

Hope this helps.

1 Like

Yeah, you have to experiment. There’s the added complication of the cut not being perfectly vertitcal. It’s a steep V shape, so you get a wider kerf at the top of the cut compared to the bottom.

Hi Rich, Tom,

Appreciate it is an open question, last time I made cuts (like if you cut a jigsaw out with just one line separating the pieces) it was a little floppy, so was just going to make one edge slightly smaller, will create a test board of various different sizes and see how it goes.

I will give .25, .4, .7 and see how what works,


The thing to keep in mind is while it’s trial and error, it’s also repeatable. Once you’ve done the work of figuring out the width that the laser cutter will make for specific settings with that material, all you need to do is note it down and you’re good for the next time, and the next time, and the next time…

1 Like

If your design is also dependant on the thickness of the material for the push fit bear in mind that thickness varies by 10% or more dependant on type and quality and size.
I’m going to start a millennium falcon model that requires adjustment of the templates depending on the measured thickness of the wood.

I do not know if this chart will be the same as the SLMS Laser cutter, but it is a good indicator.


Also, Please check with SLMS that you can use the materials listed below. I.e. i don’t know about paper.

Materials Thickness Average Kerf
Acrylic 1mm-3mm 0.18mm
Acrylic 5mm-8mm 0.21mm
Acrylic 10mm-15mm 0.3mm
Acrylic 20mm 0.32mm
HIPS, PETG, Styrene, 1mm-3mm 0.45mm
Birch plywood 0.8mm 0.08mm
Birch plywood 1.5mm 0.16mm
Birch plywood 3mm 0.2mm
Birch plywood 6mm 0.22mm
Birch plywood 12mm 0.3mm
MDF 3mm 0.16mm
MDF 6mm 0.2mm
MDF 12mm 0.28mm
Veneered MDF 6mm 0.17mm
Greyboard 1200microns 0.08mm
Greyboard 2400microns 0.12mm
Paper 90 – 350 gsm 0.08mm

Another tip, and i kinda fudged this together so i don’t know if there is another way. But when i was measuring up my AI file and creating all of the components i wanted to measure and design it as accurately as possible to the real world measurements. The problem being if you cut to these lines your model is half the kerf smaller than your AI.

However, depending on which verions of Illustrator your using, there is an “appearance menu”, showing a “Compound Path” tab that allows you to add a an “offset path” filter which gives you a mitre option. This means you can add an additional line to your design which takes into account the kerf setting.

Basically, you don’t have to rescale your design to take into account different kerfs.

I’ll see about sharing my AI file (though don’t print it, i got the design wrong :-p) But the bits that were correct had to be hammered into place, thats how tight the pieces were cut. So if you wanted to glue and or take into account material size changing (i.e. wood) then you will have to experiment with different kerf settings.

So if you use illustrator, then definitely try out the those settings.

Oh, Quick question, do we have a template file for designing with? and is it Adobe illustrator or another format?

Adobe illustrator 6 file using above mentioned path filter to account for kerf.

display_epaper.ai (295.2 KB)

NIce list.
Cast acrylic has a wider variation than extruded? (non-cast) acrylic I believe.
Also MDF is not allowed at SLMS (in the laser cutter at least)