Laser thickness


I’ve been trying to make some joints with my GF and they are always way too loose - this is because of the width of the cut. How much should I be subtracting from my shapes to make them interlock.

I’m working with non Proofgrade 1/8" MDF - using the medium fibreboard settings.

Or… does anybody have a file I can take a look at that works?


Do a search for “kerf” here. There is loads of information.


Here’s a little box I made to hold #20 biscuits for my biscuit joiner. It fits together nicely. I apologize I can’t remember what I did for kerf and all that, but you asked for a file, and I do know this one works. I believe I made it using the Tabbed Box Maker plugin for Inkscape found at Github.



In the 1/8" wood/plywood I usually compensate .007" for the kerf. Look at the how tos in the Tips and Tricks for some robust discussion on what to add where in your design.


Thanks! I added 0.4mm to my tabs (0.2/side) which made the difference.


It’s not so much the “width” of the beam, as it is the amount of material removed (vaporized) by it - so it varies by material, cut speed, etc. As suggested, there’s lots of info here, but cutting a small box out of the material, then measuring the dimensions of the inside of the hole, and outside of the removed piece, gives you a (2x) idea of the kerf for those settings.


Take a look at this great post by @Jules. I used it as a starting point for doing some engraves this past week and it really helped me a ton. An excellent starting point for getting things perfectly snug.

Awesome tips from @Jules