Offset and inlay

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Inlays and Offsets

Getting in a little bit deeper with Inkscape and laser cutter this week! Over the weekend I got considering potential future projects I might be doing, and while thinking about those I also wondered how you could efficiently combine two (or more) different (coloured) materials.

And here we get to inlaying and offsetting. Due to the slight amount of material getting cut/burned when using the laser cutter, you can't do a split object and call it day. They will fit into each other, but the fit won't be precise. By offsetting, you can create shapes that fit into each other perfectly.

I first started out with basic square shapes and cardboard. First test I clearly didn't get it. I did just what I first described. Two poorly fitting shapes. The next try was already better and I managed to actually get a decent fit.

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With the line thickness of 0,01 the offset with 0,2 mm was good. Woohoo!

Next I proceeded to test it out with plexiglass. The material behaves a bit differently, and at first I did a test with three different offsets. One at 0,1 mm, second at 0,2 mm and third at 0,4 mm. The third one was actually the precise fit so I jotted that down on my notebook for future use.

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Finally I started to try this with more irregular shapes, aka letters. First try was actually sort of a success as far as fit went, but it's also important to remember there is a difference between millimeters and centimeters.

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After this you could clearly see it was Monday. Many failed attempts, several where I didn't even successfully get to the actual cutting phase because I just couldn't get Inkscape to do what I wanted. But in the end I prevailed!

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Witness the perfectly fitting blue/red example on the middle! (and the completely green one to the left, but that's a bit drab.)

If I had failed a few more times I could've built an optometrist test board.