Inlay question


#1

So I want to do an inlay, but I don’t know if I need to compensate for kerf. I’m thinking I’ll be inlaying :proofgrade: medium acrylic and :proofgrade: veneer onto :proofgrade: medium or thick wood. My question is, do I take the exact same object, engrave it into the wood, then cut it out of the acrylic and veneer without resizing anything? Or do I need to create a kerf buffer?

Thanks!


#2

How snug do you want it?

This is where you experiment and then tell US!


#3

Experiment with the actual materials. (Even Proofgrade.)

Acrylic into acrylic is very unforgiving. You absolutely have to have it spot on if you want it to fit.

Acrylic inset into wood, or veneer inset into wood is not going to be as much of a problem. The wood will yield a little bit and you can force it in. If you do not kerf adjust, you will probably have a slightly tight fit for the woods, because focusing on the surface gives a very narrow bottom cut, and a wider top cut. (What the defaults do.)


#4

Heh! No disagreement on that! Just figure I’m not the first, so I’d learn from a master.

Your post makes perfect sense to me!


#5

I have an idea I want to explore, since the beam diverges below the focal point, I want to see the result of flipping the piece to be inlayed and cut it from the back to see how the two edge angles fit.

I recall that @dannyc at Glowforge posted an excellent tutorial on kerf compensation a while back… Here.

Thanks again Danny!


#6

I’ve thought of the same thing. I would imagine that they would fit pretty well


#7

I’m pretty sure @marmak3261 did that for his scrabble board.


#8

Why not focus it half way through the cut to aim to get the top and bottom kerfs equal?


#9

I did lots of experiments on different hardwoods and solid soft wood like pine and found that it was very challenging to get the relief engraved for the inset with a smooth and consistent bottom. The Proofgrade plywood works well since it is consistent. You could even do Draftboard and skin it with veneer and acrylic.

Acrylic seems to have a smaller kerf for me and as @jules says is unyielding and harder to trim once it is cut. The kerf allowance for cutting veneer is not negligible. I got lots of good advice in the topic that @PrintToLaser referenced, especially from @jules and @dannyc.

Here is my set of letter tiles. It will give you an idea of how the cut line is sized in relation to the base engrave. I made it extremely tight and since it is wood, it has some give. I also sanded smooth and then sprayed lacquer for the final surface.

UploadTiles


#10

They did, I was just in experimental mode at the time (have been since
I was granted the use of this machine) and was pushing the envelope.


#11

It doesn’t really work like that, I’ve noticed that the kerf is always a ‘V’ shape from the top down. Given that we focus the laser beam on the top of the sheet you would expect it to be the opposite. I guess the top is vaporised the most and by the time it gets to the bottom it’s only being vaporised for the smallest amount of time.


#12

Thanks for that Understanding! :sunglasses: