I had a lot of response on this subject, and finally got around to doing a blog discussing the entire process.
So this is the machine that I use. It is a Haas SR-100 sheet router. This could be done with any CNC router/mill, really, this is just what I have.
This is the tooling that I use – V-Cutters from Hersaf. I did a lot of research into v-cutters, because I do a lot of engraving. I was told by several people that Hersaf is the best. I have a set of them and I have to agree – they are absolutely amazing. I’m told by Hersaf that they’ll even cut aluminum but I admit I’m scared! :) You don’t need a CNC machine to use these – they’re intended for cabinetry.
Ok so I cut the design into two pieces of wood. (Sorry I didn’T get photos of the cutting part; I was busy doing other things while it was cutting) The left is walnut, the right is maple. On the walnut I cut the design with a 90-degree cutter, basically as normal. On the maple, I cut the design (reversed) on the outside.
Close-up of the walnut.
Close-up of the maple.
You can see that they line up pretty well.
And then sit on top of each other perfectly.
I fill the walnut piece with glue. (Good ol’ Titebond III) As you can see, I am extremely liberal with the quantity of glue. It’s necessary. I’ve had pieces fail pretty hardcore because I missed a glue spot. Also rather than using a paintbrush I use a stick… years ago I was at a dollar store or something similar and they had bags of 1000 pairs of disposable chopsticks. Somehow I have more than a dozen of these bags, use them all the time,and it will still take me another ten years before I run out. But they’re perfect…
I don’t put any glue on the maple piece – it’s too hard to judge where all the glue is. I suppose I could use some kind of spray method, but this works, is pretty quick, not messy.
Clamp it all together. I try as much as possible to even out the pressure, but I also only put pressure on where the two pieces join. If I clamp on the edges of this design, it will pull the centre out and it won’t work. For this purpose, among others, I prefer to do designs that are fairly even distributed.
After it dried, I cut off the excess maple. (There was a lot – usually I try to pick a thin piece of wood, but eh.
There you go.
This particular one is kind of wonky… thanks to some weird parts on the initial design. When I do a normal v-carving of it, it looks very symmetrical, but it’s not at all. You can see that strongly here.
This is what it looks like when I do a normal carving of it…
also, I kind of messed up by removing too much material. But at that point -what can you do? Nothing.
It’s okay, somebody will love it I’m sure. :)