Keep Building

Novelty is overrated

Jan 31, 2015

Stampmaking Attempt

With the CNC Router fully operational, I turned my attention to stampmaking. The hope is that I will be able to draw custom stamps for my wife or others to help with various inkcraft projects.

After flailing around a bit with trying to use standard cam programs to make my stamp, I found F-engrave which can do magic. I have v-shaped engraving bits which can cut different sizes based on how deep the bit digs into the wood. With just the sharp point, you can score a thin line. With the whole bit in the wood, you can dig out a large channel. F-engrave understands this property and so can make a tool path to precisely cut out fine patterns.

There are four different cuts which need to be done. First a rough pass with an 3mm bit to clear away all the material not near a boundary. Second, a v-bit tracing of the outline which moves up and down to account for how thin the gaps must be. Third, a v-bit cleanup is done. Areas outside of the outline but too small for the roughing are cleaned away. And finally, the box around the design has to be cut out of the board. F-engrave can generate the first three tool paths and save them to different files. You need to use a standard CAM program to do the fourth one.

There are two gotchas here to be wary of. You want to scale the design before loading it into F-engrave. That will make it easier to ensure that the cut out tool path is correctly aligned to your engraved area. I screwed this up and ran a bit through my beautiful engraving. Also, make sure your art is already at the origin before importing it. If it is offset, the tool path F-engrave generates will be offset as well.

A stamp attempt

You can see my stamp attempt turned out pretty well before I accidentally carved across it later. The material is linoleum. I have read a few places that linoleum can work as a stampmaking material for CNC and you can find a few places that sell linoleum mounted to wood.

I decided to try a cheaper solution. I bought a linoleum tile from the local hardware store that had glue on the back. I just attached it to a small piece of wood and thought I was good to go. The real problem came when I tried to cut it out. The glue was not strong enough to hold a small section of linoleum on so when my cutout chipped off the linoleum around a stamp, the insides started shifting with the stress of cutting and I had to hit the emergency stop.

In order to make more progress, I will have to find a stronger adhesive to attach the tile to the wood. Or I will have to break down and buy pre-mounted stock online. So far I have learned a lot but have no stamps yet. Hopefully I will succeed soon.

Jan 27, 2015

Back Porch Factory

After a month of tinkering, upgrading, and building my router is truly useful. In this picture, it has just finished carving a pattern for a stamp from linoleum. It will be interesting to see what distributed fabrication will do to the economy over the coming years.

Working Shapeoko

Among the essential upgrades are homing switches that let me resume a job even after an emergency stop, a dust collection system with a dust shoe to save my lungs and sanity, and an upgraded spindle because the generic one that came with it failed.

Dec 20, 2014

Woodcraft For Idiots

The box contained a Shapeoko 2 which is a CNC router. This will let me cut out many kinds of wooden or even plastic parts and designs with a computer. I am not that great at classic woodworking skills like drilling straight holes and making sure things are square. This machine will let me do all of that by simply drawing them out at my computer which is considerably easier. The default kit will have a work area of 12"x12" or so. This is too small to cut furniture or other large projects, but there are still a lot of things I can make. Later on, I can upgrade it to do bigger pieces.

The box came absolutely stuffed with screws and plates and pieces:

Shapeoko in box form

Here are some of the pieces laid out on the new workbench:

Parts for the CNC router

The first big piece to be assembled was the z-axis. Then I rolled it onto the x-axis rails. The tower in the middle is built around a threaded rod which rotates to move it up and down. The tool itself is attached to it.

Assembled Gantry

Here is a closer view of the main gantry. The x-axis is belt-driven and will move the tower left and right along the rails.

Close up of z-axis

And here is the frame completely assembled. The x-axis assembly is mounted on two rails which form the y-axis. These are also belt driven and move the whole x-axis back and forth.

Completed CNC router frame

All of this is electronically controlled by an Arduino board wired to stepper motors via a shield. My current status is that everything is wired up, belts are installed, and I can use my laptop to control it moving it slowly around. But I am running into issues where the z-axis is binding up and not turning with the stepper motor sometimes.

The working machine is so close, but so far away...