New Bowls

Some hand-turned and CNC machined bowls.

Redwood burl. About 11"

12" cherry dyed black

5.5" mystery wood, dyed green

5.5" mystery wood, dyed black

Walnut spiral. 6.5", CNC

5" walnut, CNC

10" red cherry

Wind wave sculpture

I'm working with friend on a wind-powered kinetic sculpture. This is a half-scale model out of wood to verify the mechanics.

And here's a road test with the sail attached. I'm calling out engine RPM to estimate speed because the speedometer is not very accurate at low speeds. 1900 rpm equals somewhere between 9 & 10 mph.

This test provided great information about how it behaves in the wind. We're going to try less offset on the crankarm and reduce the amount of travel in the rods. Oh, and make it stronger, too.

Mobius carvings

I've been salvaging old douglas fir beams from building demolitions for carving. Douglas fir takes on this wonderful texture when it gets old: it becomes more consistent, less difference in hardness between the rings, and it's easier to carve across the grain than new fir. With a sharp chisel, you can make big, bold cuts. Very satisfying. These two mobius carvings were early projects from reclaimed fir.

 

First attempt -- about 6" 

It was a bit tough to visualize how the surfaces wrapped around the shape, so I started with models. First, I made a donut from modeling clay, drew the corners as they wrapped around the shape, and then scraped a flat plane between the lines. Next, I built a series of models in Sketchup -- a bit laborious, but it helped a lot to see what needed to be done.

To make the small mobius, I started with a donut with a round cross-section, traced the corners as they wrapped around the part and carved a flat surface between the lines, being careful to measure the flats  radially. The larger one was harder: I made it in two halves, doweled together. The majority of the shaping was performed on each half separately, then the finish work was done with the part glued together.

Router lathe: Big bolt

big bolt and nut

The first finished part to come off the router lathe. I figured when building a machine to cut big spirals and threads, what better test than to make a great big bolt and a nut to fit on it.

The entire bolt is about 17" long and 3.5" in diameter. The thread pitch is 2.5 threads per inch. The head and the nut are about 6.5" in diameter and the nut is 2.75" thick. 

The threads work

The original idea that started this project was to adapt a wood lathe to cut great big wood threads, both internal and external. And here they are. In that regard, I guess I'm finished. However, this project has presented a bunch of new exciting possibilities to explore.

With wrench and screwdriver for scale.

(side note: the wood looks like it has been stained, but it's not. This is its color with neutral Watco oil. The wood was some salvaged asian oak of some kind from shipping containers at the port, and came out much darker than I expected.)

Here's the code: Final Arduino Code

< Internal threads  -- New lead screw >