This beautiful piece of wood is just over 2" thick. I don't know what the name of the wood is but I bought it at a botanical garden South of Puerta Vallarta, Mexico.
Even from the first time I saw this wood I was really drawn to it. I don't remember when I first thought of it as a clock "plate" but it wasn't long after.
It was about this time the my favourite gear design program Gearotic via its add-on piece Vexx, made it possible to design a Club Footed escapement.
This excapement has some really appealing characteristics for the wood crafter. Basically that is that is can be cut from ply with a reasonable assurance of success - no really fine "points" to break off and ruin the wheel, and the same is true of the pallets.
The wheel locations were not taken from the Gearotic program but rather by putting matching gear sets on the depthing guage and then "locating" a desireable location on the block of wood.
The arbors on the depthing guage were ground to a point and were used as a center punch directly on the clock.
This shows the running gears all in place with the one exception of the Great Wheel on the right using a 9 leaf pinion driving the train instead of the 45 tooth component of the wheel. This meant that the clock running train could be tested with much less weight.
The actual weight I used for "proof of concept" was 8 ounces
The great wheel now drives a pinion on the "final" version of the running train. The great wheel now turns once per hour.
The pendulum is a one second pendulum
This is the on the wall experience.
The really wide pendulum probably detracts from the accuracy of the clock but I had always wanted to build a "big" swing.
The swing is accomplished by setting the lock to 1.5 degrees.
Although the clock mechanism was neat , I was disappointed that the exotic wood it was mounted on was almost invisible.
I decided to try and recut the gears in Acrylic.
The big problem with Acrylic is the cut material adheres to the bit and soon starts to melt the surface near the cut and although it doesn't "ruin" the piece it does disfigure the surface near the cut.
My CNC machine runs the cutting head at a fixed speed (20,000 RPM) and I found that the milling speed of 20 inches per minute worked the best.
The solution to a nice clean cut turned out to be to make a small puddle of oil and ensure the cutter always cut in that pool. The end result was that the build up on the bit only took place on the initial cycle, I could then stop and clean the bit and the rest of the cut was clean and the finished product really nice.
The gear train is now nice and transparent and the wood mounting plate is clearly visible.
The time train is not shown in this picture but is a Aaron Dodd daisy mechanism. Also the acrylic pallets and pendulum have yet to be mounted.
All in all I have achieved what I wanted.