Using a Shapeoko 3 CNC machine for a 24-tooth escape wheel
We didn't know anything about CNC machines, but have been quite curious about them for a long time. So,
being tempted by their "black friday Christmas special," we used this clock project as an excuse
to buy a Shapeoko3, by Carbide3D.
After watching a bunch of this guy's videos, we got to work.
We tried to hand cut a 24-tooth escape wheel a few times, and just couldn't get one to work. So, owing to the rapid prototyping now possible
with a CNC, we gave it a try. We drew up a new wheel in AutoCAD as shown here:
Here's the .dxf file for it. Remember
to scale it up to 3.5". Here it is being cut on the Shapeoko CNC machine:
When done, we sanded it lightly and popped it into our basic clock core, and off it went:
Note how much more gentle the escapement is with 24 teeth, as the escape wheel can't travel as far the 12-tooth one does between
pallet engagements. We also had to reverse the left screw in the pallet (it's upside down in the 12-tooth design), and sand the end down
a little bit.
We'll note that, like the escape wheel, we've worked up a 3D printer/CNC route to the pallet too.
Thoughts on the CNC machine?
The CNC machine was great! We went from a blank AutoCAD screen to a ticking escapement in about an hour!
As far as the Shapeoko goes, we highly recommend it! It's great for beginners to CNC (like us), and is
a huge upgrade to what we can make (and how it'll turn out). We've already made clock gears, a couple of signs, some
helmholtz coils, and a few gifts. We love it, and find it much more useful than a 3D printer.