Steve Hobley's Fabrications Using the blackToe CNC Machine
Steve Hobley'sFritz Lang's Theremin Stand:
Theremin: A musical instrument that functions without any physical contact with
the actual musical instrument. I've always though this is the perfect instrument
for conductors! Don't worry, this is not a theremin webpage, but I want to show
you a theremin stand that was fabricated by Steve Hobley using his
blackToe CNC machine. Steve stated that the use of eliptical shapes really
shows-off the benefit of using a CNC machine. It's true, especially with the well
formed slight curves and curvy forms spanning the legs. It would be interesting
to know if the form itself has some influence on the musical note.
Check it out on his site.
My favorite part of the design is actually on the back, where the coils are held
by two circular caps and a collar in-between. The lower front, where the speaker
is mounted has a nice cohesive look with its eliptical design.
Steve elected to create the general form with the CNC machine and smooth the hard
edges by hand. This is quite an appropriate use of the CNC machine. Let the machine
do the difficult part of the fabrication, but still allowing the human to get their
hands dirty.
Steve's Clock:
Steve has updated his clock. The clock now has a face, and the gears are painted
to easily distinguish the major time functions. But the most important detail in
this update is Steve's journey into tool changes during the clock face fabrication.
On
his blog (Carving the Clock Face), he details the process he used to change
the end mills to achieve his desired results.
Wall clocks
that exhibit the exposed gearing, pendulum fabricated out of wood, is a great showcase
for clock functions and provides a great example for what CNC Machines can do well.
Steve Hobley, using the blackToe
CNC Machine kit, fabricated all of the gears for
this clock.
Steve Hobley always impresses me with his creative projects and this clock is an
example of how he uses creativity in his mechanical design and striving for efficiency
with less frequent pulse to the coil to move the pendulum.
Mechanically, he is using a 15 tooth ratchet, componunded with a 15 tooth gear that
turns a 60 tooth gear. This gear turns another 60 tooth gear that is connected to
the main shaft of the hour, minute and second hands. There is a compound gear with
10 teeth that turns two gears: a 32 tooth gear and a 108 tooth gear. The 32 tooth
gear contains a compound gear with 8 teeth that turns another 32 tooth gear connected
to the main shaft (hour, minute and second hands). The 108 tooth gear contains a
compund of 18 teeth that turns another 108 tooth gear. The latter 108 tooth gear
is also connected to the main hour, minute and second hand shaft.
Steve kept all gear centers along a vertical plane. This makes for a convenient
means to stand the mechanism. Additionally, the gear centers have an adjustable
groove on the frame so that the gears can be adjusted for best gear meshing.
To
drive the pendulum, Steve is using an ATMega controller acting as an Arduino
(contains a bootloader that allows for the ease of using Sketches and simple code
transfer). The controller receives a signal from the pendulum when it is at vertical
at which point, a voltage is applied to a coil, pushing the pendulum. The creative
aspect to this is Steve determine that this pulse is not required at every pendulum
swing.
Check out Steve's blog for detailed
information.