Posted by John Griessen on May 14, 1999 at 18:02:10:
In Reply to: vibrating table posted by M. Markham on May 08, 1999 at 11:40:32:
Thinking laterally, vibrating is essential, the table is not....
So, consider using a method borrowed from concrete
poured foundations for buildings. They use a
vibrating eccentric weight to send shock waves into
the liquid slurry to make it more liquid, and dislodge
bubbles by cavitation or at least compressing/expanding
them some. If their scale is right for you, just buy one.
I made one the right scale for investment casting debubbling
from a Weedeater crossed with a Waring Blendor, (of course,
this has absolutely nothing to do with my style of art).
The end of the flex
shaft of the weedeater had a hole in it that I tapped to
receive the threaded end of the Waring motor shaft. The
weedeater business end I modified with a welded on
eccentric weight small enough
to stay within the aluminum bearing housing, then covered
all with a PVC hose and copper end cap with inner tube
and band clamp for good measure.
I drive this motor vibrator combo with about 50 Volts
DC for the right speed to shake bubbles while working
it down between burnoutables and mold
cannister. The fluidizing effect of the vibration allows
much easier motion than without, so my burnoutables
float out of the investment--you need your
other hand free to guide them as you guide the
vibratool. That means a foot switch. So far, I have
found the constant 50 Volt speed seems enough--I use an
on/off foot switch. A variable speed might have value.
I use a Molex connector and a special cable I made to
plug into my 50 Volt DC kiln area power(I use that
voltage for safety reasons to drive all motors in
the area of the kiln, furnace, and crucible tongs).