I got my idea for the Grinning Reaper design, based on the short-lived Resin Reaper that briefly appeared in the market place, and Roger, a retired nuclear welder and skunk pharmer, whomped up the test sled, which turned out slick!
A relatively simple device, that is smaller than the Resin Reaper, but which produces about ~10% primo quality kief by weight from frozen bud in 3 to 5 minutes, while being less messy than the Resin Reaper.
We place frozen material on the screen and set the vibratratory nylon plate on top, where it just floats and shakes. The vibration is from a broken palm sander, that had a broken sandpaper clamping system, which we discarded.
Because the vibration is on the horizontal plane, it produces far more shear energy than a tumbler, while producing less fine plant material.
We built the Grinning Reaper entirely from scrap, aside from the 130 micron stainless screen that I purchased for $6.50 for the one sq/ft used from Howard Wire and the foot pads purchased locally from Ace Hardware.
The frame was constructed from 304SS 1 1/2 X 1 1/2″ square tubing, and the legs from 1 1/4" 304SS angle iron.
Roger added the skirts to prevent the material from bouncing up through he cracks between the vibrating plate and the screen, and contaminating the harvest tray underneath, which was a problem with the Resin Reaper.
Here are some different shots to better illustrate the Grinning Reapers design and construction:
Grinning Reaper base
Above is the base, and below is the bottom side of the base. Note the mesh tensioning screws on the right side.
Inverted Grinning Reaper base showing screen tensioning
Top of floating pad with hand sander
Bottom of floating pad
Above two of the top plate with the palm sander attached. Note the door weather stripping on the perimeter to minimize material jumping out of the sieve during operation.
Yield after 3 minutes
A three minute yield. We found that at 30 hertz, three minutes produced about 50% yield and beyond was where green color began to creep in.
Grinning reaper with ultrasonic transducer
Of course we had to try a few more things. Here is a 60W ultrasonic transducer attached to the top plate, but alas it proved to be grossly under powered.
Hee, hee, hee, as we still covet sieving to music, I looked for a used acoustical seat shaker and fortuitously fortune smiled upon me, by placing a 50W acoustical seat shaker in my hands for under $50!
Stay tuned as this project unfolds………………………………..