D.I.Y. QUIET Lifting Platform-Plan

A simplified, low cost platform that adequately dampens noise and
vibration can be built with minimal effort and expense. Two platform
lengths are suggested: 6’ and 8’. The 8’x 8’ platform requires less cutting
of material than the 6’x 8’.

A. Cushions: The drop cushion is a composite of old carpeting and carpet
foam padding sandwiched in layers and built up to about 8” thick, topped
with a ¾” horse mat to distribute the weight across the cushion. The
cushions fit into the cushion wells. The 5” thick cushion didn’t work too
well, but 8” seemed to dampen the vibration and noise to a whisper (we
test-dropped 150k from full height.) Place one layer of carpet on the
bottom of the well, add the carpet pad pieces, and then place a carpet
layer on top. You can add more carpet layers in between the pad pieces if
you have them. Try to keep the majority of the cushion comprised of
padding since it does most of the cushioning. The carpet adds strength
and keeps the pads from disintegrating by direct contact with the horse
mats or bumper plates. Additional cushion thickness might be needed for
big weights. It is a simple matter to build more cushions and adjust the
center section height by adding more sheets of plywood/horse mats.
After assembling the platform and cushion well, cut the padding and
carpeting into 2’x 8’ pieces and stack enough of them together inside the
wells until the height (including the top horse mat layer) is level with the
center section. Test with a barbell loaded and pressing down on the mat/
cushion. Since horse mats are usually 4’x 6’, cut one in half to get (2)-2’x
6’ pieces.

B. Platform Frame and Cushion Wells: The base of the platform is made
from (4) - ¾”x 4’x 8’ sheets of plywood, with 2 sheets rotated 90 degrees
to the other sheets, and fastened together with 1 ¼” drywall screws. The
center section is built up from either (11) - ¾”x 4’x 8’ sheets of plywood
with a ¾” horse mat placed on the top of the plywood or (12) sheets
without the horse mat. Alternatively, the center section can be a floor
joist frame structure to replace the multiple plywood layers. The floor
joist structure would use 2x6 joists spaced no less than 12” apart, to
support the lifter adequately, with (3) ¾” thick pieces of plywood and a
horse mat on top of that or (4) sheets without the horse mat top layer.
Use 1 ¼” drywall screws to assemble to layers of plywood together and to
fasten the first layer to the plywood base. Use 2 ¼” or longer drywall
screws to fasten the 2x6 frame members together. Use 2 ¼” drywall
screws to attach the 2x2 cleats to the plywood base.

C. List of Materials for 8’x 8’ Platform

(2)-8’ 2x2’s
(2)-8’ 2x6’s
(2)-8’3” 2x6’s
(7-8 with or without horse mat top layer)- ¾” x 4’x 8’ plywood (For the
Center Joist Floor design) or
(15-16 with or without horse mat top layer)- ¾”x 4’x 8’ plywood (For the
Solid Center Design)
(3)- ¾” x 4’x 6’ rubber horse mats (For Top Layer of Center Section and
Top of Cushions) or
(1)- ¾” x 4’x 6’ rubber horse mats (For Top of Cushions with ¾ “ plywood
for Top of Center Section)
(40)- 2’x 8’ pieces of foam carpet pad (get used pad free from carpet
stores)
(4+)- 2’x 8’ pieces of carpet (get used carpet free from carpet stores)
(1 #) – 1 ¼” drywall screws
(24) – 2 ¼” drywall screws

D. Key Dimensions:
                                    
Outside dimensions: 8’3”x 8’3” or 6’3”x 8’3”
Center (lifting) section: 4’x 8’ or 4’x 6’
Outer cushion (weight drop) section 2’x 8’ or 2’x 6’,
Minimum cushion thickness: 8”