Companion video can be seen here: http://www.youtube.com/watch?v=jUKrmTN7S24
We recently replaced 2 of our platforms with heavier duty versions. Here is how we constructed them. Our design follows the most popular theme out there, but we made 2 main adjustments. We cut handholds into the base to allow a degree of movability, and we only had access to rubber sections that were six feet long. Total cost for materials is about $200.
Materials List:
(1) 4x6ft rubber sheet, ¾ in thick
(4) 4×8 sections of plywood sheathing, ¾ in thick
(1) sheet of 4x8ft MDF, ¾ in thick
2x4ft section of scrap MDF (if you are making multiple platforms, just buy an extra sheet)
3 cans of liquid nails (plus application gun)
2lbs each of 2in and 1.25in coarse thread drywall screws
Tools: Drill and drill bit, Screwdriver, jigsaw, skillsaw, chalk line, measuring tape
Directions:
Take 2 of the plywood sections and cut handholds in them. You will be making 4 sets of handholds on the finished platform. On the 4ft end, measure about 12in from the edge and draw out rectangular handholds about 4in wide. Use a drill bit to put starter holes in the corners of the handholds. Use the jigsaw to cut out the handhold.
Cut down the MDF to size. The MDF is slightly longer than the plywood. Lay a sheet of plywood on top of the MDF and square them up. There will be a slight overhang on the long and the short side. Mark and cut off the overhang on the SHORT END ONLY (the 4ft end).
Make 2×2 sections of MDF. Use the scrap MDF you have to make (2) 2x2ft sections.
Lay the first layer. Lay down the plywood with the handholds cut into it and square it up. Apply the liquid nails with a ¼ in bead in an S-shaped pattern, paying special attention to the edges and around the handles.
Lay the second layer. Lay down the second layer of plywood perpendicular to the first (rotate it 90 degrees). As you lay each section down, square it up and put 1.25in screws in each corner to hold them in place.
Secure the second layer to the first. Drop chalk lines along each edge and perpendicular to the long end of the second layer. Drive in screws approximately 8 inches apart. The center chalk line will correspond to the seam between to two sheets in the first layer. Instead of dropping screws directly into this chalk line, place a row about 1in to either side to create a double seam. Drop 5 or 6 screws around the handholds in a horseshoe pattern to help reinforce those also.
Cut the rubber. Measure the midpoint of the 4ft end of the rubber sheet and drop a chalk line. Wedge a 2×4 underneath the mat. Use a box cutter to lightly score the chalk line. Keep working to deepen the cuts; the initial score mark should act as a guide. When done you will have (2) 2×6 sections of rubber.
Lay the top layer perpendicular to the second layer. Lay the 4×8 MDF sheet in the middle and the two rubber sheets on the side. There will be 2×2 gaps at the top of the rubber. Lay the 2×2 sections of MDF in these gaps. Square everything up and drop 2in screws in the edges of the MDF and the rubber. Be sure to make the screws flush to avoid snags.
Ready to lift!
June 6th, 2011 → 2:19 pm
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