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Old 09-05-2006, 03:45 PM   #1
Allan Luomala
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Join Date: Sep 2006
Location: Angus/Borden  ON
Posts: 173
Hey all.

After covetting Lincoln's classic plyo box, I decided I had to undertake the challenge. I have found myself using pretty dodgy platforms (at the base gym, and at home) to do my box jumps, so I decided to make my own plyo boxes. I used Lincoln's basic concept (link: http://www.crossfit.com/discus/messages/26/14917.html), and then decided to "trick it out" a little, as I wanted to practice my woodworking skills, and justify the expenditure of all the money on the power tools that I conned my wife into believing that I would really, really need ;}

I decided that I would make a "modular" plyo box, that has a 24" main body, and a 6 inch additional base that can be attached/detached to make it 30"/24" as required. I figured I didn't want to make a 24" AND a 30" box just for myself (I am cheap and lazy).

Because I have a variety of power tools (table saw, mitre saw, router, jigsaw, electric planer, orbital sanders, drill press) but not a dedicated shop, I was reliant on good weather and had to work outside. I sketched out my idea, and then used SketchUp (free, and VERY handy to build things like this. Link: http://www.sketchup.com/) to create my plyo boxes. I then "exploded" the parts onto a virtual 48" X 96" (4ft by 8 ft) sheet of plywood to a) see if it would fit onto one sheet of plywood (it does, but more about that later), and b) give me a "blueprint" to draw out my plans.

http://www.crossfit.com/discus/messages/26/29726.jpg

http://www.crossfit.com/discus/messages/26/29727.jpg


I made a smaller scale size model first off with a scrap piece of plywood to see if my ideas would work, the angle I would need to use to make the box sit flat, in particular. As per Lincoln's box, I decided to make it angled (smaller top than bottom) for two reasons: 1) make it stackable and 2) eliminate the potential for ripping all the skin off my shins with a 90 degree angle on the top surface. Hindsight being 20/20, I should have gone with a simple 90 degree 24" high cube, and then made a 6" add-on to make it into a 30" box. Why???? It was a lot of freakin' work to get all the angles squared away (no pun intended), and I could have just used a 45 degree bevel router bit to remove the sharp corners (or a rounded bit). I digress.......

http://www.crossfit.com/discus/messages/26/29728.jpg

I had allowed myself about 5-6 hours for this project. Yeah, whatever...... Pretty much anything that could go wrong, did. 1) Not securing table saw extension. Result: not so square initial cut. 2) Not being able to read my own pencil marks. Result: countersunk screwholes in wrong place. 3) Not taking into account SketchUp blueprint not being 100% accurate. Result: landing platform too small, resulting in some fast thinking, so as to not have to drive 1.5 hrs (round trip) to buy another sheet (or partial sheet) of plywood. If you plan on using my drawings, DON'T!!!. I have to modify them to allow enough space for a larger top square (landing platform). You can modify the upper (smaller) part to be smaller, as you can't just make it shorter (platform would still be too small). I solved this particular problem by cutting some 2X2's with a 8 degree cut to one side, and then screwed them to the inside at the top, and then screwed from underneath into the landing platform. I cut the platform to a 45 degree angle, and used a 45 degree router bit on the top of the sides of the box to make it match (more or less). I think it actually worked out better (for my shins sake, anyway) than the originally planned 8 degree cut I was going to do to the sides of the platform.

http://www.crossfit.com/discus/messages/26/29729.jpg

http://www.crossfit.com/discus/messages/26/29730.jpg

The tools I had definitely helped me out, as did the conviction to try to make it "right" rather than doing it half-assed (as I started to feel the urge to do after things started to come apart). The biggest motivator was the fact that I dropped $45 on the plywood (3/4" maple veneer), as I wanted something with a tougher exterior than the pine junkie plywood you can get for cheaper.

I used 2.5 inch screws, spaced about 4 inches apart, which was likely overkill, but I don't think that bad boy will fall apart any time soon. I used some leftover stain and lacquer from a refinished project to finish it (rather than paint over the beautiful maple veneer), and then put a final 2 coats of anti-skid compound (from Home Depot) into the laquer and spread that on top. I was going to go with the strips of no-skid tape, but I figured I would try out that stuff. I added some latches and corner pieces to keep the top secured to the bottom when it is in 30" mode, and I put pads on the bottom of the 24" and 6" section so it wouldn't slide around like to one box I used before did. Getting the 24" section and 6" section together with the pads on involved a bit of head-scratching, and a Forstner drill bit, but worked out better than I expected (and keeps it together better, I suspect).

http://www.crossfit.com/discus/messages/26/29731.jpg

http://www.crossfit.com/discus/messages/26/29732.jpg

http://www.crossfit.com/discus/messages/26/29733.jpg

Anyway, that's my story of "How I Pimped my PlyoBox". I must thank Lincoln for his inspiration, and to all the other people who have shown that, with a little imagination and the right tools, who needs $5000 pieces of equipment to get fit??!?!!

Next project to post: my outdoor workout area (done at same time as plyobox and building a retaining wall for ditch, as well as finishing off my deck.... all the spare wood from the various projects came in handy for my workout area).

Al
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