Transcription
Got a small home climbing gym, and in between climbing sessions, we try to find something to do while our arms are recovering. So, I'm going to try to make a plyometric, CrossFit-style jump box to do box jumps on.
This particular plan I found online, what intrigued me about it is you only need one sheet of plywood, 4x8, a bunch of screws, and that's it. No other bracing lumber, no complicated cuts. It's pretty bare bones and basic, but simple, and I want one. So, I'm going to build this, make a video, hopefully helps somebody else out that wants to make one.
You end up with three different jump heights with the same box, just by rotating it on the ground: 20 inches, 24 inches, and 30 inches. So, not super tall, but some variety anyway. And I'm going to show you where the cuts go, and then I'll get cutting.
Okay, now I'll show you where to draw the lines to make all of your cuts. I did lie, I think there is a little bit of scrap you'll end up with when you're finished. Your first cut, assuming you put your board like I have, landscape format, so 4 feet by 8 feet. This first cut is going to be 20 inches in from the edge, draw a line straight down. Then go another 19 inches, draw a line straight down. Then go 28 inches, draw a line straight down. So, that is going to give you four different sections: a 20-inch, a 19-inch, a 28 and a half inch, and a 28 and a half inch.
Now, there's just a few horizontal lines you need to draw. Come back to this first section, which is 20 inches wide. Come down halfway, which is 24 inches, and draw a line. The next section, number two, no horizontal lines. I believe this becomes your scrap. Come to the first 28 and a half inch section, which is your third section in from the left. Come down 18 and a half inches, draw a horizontal line. Come down another 11 inches, draw a horizontal line, and then you will end up with another 18 and a half inch depth here. Your last section, section number four, come down 24 inches, which is halfway, draw a horizontal line, and you got it.
So, I'm going to cut all those out, and then I'll start assembling. Not going to film the cutting. I'm just going to be using a hand skill saw. I don't have a table saw, so just it'll take me a long time to make the line super straight, so that'd be pretty boring. But when I resume, this will all be cut out. Tada!
All right, I've now made all my cuts. And again, here is that first section. Those two pieces are 24x20. Those are going to become the end caps of the box. Over here, the main box, the side walls will be comprised of this board, this board, this board, and this board, and the 11-incher that's in the middle there. That'll become a cross brace, kind of like a beam that will go inside the box. Show you that in a minute.
But right now, using these four boards, I'm going to build the outer wall structure of the box. And I've now screwed the four sides together. I just butted everything up and then I put screws along the edge. What you'll want to do first is take one of your end caps, lay it down on the ground, and then build your walls around that, and just make sure you're doing it right so that they fit. If you've got the walls assembled perfectly, these end caps will be pretty flush with all of your walls. So that's about what that's going to look like.
So, before I screw that on, I'm going to take a 2x6 and I just want to put a handle in the finished product so that you can lug it around. So I'm going to put a 2x6 right there near the corner on the end cap piece. I'm going to trace around on that. Looks pretty good. Easy to carry. Then I'm going to take a drill. I'm putting a 5/8 bit in there. Could be half inch or whatever you want, but I'm going to put that as close to the corner of each of the corners of the rectangle that I just drew with the 2x6. Always wear goggles.
Okay, so I've put holes in the corners of the handle. Then I'm going to take a jigsaw. I'll take a jigsaw and I'll just saw along the lines that I drew, and then I'll end up with nice rounded corners. Gives you good. Those holes make a nice place to start with the jigsaw in the wood. Okay, I got the jigsaw, got my goggles on, and I'm going to saw these lines to make the handle.
Okay, got a nice handle. Saw that up later. So now you're going to want to repeat that on the other end cap and screw those end caps on. On the other one, make sure it's just exact opposite side so you can pick this up. It's going to be pretty heavy when it's done. I got one handle on an end cap. It's on the bottom. That piece is already screwed on the four walls. Now I'm going to take this 11-inch brace and I'm going to put it right in the middle. Handle down there. This is in the middle, and I'm going to screw that in. Then I'm going to put the other end cap on.
I now have the cross brace in. These four screws are going into the 11-inch side of the cross brace. That helps transfer the load when you're jumping on the top into the sidewall. Screws along the top going into the top spine of the cross brace. Then I'll put the final end cap on this side and also screw four screws into the 11-inch end of that cross bit brace. And that'll have another handle that will be on this side, but exact opposite of the existing handle that I've put in there. And then it's just a bunch of sanding, and you're pretty much done.
This will be the top, and you'll want to mark that because you'll want to jump on this side and not this side because you have your cross brace here, which transfers the load of you jumping on this side. Which is not this top board isn't on top of these end pieces. That's the purpose of this cross brace is to transfer that load into the end cap when you have turned it to jump on the tall end, or turned it this way to jump jump on the shortest height. It doesn't matter because the top board you're jumping on, the load gets transferred into these sides. So you just want to be sure and mark the top so you know where the cross brace is when you're jumping on the medium height, which is 24 inches, I believe. And I'm going to do some sanding, do some marking of where that is, and then it's done. I'll take a picture to show you.
Okay, the box is pretty much done. The structure is complete. I just have some finished work to do on it. Got the nice handles. Those are pretty much necessary. It's heavier than it looks. They're on opposite sides so you can just pick it up. I've also got the cross brace across this top side on the inside. You can see the screws there, and gives you a combination of three jumping options: 20 inch, 24 inch, and 30. I underestimated how hard the 30 would be to do very many of those in a row. It's pretty good challenge. So, yeah, pretty much done.
I'm going to do some sanding. Going to sand all of the corners really heavily, make them nice and round. These are known to be shin busters, so something you want to do. Also, finish all the flat surfaces too, just to make them smoother and make this thing look a little bit nicer. And throw the photo at the end of this and enjoy. Good luck.