Introduction: Simple Wood Sit-Up Bench
This tutorial will show you how to make a simple but sturdy sit-up bench that you can make in just one afternoon. I normally focus primarily on running for keeping in shape, however, I recently injured my knee and I am still recovering. In the meantime, I wanted to find other ways to stay fit. Since gyms in my area are closed and gym equipment is very expensive, I decided I would DIY it.
- 3/4" plywood
- Wood Screws, 3" and 1.5"
- Paint (optional or you can use wood stain)
- Thin Plastic Tarp, Plastic Sheeting or Water Proof Fabric
- Flat Packaging Material
- Electrical Tape
- Tyvek or Packaging Tape
- Miter Saw
- Circular or Table Saw
- Cordless Drill
- Paint Brush
- Staple Gun
- Tape Measure
Step 1: Cut the Boards
First you will need to cut the 2"x4"s to the following sizes:
A - 2x 14"
B - 2x 20" with a 20° angle cut through the long side of the board
C - 1x 52" with a 20° angle cut through the short side of the board
Now cut the 3/4" plywood so that it is 52"x12"
Step 2: Build the Frame
To build the frame, first, you must attach the longest board to the two 20-inch angled boards. Set the longest board so that it is resting on its narrow side. Place one of the 20-inch angled boards so it's non angled corner lines up with the non angled corner of the longest board. The shorter board should be lying on its wider side, you should use another 2x4 to elevate the other end. Install two 3" screws through the shorter board into the longer one, making sure that the corner stays aligned. Now flip over the two boards, and set up the other 20-inch board so that it mirrors the other one. Screw in the second board just like the first use.
Step 3: Add Feet
Next, you need to add feet to keep the frame from tipping over. Use a tape measure to mark 3.75" from both ends of one of the 14-inch boards. Now on the tall side of the frame, place the 14-inch board under the two angled boards using the marks as guidelines to make the board centered. Drill screws through the vertical boards at an angle into the footboard. On the other 14-inch board, measure about 5.25" from either end. Flip the frame upside-down and predrill two screws partly into the end of the longboard. Tilt the frame so the long part is sticking straight up, now place the remaining 14-inch board that you just marked on the top, it may want to fall off, just hold it in place. Line up the marks with the board and drill in the two screws, keep firm pressure so the board doesn't move while you do this.
Step 4: Cut Foot Hold Boards
Next, we need to make the place for feet to hold onto. To do this first cut a 2"x4" to 18 inches, then create a 50° angle through the narrow side of the board. You will also need to cut a large dowel to 14 inches. The last thing you need to do prior to assembling the foothold is to file a notch in the non angled end of the 2"x4". Use a file to create a shallow round at the end of the 2"x4" so that the dowel has somewhere to go.
Step 5: Assemble the Foot Hold
In a vice, clamp the dowel so you can drill into it without it moving. Here I recommend drilling pilot holes and then predrilling the 3-inch screws slightly into the dowel. Now clamp the 2"x4" board in the clamp with the filed side facing up. Place the dowel on top so it is centered, then hold it in place and drill the screws all the way in. You should now have a T.
Step 6: Install the Foot Hold
Now you will install the foothold. Start by measuring from the top of the frame alongside the longboard, make a mark at 6 inches, make sure the mark goes all the way down the narrow side of the board. Insert the foothold between the two flanged frame boards, you may need to loosen some of the top screws to do this. Line up the inner end of the board with the 6-inch mark. Once it is flush, you can add a 3" screw through the boards on either side and two 3" screws in through the top. If you loosened any screws, make sure to tighten them now.
Step 7: Add the Bench Board
Now you will add the main bench board. Place the piece of plywood on the frame so that the end is flush with the corner. Use a tape measure to center the board on the 2"x4" under it. Once it is centered, add 1.5" screws along the center from the top to the bottom. At the top of the board, add two 3" screws into the two 20-inch angled frame boards.
Step 8: Sand & Paint
Next, use sandpaper to soften the boards. The most important spot to sand is the top corner, I sanded this until it was round. If you would like to paint your bench, you can do so now. I am going to add a cushion to mine so I only painted the bottom and sides.
Step 9: Add Foot Padding
Next, you will add cushions to protect your feet. Cut sections of recycled packaging material to rectangles of about 5"x6.5". Wrap the rectangles around the two round footholds, use Tyvek or packaging tape to keep the cushion material in place. Next, wrap the footholds in electrical tape, this will make them more durable and keep the black color scheme.
Step 10: Add Main Cushion
Next, you will add a cushion to the main bench board. First cut a piece of flat foam/packaging material to 52"x12", if you need to, but multiple pieces and adhere them together with Tyvek tape. You will also want to cut a piece of thin tarp or fabric to 54"x18". Place the piece of cushion on the bench, rather than lining it up, you want the top end to overhang by 2 inches. Use a staple gun to staple the top end over the corner. Add staples to the bottom as well, through the cushion into the plywood. Finally, add two or three strips of Tyvek tape around the cushion to keep it from sliding around.
Step 11: Adding the Cushion Cover
Now that the cushion is in place, you must add a cover over it. Place the tarp or fabric over the bench. It should overhand a few inches on every side except the bottom, which should end with the cushion. Use a staple gun to add at least 3 stables to the top corner. Next, stretch the material as much as you safely can and add a few stables to the bottom into the plywood. Finally, flip over the bench and add staples to the loose sides of the tarp, stretching it as you go to make the surface taut. Once you have finished stapling, run your hand along the edges to check for any loose areas, if there are any, add more staples. You can also use a hammer to set the staples deeper into the wood.
Step 12: Finishing Touches
To make the bench a little more polished, you should add electrical tape or gaffer tape to cover up some of the staples. Add a few strips of tape to the top corner to cover the row of stables. Add a few strips of tape to the bottom as well to cover up the staples there.
Step 13: Get Fit!
That's it! Your sit-up bench is done, now all you have to do is use it. I hope you enjoyed this quick and simple sit-up bench tutorial.
Second Prize in the
Exercise Speed Challenge