Intro: Air Hockey Table
This homemade wooden air hockey table was made out of a piece of MDF, orientated chip-board, and several pieces of lumber.
Step 1: Step 1: Prototyping, Design and Calculations
Prototyping and Design:
Before I began constructing my air hockey table, I first drafted up a CAD model in solid works to give me a better idea of how I would construct each component and how they would all fit together. I also considered the order of operations in which each component should be assembled. Then, I created a miniature air hockey table to act as a proof of concept.
Depicted above are my calculations for the volumetric flow required to achieve a jet flow of 50ft/s in each flow (Q= volumetric flow, V = flow rate/jet flow, A = cross sectional area of each hole). To calculate the total volumetric flow rate, I multiplied Qn by the number of holes n.
Step 2: Step 2: Constructing the Frame
- Table Saw
- Miter Saw
- Power Sander
- Tape Measure
- 3 pieces of lumber (2in x 6in x 96in)
Instructions: Begin with a 2in x 6in x 96in piece of lumber.
- Use a tape measure to mark out 64 inches a piece of lumber's long axis. This will be the side rails of the air hockey table (You may choose an appropriate length depending on the dimensions you have chosen).
- Cut the lumber at the marked point, and repeat the process for a second piece of lumber.
- Using a tape measure again, mark off the midpoint of the third piece of lumber at approximately 48 inches. This will be the end rail of the table.
- Use the miter saw to saw the lumber in half.
- Next, use a table saw to cut slots in each piece of lumber. The slots should measure 0.5 inches (+0.05 to 0.1)in width and its left edge should be 1 inch (top slot) and 3 inches (bottom slot) from the side of the lumber respectively. View the schematic attached for details (note that depending on the size of your table saw blade, you may have to take several cuts before the slot spans half an inch in length). Do this for all pieces of your lumber (two long pieces and two short pieces).
- Next, mark out the mid point of the shorter pieces of lumber. Then, draw a 8 inch x 1/4 inch rectangle centered at the mid point and with its center 1/8 inch offset from the top edge of the top slot. These will be the goals. View the schematic and images for clarification.
- I used a chisel to approximately cut out the shape of the rectangle, then used a router with a 1/4 inch bit to smoothen out the cut.
- Use sandpaper or a power sander to smoothen out any rough edges.
Step 3: Step 3: Constructing the Playing Surface and Bottom Surface
- MDF sheet (1/2 in. x 4 ft. x 8 ft)
- Chipboard (1/2 in. x 4 ft. x 8 ft)
- Drill/1/32 or 1/16 drill bit
- Track Saw
Instructions: Begin with a piece of MDF (1/2 in. x 4 ft. x 8 ft)
- Using a track saw, cut the MDF and chip boards to length (63in x 47in).
- Lay the MDF sheet on a table, and use a ruler to draw lines 1 inch apart across and along the entire board to form a grid (I decided to use MDF because the material is easy to drill through).
- Then, for every other intersection on the gird, use a power drill with a 1/32 drill bit (or 1/16 depending on your decision choices. Note that the calculations were done for 1/32 sized holes) to drill through the MDF board. Don't use too much force or else the drill bit will break!
- Then, flip the MDF board over, and use a power sander to deburr the holes and to smoothen the playing surface.
- Use a 2 inch hole saw to cut a hole approximately at the center of the chipboard. Since I did not have access to a hole saw, I ended up using a power drill with the largest drill bit I could find. This is not recommended! This hole will be where the PVC pipe will be attached.
Step 4: Step 4: Assembly
- Power Drill
- Impact Driver
- Hot Glue Gun
- 2in PVC pipe
- On each of the side rails and end rails, use a power drill to create pilot holes (1/8 inch) along both the top and bottom slots.
- Layout all the side rails and the chip board flat on the ground or on a table.
- Slide the side rails and one end rail along the bottom slot. You may have to use a mallet to aid this process. When constructing my table, the pieces of lumber had become warped so I had to cut the slots ~0.1in thicker to give some leeway.
- Using the impact driver, drive screws through all the appropriate pilot holes to secure the chipboard to the frame.
- Use a hot glue gun to seal the intersection of the rails and the chipboard. We want an air tight plenum!
- Slide the MDF board along the top slot. Once again, a mallet maybe required to properly fit the boards on.
- I found laying the entire frame on its side and utilizing gravity to pull the boards down was helpful. I then used a mallet to gently tap the boards to fit them in place.
- Finally, attach the second end rail on the other side.
- Use the impact driver to drive screws in all the pilot holes to secure both boards.
Step 5: Step 5: Hockey Pucks, Pusher, Touching Up
- 3D printer
- Hot glue gun
- Mineral oil
- To create the hockey puck and pushers, I used fusion 360 to create stl files then used a makerbot 3D printer to print the designs. I experimented with different infills to see what density was optimal for the hockey puck given the amount of air flow from the table.
- After the frame was attached, I used hot glue to line the edges of the table to prevent air loss.
- I then used mineral oil to apply a finish on the lumber.
Step 6: Tips:
- As depicted above, initially my plan was to cut ridges in each end rail so that the end rail it self could be slotted into the side rail to create a tighter fit. However, the entire process that started from chiseling to sanding was too time consuming and thus I abandoned the idea.
- If you find your surface board bowing down towards the center, consider adding tiny wooden block pieces in the plenum to provide support. I decided against doing this since I was unsure about the effects this would have on air flow.
- If you have access to a large enough shopbot, consider using it to drill the holes on the playing surface to save time!