Step 1: Find the Matching Diameter in PVC
I had a bunch of PVC laying around in different diameters so I found the one that matched the table leg. It was only 3-4mm larger which would be solved with a little wedge. I wanted to raise the tables by 18cm, so I cut the PVC sleeves double that.
Step 2: Cut Wooden Blocks
I had a piece of 2x10 from a shipping skid that was a decent fit. I wanted something a bit too large so that I could get a nice, tight friction fit. I cut it into a block, then used the mitre saw to cut the 18cm lengths to fit inside.
Step 3: Smooth the Edges
I used the router to round the edges of the blocks then put them on the belt sander to bring them down just a tiny bit more for a nice snug fit.
Step 4: Insert the Blocks
The final step was to push the blocks into the sleeves and knock them in. Once they slid over the table legs, a chopstick made the perfect wedge and the table was solid.
Step 5: Engaging Teachers
Some teachers had been using the sorts of risers you see in the picture. Not only are they less stable, but they cost $25 a set. But the best part of this project was that I managed to get people in the room and engage them in the process. My thinking is that the more comfortable they are in here, the more comfortable they will be bringing their students in to make stuff!