This saber saw can be used normally, or mounted upside-down and used as a scroll saw. Two tools in one! Note the different PVC "foot" designs that hold down the work. The first photo shows the improved blade safety shield, which is the one you should follow.
The old foot design is OK if one is careful not to touch the blade with a finger, but the safest design is the new one.
Step 1: Details of the Design
The foot that holds down one's work, and other parts are made out of PVC plastic. PVC can be heated to form it. Be careful not to burn it, to avoid toxic fumes. I use either a gas stove or a propane torch for heating.
The saw slides forward for removal from the wooden frame. The frame has two pieces of 2X4 screwed to it that bracket two sides of the work table. The clearance is tight and all it takes is a small PVC wedge in the crack to lock the frame firmly to the table.
On the bottom side of the frame is a PVC piece screwed to the wood that applies pressure to the saw housing. That holds the metal base plate of the saw firmly against the wood on the other side and keeps the saw from vibrating up and down. The foot that holds the work down keeps the work from vibrating up and down.
Step 2: Wire Adapter for Cutting Circles
A recent project involved cutting circles out of rubber floor mat material. I needed a center point pin at an adjustable distance from the saw blade to rotate the foam around.
To cut the material, I first punch a hole at the center point with an ice pick. Then, the bent down tip of the wire tool is poked through the hole. I trim the foam in with scissors at one point to bring the saw blade in to the radius distance. Clamp down the wire to the base, turn on the machine, and rotate the foam to cut the circle.
Step 3: Improved Blade Safety Guard
Since publishing this instructable, I have modified the holding "foot" to also be a blade guard.
The guard is made out of heat formed PVC plastic, using a gas stove to flatten the pipe and a propane torch to bend the section that covers the blade. I used some 1/2" plywood while folding the PVC in order to keep the gap space uniform.
I had to saw a slit in the front of the guard in order to see the blade as it cuts, for precision cutting. Two sheet metal screws in elongated holes adjust the height of the foot.
When I was a kid, our scroll saw (what we mistakenly called a jigsaw at the time) had no guard above the foot, so we were just careful not to get cut. I was told at the time that continuous direction blades, like band saws and table saws were much more dangerous than the up and down scroll saw blade. More or less dangerous is still dangerous, though, so I suggest you use this blade covering design.