By David N. Goodchild

Here's another way to get more use out of the Radial Arm Saw (see Cutting Heavy Metal for another). On the opposite side of the motor shaft from the saw blade is usually another arbor. This is often used for line boring if you have the chuck and some other accessories. I use it for a disc sander however.

My radial is a 10" Craftsman, about 25 years old. Yours may be different but a change in relative sizes will probably allow you to undertake the following modification with little difficulty.

First, you will need to cut a plywood disk of the size you wish to use for the disk sander; I made mine 12". (You can make them a little larger than the capacity of your saw since there is no interference from the rear arbor and you can always raise the saw head to accommodate a larger disk) Don't make them too much larger however as this stresses the motor a little too much I think.

Measure the size of the threaded arbor, then go out and buy a floor flange that will fit. Mine was 1/2". Now, before anybody rears up on their hind legs, I know that a floor flange is a tapered plumbing thread and that the arbor is a machine thread, BUT, at least on my Craftsman, this works.

Place the floor flange over the center of the plywood disk and screw it down.

A hint here. If you cut out the disk on your bandsaw or bench saw or with your router, you will have a center point identified. Get a drill bit that will just fit through the threaded center of the floor flange. Insert it through the floor flange and position the point of the drill bit in the center point on the disk. Make sure the drill bit is straight and plumb and screw down the floor flange; it will be in the center of the disk. This is important to minimize vibration.

You might need to buy a larger floor flange than you need and use an adapter to size it down to fit your arbor; that's ok, the larger flange is fine.

Disks come with adhesive backing and without. I buy plain-backed disks and just use a little rubber cement to adhere to the plywood. (I coated the ply disk with epoxy to make a good, non-absorbent surface). This way I can remove the disk when it gets pitched up and worn, with a little rubber cement thinner.

Screw the assembly onto the radial arm saw. You can clamp a block of wood onto the table for use as a work rest. One item of caution here. ALWAYS BE SURE TO SAND IN SUCH A WAY THAT THE DISK TENDS TO TIGHTEN ONTO THE ARBOR RATHER THAN LOOSEN. That way it won't spin off in your face. Also remember, that this direction will change depending on to which side of the table you swing the head. If the disk is facing to the left, the rotation of the disk of my Craftsman is clockwise as I face it. If the disk is on the right of the table, the rotation is counter-clockwise as I face it, the same as the blade.