Disk Sander

Build this disk sander with parts that are probably sitting around your shop gathering dust. All you need is a 1/4 hp or larger 1750 RPM electric motor, a v-pulley, switch, electrical cord and scraps of wood.

Assembly

Step 1

Measure and make a note of the height of the center of the motor shaft.

Step 2

Mount the motor on a base of 3/4" thick plywood that is at least 14" wide and 10" deep. The shaft must protrude over the front edge as shown.

Step 3

Cut two blocks to mount table, distance "X" is the height of the motorshaft center minus thickness of table material.

Trim two of the corners out as shown.

Step 4

Cut a 9 1/8" dia. circle from 3/4" plywood. Drill three holes 1/4" in diameter in a V-pulley, center pulley on the face of the disk and mark position of holes. With a 5/8" spade or forstner bit drill 1/8" deep inserts for carriage bolt heads. Drill 1/4" holes through disk and fasten pulley to it with carriage bolts. Install disk and pulley assembly on to motor shaft.

Step 5

Fasten the two table brackets to the base, with two screws in each, allowing a minimum of 1/4" clearance for sanding disk.

Step 6

Fasten two strips beneath base to allow clearance for disk.

Fasten 3/4" thick 6" X 14" table to brackets with 1/4" carrage bolts, sink the heads using a 5/8" spade or forstner bit.

Step 7

Connect the switch and cord to motor, true the disk by wrapping sandpaper on a block of wood, with the block sitting on the table hold it against the spinning disk. Remove the table, then the disk, glue 9" X 11" sandpaper to disk with white glue. Clamp as shown using scrap piece of plywood, trim sandpaper when dry. When sandpaper is worn out simply glue another sheet on top of it. Eventually you will have to strip all the layers off and start over.

Adhesive Disc Paper
Adhesive backed aluminum oxide.

Adhesive Disc Paper

Adhesive Disc Paper

About Electric Motors

Circle Sanding Jig

Sandpaper Disks

Circle Sanding Jig

This is a handy jig to smooth the edges of rough cut circles if they have an axle hole in the center.

Assemble the pieces as shown, glue the top strip as well as fastening it with screws, put a screw in the end of the sliding piece for a stop, without this sawdust may get between the two parts and affect the setting.

To set the jig, clamp it to the sander table, measuring from the face of the disk to the center of the dowel pin for radius of the circle. Slide the circle in and rotate it against sanding disk.