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Build a surface sander that's every bit as smooth on your budget as it is on a board.

Chances are, if you're only an occasional woodworker, you'll never really need a surface sander. But if you do a fair amount of woodcrafting, this 12" homebuilt tool will make a nice addition to your shop.

The framework is made of 16-gauge (about .070"), 1"-square tubular steel stock . . . which can be replaced with a heavier-walled material if necessary. The table is a 3'-long section of 3/4" plywood cut from a cabinet door; that 7-ply birch panel was an excellent choice because it's resistant to warp and has an extremely smooth finish. The sanding drum and feed rollers were fabricated from hardwood disks and dowels, respectively. The drum is spiral-wrapped with 1" aluminum oxide machinist's cloth held with adhesive, and the rollers are covered with 1-1/2" reinforced rubber hose sections.

To keep the design uncomplicated, the drum is powered, but the feed rollers operate manually with a hand crank. The infeed and outfeed rollers turn in unison, since they're connected with a V-belt. As you might imagine, drum sanding requires appreciable horsepower, even for a benchtop unit like this. Our sander performed satisfactorily coupled to a 1-HP, 1,750-RPM capacitor-start motor, though a split-phase type would work just as well because starting torque requirements aren't that critical. By using a 5" drive pulley, we were able to achieve about 3,000 RPM at the sanding drum . . . the equivalent of 3,450 surface feet of sanding per minute.

The sander's depth of cut is adjusted by raising or lowering the table, which is mounted on a bed hinged to the base to form a parallelogram. A length of threaded rod fastened between two clevis shafts on the base and ta ble bed sets the table height. Any irregularities in the surface of the workpiece are taken up by spring-loaded pinion guides, which allow the rollers' axle shafts to rise up slightly under pressure from below.

POINTS IN PARTICULAR

We've provided both an exploded illustration identifying the machine's parts and dimensioned plan views to aid you in putting together your own sander. Furthermore, we've gleaned a few tips from our research shop that should help you make the transition from paper to project as pleasant as possible.