You've seen those Baldor-brand buffing motors in the tool catalogs. You know the ones, with their long shafts and expensive price tags, but you just can't quite justify the expenditure. Neither can we. So we decided to build our own. And our home-made buffing wheels work just as well as the professional kind, so here's how we did it...
What? That's right, start driving through your neighborhood on "trash day," looking for a used clothes dryer or forced-air furnace. (No, we haven't lost our minds, we need to find a good electric motor. Nine times out of ten, the motor in a broken clothes dryer or furnace works fine and is just about the right size — 1/3rd to 1/2 horsepower — to power a buffing wheel.) You can also go to the city dump or landfill to find motors. If you do that, pick up several. While you're at it, look for an electric range too! You'll want it for powder coating; and don't worry, no matter how bad the burners look the oven section will work. We'll wait for you to load all your new-found treasures...
Okay, we have the motor. Before going any further we need to check out the motor to see if it operates properly and to see in which direction it turns. Don't be confused by multiple wire connections. The manufacturer of the motor might have used various connections to alter speed and direction of rotation. All motors have a plate or tag that lists input voltage, current draw (or total wattage), speed (either 1725 or 3450 rpm) and horsepower (one horsepower equals 746 watts, by the way).
Look carefully at the stampings on the motor's connection board (inside its electrical input housing). These boards are marked most frequently with such designations as "line 1", "line 2", "comm.," etc. Also, some motors have capacitors mounted on their housings and these have similar markings. Whatever you have, experiment a little until you find the correct connections to make it work. Connect your cord to these points but don't forget that you will run the "hot" lead through a switch.
There are two ways to go about this. We can simply mount a buffing wheel on the motor's shaft; or we can power an arbor that will drive two buffing wheels that are set apart. The advantage of doing the latter is that you have a selection of wheels, and the greater number of differing wheels (materials, diameters, etc.) the greater the flexibility of a buffing system. Also, the farther apart the wheels are, the more room there is to maneuver the item being buffed.
We will show you how to do both kinds, since we have a total of 6 buffing wheels here in the Second Chance Garage. First, the motor-mounted wheel:
Your motor's output shaft will almost certainly be 1/2 inch in diameter and smooth: that is, not threaded (if it's threaded, the next step is eliminated). Measure the shaft diameter to be sure, then go to the hardware store and buy a shaft adapter. These adapters are sold everywhere. They are threaded at one end, fitted with a nut and, usually, two big washers. The other end is larger and drilled out so that it slides over the motor's shaft. Allen screws or other fasteners hold them securely onto the motor's shaft.
Motor, shaft adapter, arbor bearings and shaft, plus pully and belt.
Once the adapter is fitted to the motor, mount the buffing wheel (use more than one for more thickness) with the washers and nut. Cut some thick wood into pieces that are as wide as the motor's footpad and long enough to extend a little bit out over the edge of the workbench, so that you will have lots of room to maneuver items around the wheel.
Screw or bolt down the motor and wire it through a switch, making sure the switch is located far enough away to prevent interference, but close enough to shut off the motor when/if things get tangled.
There's only one potential disadvantage to mounting buffing wheels directly to motors and that's the speed of rotation. Most motors you find rotate at 1725 rpm, while the "ideal" speed is 3450 rpm (virtually all AC electric motors turn at one or the other speed). Your buffing wheel will work fine, but most tasks will take a little longer and you'll have to put in a little more elbow grease.
If you have a bearing-mounted arbor that can be turned by a belt-driven pulley, all the better! We have two types here, a single casting with twin bearings and two separate bearing mounts. It's always better to use the single casting because unless the two separate bearing holders are perfectly aligned when mounted, the shaft will bind and heat up or stall the motor. To find these items, look through your yellow pages for bearing/power transmission specialty wholesalers. They can find what you want. The cost will typically be less than $20.
Once you have your arbor, mount it securely on solid wood where it will have the greatest maneuvering-room. Before this, however, you've chosen a proper set of pulleys (to achieve 3450 rpm, remember?) and a belt long enough to reach the location of the motor (it's best to set the motor at least one foot behind the arbor so it won't get in the way).
All set? Now all you have to do is mount the motor in such a way that it can be moved to tighten the belt. The footpad on most motors has elongated mounting slots, so we install the belt on the pulleys and push the motor back until the belt is snug, then mark the position. From there we drill holes for mounting bolts, leaving plenty of space for the motor's slots. Once everything is in place we just wedge a screwdriver into the wood next to the footpad and pry the motor back until the belt is nice and tight, then crank down the mounting bolts and nuts.
Mounted motor and arbor, with a nice long belt. This particular set of wheels is 10-inches in diameter. One wheel is a hard sisal wheel used for rough cutting and taking off rust and scale quickly. The other wheel is a loose-weave finishing wheel.