gary thomann
11-19-2011, 5:15 PM
A small drill press is a wonderful tool except for the table height adjustment; about the time you get everything set up you see the height is not right. When you turn the crank the table swings back and forth and ruins the setup. I have seen a couple of posts in forums about using a motor to raise the table. My brother even told me about somebody who connected a cordless drill to the crank.
My motorized lift uses a windshield wiper motor I got from Monster Guts; price right now on the motor is $16. I used a piece of aluminum to mount it under the table. The enclosed two jpegs show the mounting; I took the table off and laid it upside down for the photos. You can see I didn’t do a very good job on the aluminum; I was just kind of experimenting when I started and the mount was one of the first things I made.
The drive uses a timing belt and two pulleys. One pulley is mounted where the crank arm was connected and the other on the shaft of the wiper motor. Belt tightness can be adjusted by moving the aluminum mount. To run the motor I use a momentary double pole double throw switch; I got it at All electronics for about $3.50 although of course there was some shipping cost also. For a power supply I am using a charger that came with one of my previous cameras; it is listed as 12 V 3 A and seems to have enough power.
The only real problem is the shaft on the wiper motor, the connector from Hell. It has a tapered friction fitting with a 6 x 1 mm threaded shaft sticking out from the taper. Nothing standard about it. I spent so much time on this I drew a picture which is shown in the other drawing. Basically I cut about a 1” length of 5/8” aluminum rod and then drilled it out and tapered it so it more or less matches the fitting on the motor. A barrel bolt is used to hold it on. The advantage of using the piece of aluminum rod is that when you do something wrong and ruin the fit you just cut another piece and start again. The hole in the pulley is drilled out to 5/8” so it fits over the rod. I found a source for 6 mm barrel bolts but didn’t get them; in my pile of old bike parts I found a brake boss from a previous mountain bike that works. The brake boss is the strange looking thing you see sticking out from the pulley. A real barrel bolt would be prettier.
I have been using this setup for about a year, and I smile every time I adjust the height. The motor is kind of cheap and some times you have to flick the switch a couple of times to get the motor to start but that is no real problem. Every drill press should have such an adjustment; if it was built in only a few dollars would be added to the tool cost. If you want to use a wiper motor to drive something you can try my fitting method.
213272213273213274
My motorized lift uses a windshield wiper motor I got from Monster Guts; price right now on the motor is $16. I used a piece of aluminum to mount it under the table. The enclosed two jpegs show the mounting; I took the table off and laid it upside down for the photos. You can see I didn’t do a very good job on the aluminum; I was just kind of experimenting when I started and the mount was one of the first things I made.
The drive uses a timing belt and two pulleys. One pulley is mounted where the crank arm was connected and the other on the shaft of the wiper motor. Belt tightness can be adjusted by moving the aluminum mount. To run the motor I use a momentary double pole double throw switch; I got it at All electronics for about $3.50 although of course there was some shipping cost also. For a power supply I am using a charger that came with one of my previous cameras; it is listed as 12 V 3 A and seems to have enough power.
The only real problem is the shaft on the wiper motor, the connector from Hell. It has a tapered friction fitting with a 6 x 1 mm threaded shaft sticking out from the taper. Nothing standard about it. I spent so much time on this I drew a picture which is shown in the other drawing. Basically I cut about a 1” length of 5/8” aluminum rod and then drilled it out and tapered it so it more or less matches the fitting on the motor. A barrel bolt is used to hold it on. The advantage of using the piece of aluminum rod is that when you do something wrong and ruin the fit you just cut another piece and start again. The hole in the pulley is drilled out to 5/8” so it fits over the rod. I found a source for 6 mm barrel bolts but didn’t get them; in my pile of old bike parts I found a brake boss from a previous mountain bike that works. The brake boss is the strange looking thing you see sticking out from the pulley. A real barrel bolt would be prettier.
I have been using this setup for about a year, and I smile every time I adjust the height. The motor is kind of cheap and some times you have to flick the switch a couple of times to get the motor to start but that is no real problem. Every drill press should have such an adjustment; if it was built in only a few dollars would be added to the tool cost. If you want to use a wiper motor to drive something you can try my fitting method.
213272213273213274