View Full Version : 12 Volt Speed Control??

07-15-2007, 08:46 AM
I wish to find a speed control that will alow me to control my punchmaster spin index while grinding down diameters on my new ( Old Norton) surface Grinder) I was thinking of using a Windshield Wiper motoer and a speed control for it) What do you think of this? Is ity a Feasable deal?? Thanx Mike Oh where can one buy one ? Thanx mike

Forrest Addy
07-15-2007, 09:40 AM
How about here?

http://cgi.ebay.com/New-DC-Motor-Speed-Control-Fully-Assembled-Module_W0QQitemZ170128647206QQihZ007QQcategoryZ105 793QQrdZ1QQcmdZViewItem

and here?

http://cgi.ebay.com/DC-12-VOLT-FASCO-MOTOR-BLOWER-FAN-37W-ELECTRIC_W0QQitemZ200127553485QQihZ010QQcategoryZ7 1400QQrdZ1QQcmdZViewItem

You gotta watch the physics of home brew motor projects. Getting the motor to drive the load at the right RPM is often the deal breaker. Windshield wiper motors run up to about 150 RPM. Pretty slow for small diameter work. OD grinder work optimizes at about 150 surface feet per minite. Do the math and go from there.

07-15-2007, 01:19 PM
Yes a spindle speed of up tp 300 RPM should do it. Just like the expensive suburban motor drive. Im thinking the wheelchair motor is the way to go with the speed controller. Thanx for the info Forrest. Mike

Duct Taper
07-16-2007, 12:13 AM
Try www.surpluscenter.com for motors. I have bought several things from them and am satisfied.

07-16-2007, 05:17 AM
Nice bunchah stuff.

Paul Alciatore
07-16-2007, 09:02 AM
For a light duty application like turning a workpiece while grinding, you could probably get by with a simple rheostat for the speed control. Just make sure it will take the current. If I remember correctly, the highest power disipation in the rheostat is at the half voltage point: 6 Volts in each of the rheostat and the motor so figure the wattage of the rheostat at that point and add a safety factor.

And yes I am well aware of the advantages of electronic speed control, but for such a simple job it may not be needed.