Type of motor to grind
Posted 08 December 2012 - 10:37 AM
I want to grind my 8" mirror with homemade grinding machine. So can you tell me what type of motor do i need and at what speed?
Can cooler motor will work?
your help will be appreciated
Posted 08 December 2012 - 12:27 PM
What do you mean by "cooler motor"? Air conditioner, refrigerator?
Posted 08 December 2012 - 12:28 PM
Posted 08 December 2012 - 01:15 PM
How much grinding do you plan to do? I think
the fastest,at least for me,has been the tub grinder.
The nice thing is you only need one motor and that is
for the spindle. The overarm is hand controlled no motor
needed, but you have to sit there while grinding. I put a
DC motor to drive spindle to simplify speed control but it could be done with step pulleys. The DC motor is controlled
by a bridge rectifier and variac. I recently modified the
tub grinder so I could use it as a fixed post grinder like
Gordon Waite's as seen on You Tube. So basically it is two
machines in one. As far as motors if you can afford the DC
motor I think that is best. If you are not going to grind
more than one or two mirrors the cost wouldn't be justified.
I've used as little as 1/4 HP could be even smaller if it has enough torque. As far as speed somewhere around 20 to
40 RPM especially for grinding. Too fast and you'll throw off most of the grit. Go on You-Tube there are plenty of
grinding/polishing machine examples that's where I got the
idea for fixed post grinding. The old timers mostly recommended under 5 rpm for the turn table and maybe
30 strokes a minute.
Also check out Burden's Surplus in Nebraska they sell all
kinds of neat stuff for building machines.
Hope this helps
Posted 08 December 2012 - 10:26 PM
The new ones I'm building for up to 28" use surplussed DC treadmill motors run by a Variac (AC auto-transfomer) feeding a 25 amp bridge diode for 0-40rpm at 50v or so... I figure it makes around 3/4 HP there. Put a filter cap on that DC unless you want the motor to hum.
Posted 09 December 2012 - 07:54 AM
Rather that starting with the motor you might want to decide on how to build the machine itself first...
Posted 09 December 2012 - 11:23 AM
Posted 09 December 2012 - 04:43 PM
Posted 10 December 2012 - 12:15 AM
Posted 10 December 2012 - 12:36 AM
Posted 10 December 2012 - 05:31 PM