T.R | Title | User | Personal Name | Date | Lines |
---|
2107.1 | problems with rheostat | FIEVEL::FILGATE | Bruce Filgate SHR3-2/W4 237-6452 | Fri Feb 28 1997 17:35 | 17 |
|
Because the drill press has an induction motor, the rheostat will only
reduce the torque. The reduced torque, along with the drag associated
with the pressure on the bit, will dictate the speed of the bit. If the
drag on the bit is constant, it might be possible to control the speed
`close enough'.
I mounted a pair of pillow blocks and a jackshaft on a plate pinched
between the motor and the drill press. After turning the motor upside
down and reversing its direction it drives the bottom end of the vertical
jack shaft with pulleys and a belt. The top end of the jack shaft gets
the original stepped pulley from the motor installed on it and a
someone longer than original belt is used to power the press.
good luck with which ever,
Bruce
|
2107.2 | | HELIX::WELLCOME | Steve Wellcome SHR3-1/C22 Pole A22 | Mon Mar 03 1997 09:58 | 14 |
| re: .0
You've almost certainly got the wrong kind of motor for that to work.
Routers and such have "universal" motors, but the drill press most
likely does not. Its speed is tied to the line frequency, so to change
the speed electrically you have to vary the line frequency from 60 Hz
to something else. While there is equipment available to do this,
the last time I checked the cost was in the $500 range, probably a
bit much.
Your best bet is probably to vary the pulley sizes, add a new
countershaft, or get a slower-speed motor (you can get 1140 rpm
motors, but they're a bit expensive too). Or perhaps a gearhead
motor.
|
2107.3 | | jammer.zko.dec.com::Jack | Marty Jack | Mon Mar 03 1997 10:44 | 5 |
| Also, if you are talking about the "Bench" drill press,
make sure that the quill stroke is adequate for your needs.
It is only about 1 1/2". I regret having invested in the
12" and should have gone for the 14", which has a quill
stroke in the 3 1/2" range.
|
2107.4 | Delta 14" likely | AIAG::MILLER | | Mon Mar 03 1997 13:34 | 8 |
|
Thanks to all for the feedback. It seems very consistent with
additional advice received over the weekend. Appears the Delta
14 inch at Home Depot for, ouch, $287 is the best way to go.
regards,
Walt
|