Is there an easy way to add reverse to my drill press?

[rjnbaer939]

I'd like to add a forward/off/reserve type switch to a small drill press. The motor is a 1/3hp 120v 1phase with a single cap hump on the case. Is this doable? Thanks for any help!

[Arbo]

You need to determine if the motor is reversible. It should show a wiring diagram on the data plate for CW and CCW if it is. If so, add a drum switch and have at it.

[Daminer]

The motor should have a wiring diagram on it showing how to hook it up, IF it's possible to reverse direction.....Usually it involves swapping two connections in the motor's hookup box.....

In the past I've used a DPDT switch (double pole double throw switch to do this.....

Hope this helps, Jim

[Paul Alciatore]

You might want to study the quill first. If there are any threaded parts there, they may tend to come loose when reversed.

Ditto on the DPDT toggle. That's likely the easiest way to do it if the motor permits. Of course, it should not be switched while the motor is running. Sparks, smoke, loud noises. I guess that's why there are drum switches: they force you to go to off first. A DPDT with a "center off" position would do the same thing.

Paul A.

[ibewgypsie]

usually, blue and black exchange positions with connection on the black-hot white-neutral. (5&8? is blue-black) Hopefully it is on the nameplate.

it takes a two pole two position switch, or three position to stop it in the middle.

THAT IS, if the internal connections are not made up one direction.

I watched a real good electrician burn up a boiler feed pump.. He swapped two wires on the contactor, turned it on, it ran backwards, swapped them again, it ran backwards, swapped them again.. it smoked.. He didn't know single phase, only 3 phase.. he was so confused. I tried to explain to him but the "deer in the headlights look" ensued...

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David Cofer, Of:
Tunnel Hill, North Georgia

[rjnbaer939]

Well I poked around the motor case a bit, but there is no wiring diagram to be found. I guess the only additional bit of info I can throw out is that it says "induction motor"--in case that means anything special to anyone. As far as anything unthreading, it's not really a concern. Long story short is I am using this drill press powerhead as a very low speed drive on my lathe for threading. It works very well driving the stepped pulley on the main motor to a spindle speed of about 35rpm. I just need reverse so I can get back to my starting point w/o disenging the threading gears. Thanks for all the help so far.

[jcc3inc]

Dear Sir:

If you have one capacitor externally mounted on the motor, it likely is a capacitor-start motor; that is, the necessary phase shift to the starting winding is provided by having the capacitor in phase with the starting winding. What you need to do is to find the starting winding Beginning and End; reverse them and the motor will start running the opposite direction. This also works for strting windings which use only the higher resistance of the starting winding. Likely you have a starting centrifugal switch which opens the starting circuit once the motor gets going.

Regards,
Jack C.

[rotate]

Like Jack said, if you can access the two ends of the starter winding and reverse it, then the motor will spin the other way. Having said, that I believe UL/CSA no longer permits the manufacturers to have the two ends of the starter winding externally accessible (for safety reasons). If this is the case, then you can still reverse the direction of the spin by adding a large inductor in place of the capacitor which shifts the phase the other way. Another trick, although not advisable, is to remove the capacitor all togehter. When you start the motor, it will hum but not rotate. Using your hand, start the rotation in the direction that you want and it will spin in that direction happily all day. If the motor stalls, you'll have start it up again.

Check out this LINK



[This message has been edited by rotate (edited 09-03-2004).]

[bobodu]

Could you add a another little motor on a swing arm? Maybe a rubber wheel to rub on the drive pulley. Seen some mighty big oil field engines started this way.


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If nails are sold by the pound..why aren't screws sold by the turn?

[CCWKen]

Buzzing Motors, Rubber Wheel... ROFLMA.

35rpm... Hell, just add a crank!

[rjnbaer939]

Thanks to Jack C. and Rotate! I had to pull the motor apart and extend the internal connections from the start field to outside the cases, but it works like a charm. Now I just need to finish it up with a switch. Also, I do have a hand crank but using this setup has really spoiled me. It provides just as much control as hand cranking it but it is a heck of a lot faster and easier.