Reverse switch for drill press

[gard]

I had a bunch of broken screws that needed to be removed and thought I would try using left hand drill bits. Perfect excuse to set up the walker turner drill press for reverse. There is a small cover plate that says "to reverse rotation...interchange the connections". I looked around and found a DPDT toggle switch that would work if I added some jumpers but It would be pretty tight fitting under the existing cover. I found this 4 way light switch which the voltmeter confirmed is DPDT with internal jumpers. Perfect.



I adapted a small steel junction box to fit on the bottom of the motor. The drill press worked way better than a hand held drill and about 1/2 of the screws came right out with just the drill bit, the others with an easy out.

 

[rwdenney]

My old Delta drill press uses a standard old Dayton-style drum switch to allow forward-reverse operation, mounted over the spot where the original switch was located. When that was installed (back in the deeps of time), the installer ran a flexible conduit back to the motor.

Single-phase motors start one direction or the other based on the polarity of the starter winding, not the main windings. A reversing drum switch therefore provides contacts for the main windings and for the starter windings--but the instructions for wiring on the motor usually provide what you need to figure it out. Note that because the direction is set by the starter circuit, you can't change directions with the motor running (or even spinning). For auto-reversing tapping operations, one usually used a special apparatus in lieu of a standard chuck that provides the reverse direction when the tap's cutting load reaches a certain point (or something like that). Power-tapping without that requires timing, patience, favorable materials, and sharp taps .

But note that this drill press has an advantage--the special Jacobs chuck provided for this press locks to the Jacobs chuck taper using a threaded lock ring, and the spindle has that chuck taper machined into it, not the usual morse taper receiver. Reversing with unsecured tapered connections can cause chucks to pop out of tapers, so be careful.

Rick "has a set of left-handed bits for attacking broken screws" Denney

 

[Jake M]

But note that this drill press has an advantage--the special Jacobs chuck provided for this press locks to the Jacobs chuck taper using a threaded lock ring, and the spindle has that chuck taper machined into it, not the usual morse taper receiver.

You may aready know this, but if you or anybody who's got one of those and suspects the chuck is getting old, there's only one option left out there and it's been that way for a VERY long time. The price is skyrocketing at a pace that exceeds inflation and acts more like obsolescence. If yours is worn, or you want a spare, now'd be the time to keep an eye on the usual places for the best price you can find on one of those.

Jacobs 34-33C

Of course you can always use a "regular" JT33 chuck and give up the ring so you won't be "stranded", but that locking arrangement, but that's a dowgrade. That was expensive machining, it only got done on drill presses needed it...

 

[rwdenney]

You may aready know this, but if you or anybody who's got one of those and suspects the chuck is getting old, there's only one option left out there and it's been that way for a VERY long time. The price is skyrocketing at a pace that exceeds inflation and acts more like obsolescence. If yours is worn, or you want a spare, now'd be the time to keep an eye on the usual places for the best price you can find on one of those.

Jacobs 34-33C

Of course you can always use a "regular" JT33 chuck and give up the ring so you won't be "stranded", but that locking arrangement, but that's a dowgrade. That was expensive machining, it only got done on drill presses needed it...

You are absolutely right. The current Jacobs 34-33T chucks with locking collars are made overseas and apparently not what they once were, but they are the only game in town. At least they are from Jacobs with some level of support. My chuck is worn, so I just bought a new one before they disappear altogether.

Zoro has them for a little over a hundred bucks right now--about half of most other places--and I bought one through their ebay listing. That's expensive for a half-inch plain-bearing chuck, but with the locking collar it can be uses for lots of things that one would not do without the collar. I use might for light milling of small parts made of soft materials using a simple and very flexy old X-Y table. That works better than it has any right to, but attempting it with a taper-only chuck will be risky.

Rick "needs a mill" Denney

 

[gard]

I think you are correct about the wiring, if I had one of those drum switches laying around I would probably of used used it. Now I have one light switch to turn on the motor and the 4 way to select direction, It seems to work well.
Someone had added a set screw in the my arbor to clamp the MT in. I have not used it because I do have a small milling machine. I wonder if this is related to why my drill press arbor was bent by 0.035" when I got it.

 

[Jake M]

...if I had one of those drum switches laying around I would probably of used used it. Now I have one light switch to turn on the motor and the 4 way to select direction, It seems to work well.

I set my Powermatic up this way, kinda. I bought a proper "hockey stick" drum switch ('cause "available" and "in the right price range"), and set it up with that. Hadda take the motor apart and liberate some (crap) from the back of the connection board, as while this is a "reversable" motor, it was never marketed as such and there were literally two screws to hook up power... All that went well. BUT....

Given the habit of "all drill presses are the same", there were "mistakes". Months in, long after muscle memory should have been properly adjusted... I actually put the proper (not proper but they're all this way....), proper light switch back in the front of the head, and use the drum switch exactly as you're using your switch. Now I still can turn on the "master" and use the drum switch (safely and on listing) to start and stop the motor if I so choose, but I like the "master switch" better. Depending on you, as preferences differ, you might actually have a feature there, and not a drawback.

Zoro has them for a little over a hundred bucks right now--about half of most other places--and I bought one through their ebay listing.

I have NOT (nor could I ever in a lifetime) checked "everywhere", but that sounds like the bottom end of what I've found.

I use might for light milling of small parts made of soft materials using a simple and very flexy old X-Y table. That works better than it has any right to, but attempting it with a taper-only chuck will be risky.

Yeah, my Powermatic is tight, but it's not that tight..... But, while milling is NOT on "proper" list for a drill press, doing router work with it (Real router work, not portable router work), that WAS on the list of approved things to do. And drum sanders. That's my favorite way to liberate a captive chuck. Then there's those old circle cutters with the single point cutter. Or the "Safe-T-Planers. Ever seen those? safer than what? How the (heck) did you plane with a drill press when it was dangerous? Good grief times were different. That thing scares the heck out of every time I use it. I act accordingly, and I love it. It actually works. But it'll separate an MT2 chuck more efficiently than wedges will, and will give a drift key a run for it's money...

Rick "needs a mill" Denney

 

[gard]

Self feeding ship auger drill bit will also pull out the taper if you try to feed slowly. Also milling cutters with too much spiral. I have used a little bit of the removable grade locktite on the Morse tapers with good luck.