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This interesting-looking old drill press posted to the Toolmonger photo pool has us scratching our collective noggins. It’s obviously a belt-powered drill press of some sort but we have no idea what its original setup would have looked like.

The stock plate doesn’t have a hole in it, which to me says metalwork — though I suppose that’s not always true. The whole thing looks like it’s built for fine adjustment with the knobs at the spindle shaft, but the wheels at the rear are a bit of a question for me. Is the belt supposed to loop through them or is it for a second belt that controls the height?

We always find this type of shop mystery thought-provoking. We hope reader Ghb624 finds out how this rig is meant to be set up and what its original purpose was. Let us know what you think in comments.

Toolmonger Photo Pool [Flickr]

 

15 Responses to Flickr Pool: Drill Press Mystery

  1. Drillpress says:

    Looks to me like the motor would be under the table, and the belt would come up over the rear wheels, around the spindle, and back down.

  2. melee says:

    Hard to tell without actually handling the thing, but it looks like the drive belt runs over one of the pair of rear pulleys (which I would think are linked) from a table-mounted (or, if really old, overhead) drive system; this would cause the pulley on the other side to spin, and it would be attached to the spindle pulley with a 90 degree twisted belt.

    I presume the table moves toward the bit via that lever on the bottom, so you’d definitely want to clamp the workpiece. Judging by the size of the pulleys, and assuming that it’s an electric motor driving it, looks like it’d be wood speed, but I suppose you could easily change that with a different drive pulley.

    It would be a lot easier to say, obviously, if one could play with the mechanisms.

  3. melee says:

    …if the rear pulleys are free-spinning, then it’s probably a one-belt setup, with it going up from the table to the left, to the spindle, to the right, and then down again to the motor. The alignment of the rear wheels vs the spindle wheels doesn’t look quite right for that, but maybe it’s just the angle of the photo; the angle from the top of the rear pulleys to the middle of the spindle isn’t entirely impossible.

  4. Charlie says:

    My first thought was an overhead belt, but looking at the picture it looks that the tops of the back pulleys are in plane with the front pulley, so the belt would be coming from below. Based on the lack of mounts on the base for a motor, it probably had drive power coming from an external shaft and belt system.

  5. Jim says:

    My dad has one just like this except it uses a flat leather belt for drive and has stepped pulleys for speed adjustment.

    The knobs on the spindle are grease cups. You fill them with grease, and screw them on. Every so often, you give each one a quarter turn which squeezes a little more grease between the spindle and journal bearing.

    The spindle does not move up and down, but the table moves via the lever.

    And yes, the motor would be mounted independently behind or under the machine (or it would be connected to shop drive system).

    Without having any knowledge of how fast the motor or shaft input speed was, it’s hard to say how fast this thing was meant to spin. Either way, it was probably used to drill blind holes since there’s no clearance hole in the table.

  6. Dan says:

    Corvairs used a similar twisting-belt setup. Corvairs also tossed belts at an ignominious rate.

  7. Carroll Lam says:

    I posted a picture of a drill press that uses a similar belt drive concept. These were first-year mechanical engineering foundry course projects at Texas A&M.

  8. William Ricker says:

    I inherited a quite similar twisted v-belt table-standing drill-press from my Great Uncle, an Edwardian electrical engineer. Mine had the electrical motor bench-mounted behind, now mounted to a common plywood base. The suggestion of through-holes to under-table mount is good, I have seen that on belt-driven grinders, but that wasn’t how I found it. Mine has three-speed head and a bit more guard there, and the standard hole-and-slot stock table, not the mystery solid table .

    I would suggest lack of a hole in stock table means its original purchaser intended it solely for controled-depth blind-holes, either for tapping in metal or pegging in wood, eg cribbage boards. Or drill halfway reaming a pilot hole, and flip, to avoid ripping out the back.

  9. DocN says:

    It’s what’s known as a “sensitive” drill press- note the table moves up and down via a small lever, while the quill remains fixed.

    It’s a production machine, meant to be set up for a specific hole of a specific depth, using a small jig or fixture. An old factory would have a row of these- one would spot drill, the next would drill to size, the next might counterbore or ream, and so on. That’s the way they did it before CNC- instead of one machine making multiple cuts automatically, as we have now, each machine in a factory would just make a single cut each, using jigs and stops, with an individual part sometimes passing through dozens or even hundreds of separate machines.

    The belts were indeed set up like the delta that Russell linked, either to a small stub-lineshaft or to an individual electric motor.

    And those quill bearing cups don’t use grease, they use a heavy “vacuum oil”. A bit heavier than motor oil, but not quite as heavy as differential/gear oil. Don’t put grease in ’em, that’s a good way to kill a sleeve/babbitt bearing.

    Doc.

  10. tmib_seattle says:

    Here’s one that’s been restored, with the leather belt:

    http://www.owwm.com/photoindex/detail.aspx?id=3421

    And here’s one I saw on Craigslist:
    http://seattle.craigslist.org/see/tls/1237199645.html

    –TMIB

  11. Brau says:

    It could even be made into a cordless drill press! Just run the belt through the tabletop, down to a foot treadle and Viola!

  12. Russ says:

    This drill can be mounted on a lathe.

    A pulley mounted in the chuck can drive a belt that runs up to the rear wheel the drives the drill chuck.

    Russ

  13. Scott Richards A&M Bsme 1981 says:

    Actually 2nd year classes for Bsme majors, ET209&210 I think. Engineering Technology courses aka ‘Easy Trucking’ for us Mechanical Engineers. I could only get into the first class circa 1979? I can look up the course numbers. Always wanted one just for display. Guy at Swri had one but would not sell.

  14. Fletcher Pool says:

    We made them in the Engineering Department shop courses at Texas A&M College covering: 1. “Foundry Pattern Making”, 2.”Foundry Casting”, and 3. “Machine Shop”.

    The base is supposed to be behind the spindle and the adjustable stock plate.

    The electric motor was bolted to the base with a long V-belt run under the motor pulley, up over the two pulleys behind the spindle, and around a two-step spindle pulley on top of the spindle.

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