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  • drill press

    Here's a few pix of my latest project. This is from the headstock side, and has a cover removed to show internal details. You can see the wiring on the armature and the brush holder assembly. The sickly green colored thing is the flux containment ring that surrounds the motor magnet can.

    The side boxes are where the vertical slides are hidden.
    The head is shown tilted to the angle that the downfeed handles needed. That was the first job this thing was put to. The head can be tilted from about 20 degrees left of vertical, to about 20 degrees below horizontal. I have about 2 1/2 inches of down travel before the ball bearing slides run out. Check those out- they look suspiciously like drawer slides-
    There are no gears or belts- it's direct drive.

    Looking at it from the other side- this shows one cover on and some wires sticking out. You can see the second downfeed handle here. The bolts will be replaced with authentic looking handles. As you can see, there are some details that are yet to be taken care of. The vertical post sticking out the top has a toothed rack within it, and obviously there's a pinion engaging it for downfeed. Oh, and ignore that bright white spot on the side of the lathe chuck. I think I might have used it to show the zero mark on the degree disc that's behind the chuck. My markings have worn off and now I need to stamp them onto the disc properly. (and finish the engagement lever for the pin that indexes the spindle via the disc)


    This shows the mounting base that clamps to the lathe bed. There are two bolts that draw up a pair of plates from below. Just to the right of the base is a pin sticking up. This pin rotates both plates together to allow the base to come straight up off the lathe. Push this pin forward, the plates allow removal of the base. Pull the pin towards you, the plates hook under the ways, then the two bolts are turned about half a turn each to tighten. The base is very solidly held to the ways.
    When I remove the base, it can set down on any flat surface without the mating surfaces touching anything. I can see that I'll have to be careful about keeping the ways clean whenever I need to slide the base to position it. It will mostly be put in one position and stay there while drilling is being done, so maybe it won't be a big deal. Still, I may fab some covers to keep swarf off the ways.


    I'll solicit some advice- in the vertical mode, the weight of the head would normally require some spring tension to keep it elevated- nothing unusual for a drill press. In the horizontal mode, there is no need for that. I could either spring load it or not. If I don't, I'll have to have some kind of slip clutch that would keep the head in any position that I put it. I would like to be able to turn the feed handles to position the head, then have it stay there rather than automatically retract, as would normally be the case (with the spring return), so I'm leaning toward the slip clutch idea. Any thoughts?
    Last edited by darryl; 05-10-2007, 03:52 AM.
    I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

  • #2
    Nice

    Should be handy if youre drilling lots of holes in parts on youre lathe. Nice Job.

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    • #3
      Ok. This proves you are as crazy as I am. What's it for?

      I have some vague ideas about the counter balance problem but without a better idea of the exact configuration can only make a guess. Some sort of spring-cable actuator acting via a cam/lever that changes the applied effort when the head is rotated comes to mind.
      Free software for calculating bolt circles and similar: Click Here

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      • #4
        You know that if you had mill and a dividing head you'd be finished by now, right?
        LOL
        All smarta$$ remarks aside... I've been thinking that a way to mount something like that might be usefull once in while.

        BUT...What I've really been contemplating is yanking an old D1-4 spindle nose off a beat up lathe I have and makeing an adaptor that will mount it to my dividing head. Then I can pop a chuck off the lathe and drop it onto the dividing head and back to the lathe again.
        Now that would be some sweet versitility!
        Ignorance is curable through education.

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        • #5
          I must be as crazy as they come, even if I don't take the cake. Usually a need arises more than once or twice, then something twigs and another project is born. This one combined a couple of hobby activities of mine, so it's not like I wasted time building something that'll only get used once. Anytime I turn something and need a cross hole, or a laid out pattern on the face of something, this will allow me to do it without taking the piece out of the chuck until it's done. It will open the door to do some things that I wouldn't have done otherwise.

          I looked at a combo machine the other day (not with any intent of buying one) and everywhere I looked on it, there was a compromise made. I could see how it would be far less useful to me than this current setup. The only benefit I could see to one of those, besides space saving where that is paramount, is that it could turn a larger diameter.

          Anyway, I figured what I might do for the downfeed is utilize a spring, but have it take up only about half of the weight of the head. Then I'll put a friction pad with adjustment to bear against the side of the downfeed rack. That way I can set it on the fly and get the best of both. In vertical mode, the friction pad won't need that much pressure to keep the head from moving, and in horizontal mode I'll need to use positive pressure to move the head, but not so much that it's annoying. The friction adjustment will be able to lock the head in position without needing to be too tight.

          One other thing- I'd like to paint the covers at least so it's not all grey metals looking. I suppose in keeping with tradition I should use green Time to look in the paint cabinet.
          I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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          • #6
            Cool

            I tend to JIC my designs with "needed" features that I never use. For this design, I would have a "multi-depth stop with fine adjustment screw", a "handcrank" so I could tap the hole after drilling, and a way to use "left hand twist" drills under power (because I never break taps). Then after collecting all the parts to make it, I would keep using a cordless drill and "eyeballing" the angles...

            What did you steal that motor from?
            What is the motor rpm, and is it variable speed?
            Can it be used as a grinder?
            Today I will gladly share my experience and advice, for there no sweeter words than "I told you so."

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            • #7
              Funny thing- I was just thinking about putting a depth stop on it while going online to read here. I'll be drilling holes by hand to instal that, and I was thinking about how to go about it without getting chips on the slides, which are now greased. I have painted a few parts and fixed a switch and proper power cord to it- not much left now- a couple felt wipers for the vertical rods-

              The first job I did with it was to drill and tap the holes for the typical drill press type handles. I just grabbed the chuck and turned it to do the tapping. Works pretty well because the downfeed is so smooth and it's easy to put a suitable amount of pressure on the tap as it starts in. There was plenty of room for my hand. Now that I have the feed handles on and the spring return done, it should be even easier to tap with it. I did put a lever on the side which adjusts a friction so I can lock the head in place, or dial in whatever restriction I want to its travel.

              What did I steal the motor from? The motor was originally part of a GM anti-skid braking system. I actually took two of these apart so I could make up a new armature with about 1 1/2 times the number of laminations on it. I used the magnets from one motor only, but did also instal an extral layer of sheet metal around the outside to increase the internal flux. I made a spindle from some misery metal to include the chuck on one end, the bearings, comm, lamination stack- wound 528 turns of wire on it, epoxied, made up a new brush holder- As you can tell, this motor as it is now is not available anywhere.

              It turns about 700 rpms per 10 volts, drawing just under an amp with no load. Loaded it will pull over 10 amps with 15 volts, and would pull 20 amps with 30 volts, etc. I nearly burnt my hand on the chuck while trying to get some idea of how much torque can be had.

              Reversable- easy. It's a dc motor, so all I would have to do it swap the red and black banana plugs on the power supply. I can dial in anything from about 3 volts to about 80 volts, so potentially I have about 6000 rpm as a top speed. With an electronically regulated motor speed control, I'd have full torque down to pretty much zero rpm, but I'd probably transfer the workpiece to the mill if I needed a slow speed with a larger bit. This chuck is a 3/8, and I don't think I'll have a problem drilling that size hole. Most of the holes I would be drilling are smaller anyway. If I need holes beyond the capacity of this press, I'll make pilot holes with this, then drill em out on a larger machine.
              As a grinder- I suppose it would work, but I wouldn't want to get swarf in the slides. They are shielded, but not sealed.

              One drawback to this design is that to change the angle more than 30 degrees I have to remove two socket head screws and re-insert them into other tapped holes. A long ball end hex tool would make this quicker and easier. I have one, but up to now I've been afraid to get it out of the case. I didn't want to find out that they are crap. (foreign manufacture, cheap) Turns out they are decent, so there I go. I have the tool for this.
              I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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              • #8
                Thanks for the info

                I'm not an electrical genius, but that motor "stood out". It also gives me a "scale" of the drill press. I wasn't sure if it was just a shiny "portaline" clone with a gutted Dremel, or something larger.
                Today I will gladly share my experience and advice, for there no sweeter words than "I told you so."

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                • #9
                  Couple more pix- At this point I've made the handles and added a power cord and switch, depth stop, friction adjustment, and the spring. The brass disc behind the brass handle part is the spring adjustment. It can be positioned in 1/6 of a turn increments. This side of the handle is a small lever with a ball on it- that's the friction adj. The blue plastic piece is the depth stop adj. You can just see the switch at the bottom of the pic.


                  Here the head is horizontal and set up for face drilling at a radius of about 1/2 inch.



                  TECKSHOP, the motor is considerably more substantial than a dremel, being about 3 inches across and about 5 inches long if measured as a separate piece. It's a four pole with four brushes. I did not balance the armature and as a result there's some vibration at higher speeds. Not really noticeable below about 3000 rpm.

                  A friend came over today and looked at this machine. After he realized that it could drill a hole precisely centered in whatever was in the chuck, he came up with the classic problem people have when trying to drill a hole crosswise through something round (pipe or rod). He went through quite an animation trying to show me how his hand drilled holes went off kilter. I guess you had to be here, it was entertaining
                  Last edited by darryl; 05-15-2007, 03:12 AM.
                  I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

                  Comment


                  • #10
                    Neat,putting together your own motor,that's not crazy,it's just hardcore!

                    How rigid is it?
                    I just need one more tool,just one!

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                    • #11
                      Aw, and I liked the idea of being crazy- but hardcore will do.

                      How rigid is it- well, there's no side play and I can't see any flexing motion as I apply side forces. Better than I expected. What I did was to build up the vertical rods first, then the clamp blocks that slide on the rods. Then add the pivoting pieces with the drawer slide pieces on them. With the inner slide parts in place (balls and all) I then measured the distance left between. I built the motor carrier to that dimension, which then shrank a small amount as I cleaned up the cuts. Duriing assembly, I shimmed a total of 30 thou to do two things- center the axis with the lathe's axis, and to preload the slides. They roll smoothly without any discernable play or flex. Things don't always work out as well as this did, so I'm pleased with the results.

                      I robbed the chuck off a cordless drill a friend gave me. At one point he had bought a better chuck for it, and that's what he gave me with it. I read somewhere recently that chucks are made in three general places- cheap chucks- china, better ones, usa, best ones, germany. This is the usa one, and it runs true. I did check out all my chucks, and this is the best 3/8 one I have. It probably helps that I machined the spindle to give a reference surface to match the chuck, and a shoulder turned true. At the same time I made the threaded end an insert, so it was slightly floating. This lets the chuck put those threads where it wanted as it's run up to the shoulder. I epoxied and pinned the threaded stub so it became an integral part of the spindle. One thing I won't know is whether another chuck would fit on the spindle- it's possible that the reference surface could be too large for a different chuck. Won't matter to me anyway. This chuck is good and it grips well.

                      There's still a few things to attend to. I need washers under some socket head screws so the screw heads don't bite into the aluminum- I need to make the felt washers that will keep crap out of the side clamps- I need to add a locating pin to speed up the adjustment for true vertical and true horizontal.

                      I know I'm blathering on a bit, but I thought maybe someone could use some of the techniques I used on one of their projects.
                      I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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                      • #12
                        I know I'm blathering on a bit, but I thought maybe someone could use some of the tec

                        Thats ok, just send me the prototype for testing.
                        Today I will gladly share my experience and advice, for there no sweeter words than "I told you so."

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