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  • High speed drill press

    I'm the guy that recently started a thread on a mini lathe. I'll also looking for a high-speed drill press. This is something that I won't have to use very often, but it would come in very handy at those times when I would need it. I have the option of getting a slightly rusted Dumore 37-021 for $340. This seems pretty good, but I'd rather not have to spend anywhere near this amount.
    There are cheap high-speed drill presses on ebay, but I don't know if they'd be fast enough. The $65 ones seem to top out at 8500 rpm. The "true" high-speeders seem to be twice this. Another big concern is run out with these. Having accurate travel isn't that much of an issue, since I can use a sensitive bit.
    An interesting option that I heard described by someone else was to get a solid mounting platform, and mount a shaft with two bearings. At the bottom of this, a hiqh-quality sensitive chuck was mounted. Somewhere further up, a pulley was mounted on the shaft. The pulley was run by a belt to a dremel that was mounted (somehow) nearby. The beauty of this solution is that a dremel, which I already have, can be used to generate the necessary speed of the press. What the dremel lacks, precision, can be addressed by transferring the rotation to a stable spindle.
    As a variation on the "dremel" idea, it's now occurring to me that I could get used lathe headstock, mount it vertically, and do the same thing as I would do with a shaft mounted on two bearings. This seems like a preferable idea in some ways, since I currently have no way of making the double bearing shaft. This solution would cost about $75 for the headstock, so it might be the most efficient way to go.

    So, going the "right" way, I'd be paying:
    $340 for the Dumore and $180 for a sensitive chuck. The "wrong" way would save me $265, a big chunk of change.

    Any ideas? Thanks.

  • #2
    I have a dremel that I mounted in one of those old cheap gizmos that they used to sell to mount a regular power drill in to make it (low) budget drillpress. It was a cheap Sears thing I think, probably flea market find. I undid a turn or two of the return spring to give it a lighter feel to the downfeed. I set it up mostly to drill stuff like circuit boards and some small jewelry type stuff on the cheap. I already had the Dremel so I probably had under 10 bucks in the whole deal.

    I did it as an experiment and found it worked surprisingly well for what it was and served my purpose effectively for a long time. Might have a photo of it someplace. I don't know exactly what your needs are, but if they are fairly modest, this can work better than you might guess. I was mildly surprised myself. Just some food for thought. Might be worth an experiment.

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    • #3
      Some of the small sensitive drill presses have the spindle stationary and the table is raised up with a lever. This might be simpler than making the motor and spindle go up and down, neither is very difficult though.

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      • #4
        As for the first idea, I tried something sort of like this. I bought a drill press made for a dremel that really didn't work out. There was a bit of run out with the bit, and the lever offered no feel at all. As a result, I just broke bits. The sensitive table is an interesting idea. My concern with this idea is that it might not be sensitive enough. If it is, I'll still have the runout issue.

        I really was hoping that this cheap way would work. It seemed so easy, but it just didn't work.

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        • #5
          Originally posted by music321 View Post
          As for the first idea, I tried something sort of like this. I bought a drill press made for a dremel that really didn't work out. There was a bit of run out with the bit, and the lever offered no feel at all. As a result, I just broke bits. The sensitive table is an interesting idea. My concern with this idea is that it might not be sensitive enough.
          The dumore speeders are excellent, but that seems pricey for one without a chuck. I used one for a long time, just hold it in the drill press and use a DIY sensitive table shown below. This is from a design from the mag, and works really well. I've added a few high speed drill press to the stable over the years, the shi-shi'st being a Servo, but that little sensitive table is hard to beat. The guys will be tired of those pics I've posted them so many times, but its really worth having one and is a very simple project....it makes those unbalanced and heavy commercial tables or those things that go in the chuck seem crude.

          You maybe well ahead of me on this, but its a frequent thing where newer guys think that need high speed for drilling small holes. Its just not so, it makes it faster and is nice, but its not necessarily. Sensitivity and concentricity are way more important. The misconception is a product of applying the cutting speed formula, forgetting that its a formula to maximize removal rates, not a requirement of good cutting action. In watch work for example, drilling down to say 3 or 4 thou is all done in comparatively slow speed lathes or pivot drills.

          A dumore speeder with chuck is an excellent choice insofar as concentricity goes....and a pretty posh setup with the table below



          Last edited by Mcgyver; 09-27-2018, 11:51 PM.
          .

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          • #6
            One day I'll mount my TP grinder so I can drill with it.

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            • #7
              I seem to recall some guys fitting their mills with a secondary high-speed spindle for small hole drilling, any chance something like that would work here?

              If not, have you considered the rotary tool+stand route? A dremel in one of their stands would work for most applications but it sounds like youve tried that and it didnt work too well because of the dremels runout. A higher grade of rotary tool could be the ticket, I hear that Proxxon makes pretty good gear in that regard, and their literature advertises .001" or less runout. The tool and the stand runs about $200, not cheap but less than what you were looking at, plus you get a pretty sweet rotary tool out of it. Seems like that would sweeten the deal for a tool youd rarely use.

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              • #8
                The milling spindles from China are dirt cheap and can be really quite good. They are extremely commoditized. I would look at using one of those, and mounting it to an existing drill press, mill, etc.

                My experience is with the larger 2.2KW units, so I'm not sure which of the smaller units would be best. I'd ask in a forum where they are very popular.

                The cylindrical form factor makes it easy to mount. It also means you can easily remove it for other uses, like grinding on the lathe. Of course these are not for drilling, but high rpm, low-force drilling should not be a problem. People use them for CNC drilling PCB's.

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                • #9
                  That's an interesting idea. Would something like this be able to accomodate a sensitive feed chuck?
                  https://www.ebay.com/itm/DIY-Engravi...item3d6796a450

                  I'm guessing that I'd have to have an adapter made that, on one end, press fits onto the spindle and on the other, press fits onto the chuck shaft. Right?

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                  • #10
                    Originally posted by music321 View Post
                    Would something like this be able to accomodate a sensitive feed chuck?https://www.ebay.com/itm/DIY-Engravi...item3d6796a450

                    I'm guessing that I'd have to have an adapter made that, on one end, press fits onto the spindle and on the other, press fits onto the chuck shaft. Right?
                    Yes, something like that. Some spindles use a larger collet series. The collets are inexpensive. Ideally you would put your drills directly into a collet, using drills with a common shank diameter. If you change drills frequently, that would be less convenient than a chuck.

                    You could hold the chuck with a collet, using a straight shank. A shorter setup is better for runout, and some spindles may have shorter snouts. Obviously a key part of this is minimal runout. A dril in a collet will give the lowest runout. It will also have higher safe rpm capability.

                    Fwiw, the max rpm on that spindle is a bit low at 12K. My larger spindle is up to 24K. There are probably faster small spindles. A lot of folks use these for drilling circuit boards. Searching for on that should give you a lot of info on possible solutions.

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                    • #11
                      Ok, thanks.

                      Since I'm now looking at a base price of about $300 for a milling motor and a sensitive bit combined, going with a plain old high speed drill press is looking more attractive. What do you think an appropriate price for the Dumore drill press would be? By the way, it's "Dumore", not a "Dunmore". I wonder if this is just some sort of knock off. Considering it doesn't have a bit, how much do you think it would be worth? I'm sort of leary of the item at all, since it's listed as "hardly used", though it looks pretty well used.

                      As for RPM, I've heard two different things. On the one hand, I've heard that I can use a standard drill press (mine has a 3270 RPM max), and that drilling will just take longer. Others have said that high RPM is absolutely needed for smaller bits/harder materials. The reasons given are clearing performance of the bit as well as sensitivity of feel. What sorts of speeds should I be looking at for sub-millimeter drilling into glass, minerals, ceramics, etc.?

                      This 3" $10 motor is another option, but perhaps not a good one:
                      https://www.ebay.com/itm/RS-550-Moto...gAAOSwWHBaJ1vk

                      Though extreme precision is not needed, and I won't be using it that much, the above motor might just be junk due to runout and lack of torque.
                      Last edited by music321; 09-28-2018, 06:11 PM.

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                      • #12
                        The dragon has reared its ugly head- you could have only a 10 watt motor, but if you have play and flex, you will break bits. I think that's the first thing to address- getting or making a precise and rigid mechanism. I like the idea of using the ready-made spindles, or you could adapt a die grinder (a good one, not a pos). I think you can still buy collets that will fit the 1/4 inch bore and take all sizes of drill bit. Die grinders are easily powerful enough, and some can be easily adapted into a sleeve for holding in accurate alignment. Then there are the moto tools, like a dremel but larger and more robust. Some of these can take only a 1/8 inch shank, others can take 1/4 inch. You could also adapt a trim router, and many of those have speed controls on them.

                        There likely won't be a problem finding a suitable motorized spindle- personally I have leaned towards the router, as I can find those with speed controls and permanent magnet motors. Efficiency is good and power is plentiful, spindles always have ball bearings. I've hacked two of the Ryobis now and have been quite satisfied with the 'alternate' uses I've put them to.

                        Whichever part you choose to raise and lower- the head or the table- the problem to solve is really going to be the play aspect. Flex is easy to handle- use sufficient mass in the parts. Play is another animal- virtually all the small drill presses are sloppy and not suitable for small diameter carbide bits. You could perhaps use two columns and linear ball bearing guides to give a nice tight control of either the moving head or the moving table.
                        I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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                        • #13
                          The mini router idea sounds great. Is this a situation in which I shouldn't cheap out? Here's one for $30. I wonder if it's OK or junk:
                          https://www.ebay.com/itm/YaeTek-110V...bkdKL&LH_BIN=1

                          A "good" brand would cost about $70.

                          I have a table mounted router with a 1/4" collet already. It's not a "trim" router, just a run of the mill craftsman. Do you think that I could just use this?

                          If so, this is what I'm thinking:

                          I'd make a rectangular box with a bottom, top, and two sides. It will be missing two sides. I'll mount the router to the top of the box. I'll buy an Albrecht sensitive chuck to mount in the 1/4" collet. If its diameter is too wide, it can be decreased on a lathe until its a 1/4". I can then mount a platform on the bottom of the box that I can shim until it's square on the x and z axes with respect to the bit.

                          Does this seem like the best way to do things?

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                          • #14
                            What kind of work is this thing going to be doing? Unless I missed something, it seems that you will need a downfeed of some kind for the router, or an upfeed for the table. If the router allows you to adjust up and down, it's probably pretty sloppy and probably not very smooth. If the idea is to use very small drill bits at high speed, as in pc board drilling etc, then you would likely still be breaking bits. Something has to allow up/down movement smoothly, with no play.

                            If you have good carpentry skills, your rectangular box idea could work. I think I'd fix the table in place and have the router able to slide up and down. For smooth motion without slop, you could mount some ball bearing slides to the sides of the box and make that carry the router 'tray'. I've done this a few times and it works well. You don't normally use slides this way, but if you are careful to get just a little preload it does work. Both of my projects built this way use springs to carry the weight of the moving assembly, and hold it to the upward limit position. A simple lever and cable could be used to pull the 'head' downwards for drilling. You'll have all the feel you need.

                            If you build it with the table integral to the box, you still have an option to align a sacrificial table to the top of that. Use some ordinary wood screws into the fixed table and initially put them all in at the same height. The sacrificial table can then be adjusted- firstly to not rock, and secondly to be perfectly perpendicular to the drill bit. With careful construction of the box you may not need this adjustment capability at all.

                            Here's another idea- again assuming you can build accurately with mdf or plywood- just build an H-shaped section, like an I beam- this becomes your tower. To one end you attach the base, which is the table, and to the insides of the tower you mount the slides. The tray carrying the router is on those slides, with that bit of preload mentioned before. The router will obviously be forward of the slides, and what you do there sets your depth of throat. You would only need a few inches of up/down motion, so even some 10 inch slides will give you that while remaining fairly rigid. I would do this instead of the rectangular box, since you now have open access across the table, limited of course by the depth of throat. You still need a spring to raise the tray assembly- or you could use a counterweight with a cable strung over a pulley at the top of the column. My last 'makeshift' drill press is built exactly this way, from 3/4 inch mdf, and I used a cordless drill mounted to the sliding tray. This is my smallest drill press, and it's drilled about a hundred pc boards by now. The cordless drill is not fast, but I do run it on about double the voltage it was designed for. I'm going to be putting a trim router on it at some point- then I'll have a skookum pc board drill press.
                            I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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                            • #15
                              Maybe I'm mistaken as to what a "sensitive feed chuck" actually is, since I've never owned one. It's my understanding that if a sensitive feed chuck is installed in a collet, I can pull down on the feed, and this will advance the bit forward. If I relieve tension, the chuck springs back into place, right?

                              The purpose is general stuff that requires small holes. The most challenging task it will face will be little holes in agates, etc.

                              The "H" idea is interesting. I'd like to see a pic.
                              Last edited by music321; 09-28-2018, 11:30 PM.

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