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Universal mills for a HSM

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  • Universal mills for a HSM

    A guy has a Sajo mill advertised on eBay around here and when I looked at the pictures I saw it was a Universal (that is, able to swivel the table around). Unfortunately he's one of these seller who doesn't answer emails so I don't know anymore (although it looks to be a UF48 when I compare to pictures).
    I had always thought that Universals did not come in small sizes. Does anyone know of others that have a small footprint (say less than 1m2 or 3ft x 3ft) suitable for a home workshop?

    Michael

  • #2
    Pratt & Whitney 3C ( http://www.lathes.co.uk/prattwhitneymiller/ ) and the Hardinge UM ( http://www.lathes.co.uk/cataract%20miller/index.html - scroll down to the bottom of the page). The P&W is a benchtop mill and the Hardinge takes about 3ft x 3ft of space.

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    • #3
      If? I remember correctly Evan has a small one that he thinks may be Swiss made. I was amazed at the depth of cut it would take. Probably easier to find a winning lotto ticket than another one of those tho.

      Pete

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      • #4
        I have a very nice Harrisson universal mill. It is a floor model. Probably not what you'd call a real small mill,but it's table is ABOUT 8" X 30"(this is a complete guess,as I seldom use it). It does cut like crazy,and is all geared. I think Harrisson made only 1 basic mill in different configurations of vertical,horiz. and universal. see Griffith's Engineering for nice pictures and info.

        Unfortunately,the makers stopped making mills quite a while ago,and threw out all parts. That was stupid. So,if mine breaks a part I can't make,I'm stuck.

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        • #5
          Why a universal mill?

          I'm curious as to why you'd want a universal (horizontal) mill unless you are doing some spiral/helical milling?

          A swiveling table does complicate the "can't see/hidden" stuff under the table and the apron.

          My guess is that it will be used as a normal (non-universal) mill with the table clamped at zero off-set - and which it will do very well.

          If you are spiral milling and not doing by it CNC you are going to need a universal dividing head as well as some seriously complicated gear trains. The math is not easy either. This applies whether the spiral/helical/gears are cut with a normal gear cutter or hob as well.

          If I buy a machine to replace my HF-45 square column mill (not likely - but!!) it will be this vertical/horizontal mill which has a swiveling table that I don't see me needing - but if I buy that mill, I have to put up with the swiveling table:




          https://www.machineryhouse.com.au/Pr...ockCode=M161D#

          But I'd still need a universal dividing head:
          https://www.machineryhouse.com.au/Pr...stockCode=D003

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          • #6
            Glorious - or not?

            A universal mill in all its glory!!


            http://chestofbooks.com/crafts/mecha...g-Machine.html

            and:


            from:
            http://www.lathes.co.uk/victoria/index.html
            Last edited by oldtiffie; 05-29-2010, 09:17 PM.

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            • #7
              This is the small universal I have. I only know that it was privately imported from Switzerland by a gentleman that moved to Canada from there about 25 years ago. It sat nearly unused since then until I bought it from the elderly and senile owner's son. I bought the entire lot of goods including his Swiss made instruments (5 micrometres, bore gauge, master precision level, three Interapid/Tesa dial gauges, height gauge), scraping tools, surface plate, camera gear, electronics instruments and parts as well as the mill for about 900 dollars several years back. I know the son of the owner and the price was contingent on me never parting out the tools but instead actually using them to make things. That made the old man very happy and that was his greatest hope in disposing of his shop. He couldn't talk much but he gave me a big smile and a thumbs up when I left with his equipment.

              The mill has no trace of identifying marks but it is very likely Swiss made. The largest machine tool dealer in Switzerland, Luthy and Sons, has no idea who might have made it and claims to have never seen one the same. The mill has a variety of interesting features including the ability to install lever handles (included) to operate the axes instead of using the hand wheels. The table swivels and the horizontal head can be removed and attached to a (missing, but easy to make) adaptor that turns it into a vertical mill in about 60 seconds. The head also has a three in riser that gives it nearly a foot of headroom over the table. It is powered by a much later added 3 phase varispeed motor and transmission that will run it at the turn of a crank from about 30 rpm to around 1500 rpm depending on optional belt position on the step pulleys as well.

              Free software for calculating bolt circles and similar: Click Here

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              • #8
                Burke made a very nice one

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                • #9
                  Curiosity...
                  Was a "universal" largely intended for making tapered cutting tools?

                  I have seen various definitions for a "universal" in various publications of various vintage. I got the impression, though, the most often encountered use of the term was that a mill could do spiral work. Thus, there was an accessory gearbox designed to mesh with the table's leadscrew. Many of these also included a swiveling table.

                  Then I bought a manufacturer-labelled "universal" with no such spiral accessory ever made... though my table will swivel, but only to roughly five degrees. So basically enough to cut a Morse taper or other long spindle taper as well as tapered cutting tools. I might also mention that my "universal" is a horizontal by nature but with a well engineered vertical head I would hardly call an accessory. Which...

                  Leads me to the third usage I've seen for "universal": A mill with both horizontal and vertical spindle ability.

                  So does anyone know what it designated when the term was in standard use? Forgive me if I am wrong, but it seems to be an antiquated term today with little meaning and no true purpose associated with it.

                  And to link this back to the OP's question, I have a Schaublin 12 in my residential basement. It fits my home workshop needs beautifully.
                  Last edited by Arthur.Marks; 05-29-2010, 10:39 PM.

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                  • #10
                    I have a Burke #4 in my basement. It has a universal table and doesn't take up much room. Most of the parts I make are small and this little mill does an excellent job on stuff like that.

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                    • #11
                      Answers

                      Arthur.

                      I will answer your query in RED interlaced within your post.

                      Originally posted by Arthur.Marks
                      Curiosity...
                      Was a "universal" largely intended for making tapered cutting tools?

                      No. It would be easier to "cut tapers" with a tilting dividing head on any vertical or horizontal mill. The cutter would be at the top and would cut a series of triangular flats.

                      I have seen various definitions for a "universal" in various publications of various vintage. I got the impression, though, the most often encountered use of the term was that a mill could do spiral work. Thus, there was an accessory gearbox designed to mesh with the table's leadscrew. Many of these also included a swiveling table.

                      True. Just as I described in a previous post here.

                      Then I bought a manufacturer-labelled "universal" with no such spiral accessory ever made... though my table will swivel, but only to roughly five degrees. So basically enough to cut a Morse taper or other long spindle taper as well as tapered cutting tools.

                      Then you are limited to spirals with a helix angle of +/- 5 degrees.

                      I might also mention that my "universal" is a horizontal by nature but with a well engineered vertical head I would hardly call an accessory.

                      Which pretty well describes "Turret" mill or a horizontal mill with a vertical milling head attachment

                      Which...

                      Leads me to the third usage I've seen for "universal": A mill with both horizontal and vertical spindle ability.

                      See my previous answer - and which can include a BP mill with a horizontal spindle attachment.

                      So does anyone know what it designated when the term was in standard use? Forgive me if I am wrong, but it seems to be an antiquated term today with little meaning and no true purpose associated with it.

                      "Universal" as described is pretty well in universal use (sorry).

                      And to link this back to the OP's question, I have a Schaublin 12 in my residential basement. It fits my home workshop needs beautifully.

                      If any (Swiss-made) Schaublin mill, lathe or tools is/are in good condition you are very fortunate. I used them ina Tool Rooma long time ago. Thaey are a joy to use and are what others aspire to be.
                      http://www.google.com.au/#hl=en&q=sc...39eb0d6d01d192


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                      • #12
                        I take it from the information given, then, oldtiffie, that a universal mill is basically the domain of worm gear cutting. Other necessary uses for the feature(s) of a true universal mill would be rare. Agreed?

                        Still... it seems to me like it would be the foremost (antiquated) method of producing twist drills, spiral mills, and the like.
                        Last edited by Arthur.Marks; 05-30-2010, 01:31 AM.

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                        • #13
                          I apologize for the thread-jack here.

                          "The universal milling machine was invented in 1862 by Joseph R. Brown... It is so constructed that the table may be swiveled to a considerable angle in a horizontal plane to permit the milling of spiral (twisted) grooves...
                          "The plain milling machine is a simplified version of the standard knee-type milling machine... It is very similar in appearance and construction to the universal milling machine, differing chiefly in that it lacks the swivel-table construction."ppg. 133-134
                          Machine Tool Operation, Part II, Burghardt and Axelrod (c)1954

                          Regardless, I agree with the earlier question directed to form_change, "Why a universal mill?"
                          Last edited by Arthur.Marks; 05-30-2010, 01:31 AM.

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                          • #14
                            Zero spiral and table off-set

                            Originally posted by Arthur.Marks
                            I take it from the information given, then, oldtiffie, that a universal mill is basically the domain of worm gear cutting. Other necessary uses for the feature(s) of a true universal mill would be rare. Correct?

                            Still... it seems to me like it would be the foremost (antiquated) method of producing twist drills, spiral mills, and the like.
                            Arthur.

                            The off-set of the table will determine the limit of the helix angle of the grooves you are cutting.

                            5 degrees is about the limit for accuracy before serious consideration has to be given for "twisting" of a tooth form. In other words, if you were cutting a spiral gear the limit on the spiral gear would be five degrees so that you could use standard gear-cutters (store-bought).

                            Worm gear cutting is an entirely different matter as a universal is best for the job but it can be done on a non-universal mill by rotating the base of the dividing head the amount that the universal table would have been tilted/off-set.

                            When cutting a true form worm-wheel, a hobbing cutter mounted on the horizontal arbor is required - but - and here is the difference to the gearing set-ups mentioned previously (where the dividing head rotation was geared to and synchronised with the mill "X" lead-screw) in the case of milling/hobbing a worm-wheel the "X" and "Y" slides are locked/clamped and the universal dividing head spindle is geared to and synchronised with the mill spindle (and the arbor and the hobbing cutter which must be keyed to the arbor).

                            In most cases in a HSM shop a worm-wheel is best cut on a lathe with an "interrupted thread" cutter (like a gashed lead-screw or a tap) driven by the lahte head-stock spindle and the worm blank mounted on the lathe cross-slide and left to "free-wheel" and be "pulled around" as it is cut by the helical cutter. The action is not dissimilar to what you'd see on a domestic mincer.

                            Universal mills really do need a good universal dividing head as well as a very good gear train and mountings to get the "best" out of the "universal" capacity.

                            Check it out in "Machinery's Handbook".

                            Taps and "lead-screw" cutters and the like - and hobbing cutters - can be made with straight (zero helix angles) provided the helix angle of the cutter is not more than 5>10 degrees off-set from normal (90 degrees).

                            I suspect that as many "universal" mills as there are that are sold are to people who are impressed with "universal" over "plain" - and pay a premium for it. The down-side is that those of us that only want a plain mill have to take and pay for a "universal" feature that we neither want not need.

                            So, in short, for most cases the "universal" feature is neither here nor there and should/can be set to zero and forgotten about.

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                            • #15
                              The original question was not should I get a Universal but what small-ish Universals are there out there that might be of a suitable size for a HSM. The only Universal mills I have seen have been in an industrial context and were usually large machines used in a tool-room for special work. I wanted to know whether smaller machines were all that common or whether this machine was comparatively rare.

                              My interest in this particular machine was that it looked to be a similar size to the mill I have but a step up (powered feeds, heavier construction, (the swivel table), greater HP, slightly larger table). Even without the swivel table I would consider it, but as I do cut the occasional gear the swivel seems a bonus.

                              For those who would denigrate a machine with features they rarely use, I would firstly say that it's my preference as to what features I regard as important to have on my machines - my lathe has a taper turning device that I may use once a year, but I'm not getting rid of it just because I don't use it often.

                              By all means buy a new Chinese machine from the local machinery supermarket if you think that is the best option. I think I get much better value for money by fixing up and then using second hand machines but sometimes you don't get to choose what factory options are fitted.

                              The other point worth making is that just because it is not commonly used does not mean that it will not be used in the future. Buying a tool or machine after you need the functionality is pointless. Buying before it's needed makes much more sense. Is anyone here planning to remove the seat belts, air bags, spare wheel and jack from their cars as they don't use them?

                              Michael

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