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Re: [atlas_craftsman] Steel v. Al. Risers

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  • jtiers
    Not at all what I have seen. But machines vary in the amount of wear they have, and in the type of wear. Amount and type of wear influences chatter. A
    Message 1 of 14 , Jul 26, 2013
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      Not at all what I have seen. 
       
      But machines vary in the amount of wear they have, and in the type of wear.  Amount and type of wear influences chatter.  A machine with significant "rocking horse" wear on the saddle will chatter like a lunchroom full of teenage girls, for instance.
       
      Using a single phase motor is almost unfair when discussing chatter, since the torque variation is a huge driver of chatter.  Going to 3 phase makes a rather large difference, in my experience, and brings out the real differences in machines. 
       
      I find that my 3 phase Logan 10" will happily take a D.O.C. up to about 1/4" without complaint on material of 1.5" or so diameter, and causes no trouble with parting off..  Larger work is limited by the 1/3 HP motor and the flat belt far more than by chatter.   
       
      In general, you can look at the bed width, and the depth of the bed, and see what your general performance will be.  A bed width less than the spindle height is generally bad, and the machine with the most bed depth (top to bottom) generally will be stiffer.  Logan in particular has a wide bed, a 10" Logan has a bed width of  7" vs a spindle height of 5.5",  and a depth of something over 4" top to bottom.  IIRC the last Atlas I had much to do with was somewhat narrower and shallower.
       
      However, before getting some of you all up in arms, I may mention that the 7 x 4 Logan bed isn't "enough"....    And the Logan saddle, while somewhat larger than the Atlas, still isn't like a S-B 13" saddle, which probably weighs as much as the whole bed of an Atlas.  Weight (mass) and size count, and have a huge influence on chatter, surface finish, etc.
       
      NONE of the small lathes, Atlas, Southbend workshop, Logan, or smaller Sheldon and Clausing are in any way comparable to a "real" lathe.  Just a fact.  There is so much more mass and inertia with a large lathe that what causes chatter with a small lathe is not even noticed on a "real" lathe.
       
      All the issues of wear, stiffness, etc, almost surely completely "bury" the tiny influence of the material stiffness differences between steel, cast iron, or aluminum risers.  The mass difference might make a findable difference, but you could have to look rather hard to see it.
       
      JT
       
       
      ----- Original Message -----
      From: Doc
      Sent: Friday, July 26, 2013 8:57 PM
      Subject: Re: [atlas_craftsman] Steel v. Al. Risers

      FWIW  several years  ago , after  reading  a litany of  pejorative  comments  on  atlas/crftsmn lathes , i ran  some  VERY  unscientific tests  on a 1974 craftsman commercial  12 in, vs circa 1960 wards  logan  10in.....i took some  cuts  w/ a  broad face cutting  bit at  various speeds ,  on a  bar of  1018 .&.adjusting  speeds till chatter  ocurred & noting  sucjh  speeds ........because of  the differeing   speeds  available  on the two  lathes it was  inexact ...but  my  IMPRESSION of the  results  was that  they  were pretty  well EVEN  ......since  the  atlas crftsmn had an  additional extra  inch  of cantilever  moment ,one may  even conclude that  it  was  the  stiffer of  the  two ...but  again   only an impression  based  on trials  that  were  less than ideal .....in the  case of  the  earlier 3/8 thick bed lathes , i wud xpect  the result to favor  the  wards  logan ...it  shud be noted  that  the  wards logan sold  for near  double  that of the   crftsmn  .......around  1970 when i priced  my  12x36 , the  south  bend light  ten sold  for MORE than  double  the  atlas,,,
       FWIW 2 ...maybe  because of  familiarity , but  the crftsmn  is the "handiest"  of  the  6  lathes  i have  that  are in  occaisional  use ....all well tooled ,,,,,,,,,the  12in  crftsmn  will not  take a  2 in 1018 bar  down to one in  in a single  pass @circa 144 rpm like my  monarch 14 in mod A will , but in  home  shop, so  what ?
       best  wishes
      doc
    • Jon Elson
      ... About 2005 I moved up to a 15 Sheldon R15 lathe, this is a 5 Hp 3500 Lb machine with a D1-6 spindle mount and a 2.25 spindle through hole. I had to do a
      Message 2 of 14 , Jul 27, 2013
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        Doc wrote:
        >
        >
        > FWIW several years ago , after reading a litany of pejorative
        > comments on atlas/crftsmn lathes , i ran some VERY unscientific
        > tests on a 1974 craftsman commercial 12 in, vs circa 1960 wards
        > logan 10in
        About 2005 I moved up to a 15" Sheldon R15 lathe, this is a 5 Hp
        3500 Lb machine with a D1-6 spindle mount and a 2.25" spindle
        through hole. I had to do a massive regrind of the bed to correct
        a badly worn area, but that is now fixed.

        There SURE is a difference! But, if your test was to tell if
        the flat ways were what made the difference, then I think
        you got your answer. It is largely the stiffness of the bed,
        and also the stiffness of the carriage, cross-slide, compound,
        toolpost stack. On my Sheldon, the cross slide is about as
        big as the Atlas main ways, and the compound is not much smaller.
        These parts are REALLY stiff. On the Atlas, you can visibly deflect
        the stack by pushing on the toolpost.

        I still find parting-off a little bit of a challenge, maybe because
        I often do light workpieces, mostly in aluminum. But, it works
        a lot better than my previous 12" late-model Craftsman.

        Another area where you really see the difference is when
        turning such that you get a wide chip. On the Atlas, if the chip
        was wider than 1/8", you would almost always get chatter,
        which could build to a level where the whole lathe bench would
        "dance" on the floor. On the Sheldon, I made a form too to
        make a 1" ball joint socket. So, this was a 1/2" toolbit cut
        to a radius of 1/2", with a quarter-round profile. When
        cutting, the chip was .785" wide (1/4 of Pi*D where D=1")
        I made this out of 1018 steel, and it just made a crinkling
        sound as the chips crumpled inward on themselves. That
        was my acid test that showed the lathe was working perfectly.

        So, mass and stiffness really make a difference, and that is
        the weak point on the Atlas.

        (Not trying to gloat here, just pointing out your test
        compared two lightly-made lathes, and the fact they came
        out about the same would be expected.)

        Jon
      • Doc
        hi Jon well stated .. ...& because of the deficiencies in the light lathes, the goosenck type flex holder mitigates some of the deficicncy
        Message 3 of 14 , Jul 27, 2013
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          hi Jon
             well stated ..
             ...& because  of the  deficiencies in the  light   lathes,  the  goosenck type  flex  holder mitigates  some of  the deficicncy ....somewhere along  the  line  i acquired  a  home  shop made flex  holder ..gooseneck style & VERY  flexible .....using  this  on an 1895  14 in  lathe  ( circa 1750#) w/ a rise /fall tool post  ( not  the  most  ridgid ) , i can  plunge  cut a point on a  one in 1018 bar in first  speed  open  gear , w/ a full width flat  point on a  3/8  bit w/out  chatter ( watch it  flex  near a  1/16 )  ...IMPOSSIBLE  w/a  solid  holder
            so i use it  on  the  12x36  crftsmn  when needed , like  a  form  tool .......because of  this i started  working  w/ gooseneck parting  tools .........and.THAT plus a solid  block tool holder & near  all my  parting  problems  disappeared  on the  cfrtsmn  comercial....when i ground slight  FRONT  to BACK  clearance on the  blade   AND a V on the  cutting face ,  the  rest  of the  problems  disappeared.....the  V collapses  the  chip into smaller chips  giving  MUCH  better  clearance ....
             ..heresy , BUT ,the last  few  cutoffs  on 1/2 to  one in  mild  steel  bars  were  done  w/out  cutting  fluid ,,,dry !...still experimenting ....
             .oh  yeah , one DOES NOT  use  power  xfeed  cutting off on an  atlas  crftsmn ... X feed is just too fast  ..
             nice thing  abt  logan  10 in  is  the  x feed is  1/4  of  the  lingitudinal feed ...atlas  crftsmen  is  one to one .
          ...
            ENVIOUS  of the rescraped  sheldon 15 ...( but  not  of what  you went  through bringing  it  back
          )
          a .question : is it  as  "handy" as the  crftsmn commercial you previosly  had ? or  more  so ?
           
           i have a circa 1917  2000# monarch  A ,well tooled  ,as well as a 15 in 1890 Prentice  bros  lathe  that  is  lighter  than  the 14in 1890 Reed  by  several hundred  pounds ..these are  luckily still in  good  useable  condition ( max 9 thou bed wear , but  the  long /wide carriage ( abt  22 in or  so  makes it  fairly even for  most of  the bed length ),  & i go to them for the larger  work  when  needed .....
           
          .have  never  used a  3500-4000 #  lathe , or  seen one in  use
           probably  a  good  thing  or  i wud  be  disatisfied w/ my  antiques
              
           best  wishes
          doc
          -----Original Message-----
          From: Jon Elson <elson@...>
          To: atlas_craftsman <atlas_craftsman@yahoogroups.com>
          Sent: Sat, Jul 27, 2013 10:58 am
          Subject: Re: [atlas_craftsman] Steel v. Al. Risers

           
          Doc wrote:
          >
          >
          > FWIW several years ago , after reading a litany of pejorative
          > comments on atlas/crftsmn lathes , i ran some VERY unscientific
          > tests on a 1974 craftsman commercial 12 in, vs circa 1960 wards
          > logan 10in
          About 2005 I moved up to a 15" Sheldon R15 lathe, this is a 5 Hp
          3500 Lb machine with a D1-6 spindle mount and a 2.25" spindle
          through hole. I had to do a massive regrind of the bed to correct
          a badly worn area, but that is now fixed.

          There SURE is a difference! But, if your test was to tell if
          the flat ways were what made the difference, then I think
          you got your answer. It is largely the stiffness of the bed,
          and also the stiffness of the carriage, cross-slide, compound,
          toolpost stack. On my Sheldon, the cross slide is about as
          big as the Atlas main ways, and the compound is not much smaller.
          These parts are REALLY stiff. On the Atlas, you can visibly deflect
          the stack by pushing on the toolpost.

          I still find parting-off a little bit of a challenge, maybe because
          I often do light workpieces, mostly in aluminum. But, it works
          a lot better than my previous 12" late-model Craftsman.

          Another area where you really see the difference is when
          turning such that you get a wide chip. On the Atlas, if the chip
          was wider than 1/8", you would almost always get chatter,
          which could build to a level where the whole lathe bench would
          "dance" on the floor. On the Sheldon, I made a form too to
          make a 1" ball joint socket. So, this was a 1/2" toolbit cut
          to a radius of 1/2", with a quarter-round profile. When
          cutting, the chip was .785" wide (1/4 of Pi*D where D=1")
          I made this out of 1018 steel, and it just made a crinkling
          sound as the chips crumpled inward on themselves. That
          was my acid test that showed the lathe was working perfectly.

          So, mass and stiffness really make a difference, and that is
          the weak point on the Atlas.

          (Not trying to gloat here, just pointing out your test
          compared two lightly-made lathes, and the fact they came
          out about the same would be expected.)

          Jon
        • Jon Elson
          ... Well, I looked long and hard before jumping for this one. The standard version does 45-1250 RPM, there is a high-speed version that goes to 2500 RPM using
          Message 4 of 14 , Jul 27, 2013
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            Doc wrote:
            >
            > )
            > a .question : is it as "handy" as the crftsmn commercial you
            > previosly had ? or more so ?
            >
            > i have a circa 1917 2000# monarch A ,well tooled ,as well as a 15
            > in 1890 Prentice bros lathe that is lighter than the 14in 1890
            > Reed by several hundred pounds ..these are luckily still in good
            > useable condition ( max 9 thou bed wear , but the long /wide
            > carriage ( abt 22 in or so makes it fairly even for most of the
            > bed length ), & i go to them for the larger work when needed .....
            >
            Well, I looked long and hard before jumping for this one. The standard
            version does 45-1250 RPM, there is a high-speed version that goes to
            2500 RPM using a dual-speed motor. (I don't have the dual speed
            version, but find 1250 is plenty of RPM.) It is a very sophisticated
            lathe, except in back gear there are no gears in the headstock to
            remove vibrations. (The gears are in the motor.) The input pulley
            runs on separate bearings on the headstock casting, not on the
            spindle, like the Atlas. Again, removes vibrations. The power feed
            and crossfeed are driven by friction clutches so it hopefully survives
            crashes without broken gears. The feeds and threading leadscrew
            are interlocked so you can't engage both, and there are trip buttons
            that stop the feed automatically. The feed shaft is separate from the
            threading screw, and has universal joints on the end so it doesn't
            provide a rocking motion to the carriage. I could go on, but
            it is just VERY well designed.

            And, to answer your question, no, it really doesn't get in the
            way. The Atlas lathe did get in the way, mostly the small spindle
            through-hole. But, I can imagine some of the very old, large
            lathes might not be so flexible. I really only have room for
            one lathe.

            Jon
          • Doc
            tnx jon ,,,,another great sheldon product yes , the antique large lathes are very basic , leaving things to be desired ......the 1895 Reed 14 in
            Message 5 of 14 , Jul 27, 2013
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              tnx  jon ,,,,another  great  sheldon  product
               
              yes , the  antique large  lathes  are  very  basic , leaving  things  to be  desired ......the  1895  Reed 14 in  will not  pass more than a 5/8  rod thru  the  spindle   they  drilled 3/4 from both  ends & the  drill wandered off a  tad ...the  monarch A  will pass 11/4 in, just  under  what  is  needed for a 5 c  draw  tube ..
                 .i do not  know  when  interlocks came into  use  , but the circa 1917 monarch  has the feed/ thread  interlock  ,,the  19 th  century machines  do  not ........one   plus tho is that they  were  built to LAST , &  near  all that can go wrong can  be repaired  w/ a  torch & a lathe ...i have a shaper  built  somewhere between 1857 &  1862 ,that is in regular  home  shop use......
                  re  space.....basement  is full &  a 2-1/2 car  attached  garage  that i built has  never  had  space  for  a  road vehicle  in 30  yrs......but  again , a  plus  is  that  i am the  safest  in my shop ..no way  can i fall &  break a  hip ....i will literally bang into a  machine  first  !!!!
                  best  wishes
              doc
              -----Original Message-----
              From: Jon Elson <elson@...>
              To: atlas_craftsman <atlas_craftsman@yahoogroups.com>
              Sent: Sat, Jul 27, 2013 5:51 pm
              Subject: Re: [atlas_craftsman] Steel v. Al. Risers

               
              Doc wrote:
              >
              > )
              > a .question : is it as "handy" as the crftsmn commercial you
              > previosly had ? or more so ?
              >
              > i have a circa 1917 2000# monarch A ,well tooled ,as well as a 15
              > in 1890 Prentice bros lathe that is lighter than the 14in 1890
              > Reed by several hundred pounds ..these are luckily still in good
              > useable condition ( max 9 thou bed wear , but the long /wide
              > carriage ( abt 22 in or so makes it fairly even for most of the
              > bed length ), & i go to them for the larger work when needed .....
              >
              Well, I looked long and hard before jumping for this one. The standard
              version does 45-1250 RPM, there is a high-speed version that goes to
              2500 RPM using a dual-speed motor. (I don't have the dual speed
              version, but find 1250 is plenty of RPM.) It is a very sophisticated
              lathe, except in back gear there are no gears in the headstock to
              remove vibrations. (The gears are in the motor.) The input pulley
              runs on separate bearings on the headstock casting, not on the
              spindle, like the Atlas. Again, removes vibrations. The power feed
              and crossfeed are driven by friction clutches so it hopefully survives
              crashes without broken gears. The feeds and threading leadscrew
              are interlocked so you can't engage both, and there are trip buttons
              that stop the feed automatically. The feed shaft is separate from the
              threading screw, and has universal joints on the end so it doesn't
              provide a rocking motion to the carriage. I could go on, but
              it is just VERY well designed.

              And, to answer your question, no, it really doesn't get in the
              way. The Atlas lathe did get in the way, mostly the small spindle
              through-hole. But, I can imagine some of the very old, large
              lathes might not be so flexible. I really only have room for
              one lathe.

              Jon
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