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Re: [southbend10k] Heavy 10 headstock alignment problem

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  • Ed Beers
    ... I have a war board (early 40s) heavy 10 with the dowel pin and clamped in place as you describe. I also have a much newer one with the same arrangement.
    Message 1 of 16 , Sep 19, 2007
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      ALAN WHEATLEY wrote:
      >
      > I don't know when SB were using a dowel pin for this or which models
      > have the system, but the headstock of my own 1939/1940 Heavy 10 is
      > clamped to the bed from below by hex screws passing through a loose
      > bridge piece. Did later lathes or non-gearbox models use screws
      > to directly fasten and locate their headstocks?
      >







      I have a war board (early 40s) heavy 10 with the dowel pin and clamped
      in place as
      you describe. I also have a much newer one with the same arrangement.

      Ed
    • Chet R Biggerstaff
      ... along the bed so that gears on the banjo arm line up with tumbler gears on the headstock and the input gear at the quick change gearbox. ... models have
      Message 2 of 16 , Sep 20, 2007
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        --- In southbend10k@yahoogroups.com, ALAN WHEATLEY
        <alan.wheatley10@...> wrote:
        >
        > Chris
        >
        > Some SB machines have a dowel pin locating the headstock lengthways
        along the bed so that gears on the banjo arm line up with tumbler
        gears on the headstock and the input gear at the quick change gearbox.
        >
        > I don't know when SB were using a dowel pin for this or which
        models have the system, but the headstock of my own 1939/1940 Heavy
        10 is clamped to the bed from below by hex screws passing through a
        loose bridge piece. Did later lathes or non-gearbox models use screws
        to directly fasten and locate their headstocks?
        >
        > Alan
        >
        > Chris Strazzeri wrote:
        > Firstly, I don't know why your HS is pinned. It should be secured
        to the bed with cap screws. The fact that it is pinned, has very
        little to do with your taper problem. Have you leveled the lathe with
        a precision machinist level & have you checked for bed wear near the
        HS? You must eliminate any bed twist before doing anything.
        >
        > Chris
        >
        >
        > Chet R Biggerstaff <Chet@...> wrote:
        > I have just bought a heavy 10 lathe and started testing it to see
        what
        > it needs. I have found that in the 3 jaw chuck with a peice of
        12l14
        > round stock sticking out 4.5" that it is 5 thou smaller at the far
        end
        > (no tailstock support). The headstock is pined to the bed so there
        does
        > not seem to be any adjustment to take this out. Any ideas?
        >
      • Chet R Biggerstaff
        turned a taper on the bar i cut it. ... turned a ... other ... on ... diameter - ... the ... 12l14 ... far ... there
        Message 3 of 16 , Sep 20, 2007
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          turned a taper on the bar i cut it.

          --- In southbend10k@yahoogroups.com, "one2watch999" <mark@...> wrote:
          >
          > Just to claer up my understanding - do you mean that you have
          turned a
          > bar mounted in the 3 jaw and the one end is smaller than the the
          other
          > (turned a taper) or do you mean that measuring with a DTI mounted
          on
          > the cross slide a plain round bar deviates along it's length (when
          > mounted in the 3 jaw)?
          >
          > The reason I ask is that differences in turned diameters indicate
          > misalignement in the bed/lathe setup but deviations in an un-turned
          > bar mounted in the chuck would probably be expected from the normal
          > error found in a 3 Jaw (unless it has been trued at the test
          diameter -
          > and even then it may not be gripping the stock concentric).
          >
          > When I set my Boxford, I used a machine level (I know this is
          > contentious but that is how I like to do it!) and a test bar with a
          > suitable morse taper driven into the head. Works for me, and was
          the
          > way the machine fitters always set lathes up the shops I worked
          > in/with.
          >
          > Regards
          >
          > Mark
          >
          > --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff" <Chet@>
          > wrote:
          > >
          > > I have just bought a heavy 10 lathe and started testing it to see
          > what
          > > it needs. I have found that in the 3 jaw chuck with a peice of
          12l14
          > > round stock sticking out 4.5" that it is 5 thou smaller at the
          far
          > end
          > > (no tailstock support). The headstock is pined to the bed so
          there
          > does
          > > not seem to be any adjustment to take this out. Any ideas?
          > >
          >
        • kgregg@indy.rr.com
          My heavy 10 sounds just like yours (i.e. it has a pin to locate its position on the bed). I first leveled the bed with a machinist s level (very important).
          Message 4 of 16 , Sep 20, 2007
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            My heavy 10 sounds just like yours (i.e. it has a pin to locate its
            position on the bed). I first leveled the bed with a machinist's
            level (very important). A previous owner hacked the bottom of the
            headstock for some reason so once I leveled the bed, I used a
            combination of cutting test bars and running dial indicators to shim
            under the headstock. Now that I have it perfect, I will hopefully
            never remove the headstock from the bed.

            -Kevin

            ----- Original Message -----
            From: Chet R Biggerstaff <Chet@...>
            Date: Thursday, September 20, 2007 1:15 pm
            Subject: [southbend10k] Re: Heavy 10 headstock alignment problem
            To: southbend10k@yahoogroups.com

            > turned a taper on the bar i cut it.
            >
            > --- In southbend10k@yahoogroups.com, "one2watch999" <mark@...> wrote:
            > >
            > > Just to claer up my understanding - do you mean that you have
            > turned a
            > > bar mounted in the 3 jaw and the one end is smaller than the the
            > other
            > > (turned a taper) or do you mean that measuring with a DTI
            > mounted
            > on
            > > the cross slide a plain round bar deviates along it's length
            > (when
            > > mounted in the 3 jaw)?
            > >
            > > The reason I ask is that differences in turned diameters
            > indicate
            > > misalignement in the bed/lathe setup but deviations in an un-
            > turned
            > > bar mounted in the chuck would probably be expected from the
            > normal
            > > error found in a 3 Jaw (unless it has been trued at the test
            > diameter -
            > > and even then it may not be gripping the stock concentric).
            > >
            > > When I set my Boxford, I used a machine level (I know this is
            > > contentious but that is how I like to do it!) and a test bar
            > with a
            > > suitable morse taper driven into the head. Works for me, and was
            > the
            > > way the machine fitters always set lathes up the shops I worked
            > > in/with.
            > >
            > > Regards
            > >
            > > Mark
            > >
            > > --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff"
            > <Chet@>
            > > wrote:
            > > >
            > > > I have just bought a heavy 10 lathe and started testing it to
            > see
            > > what
            > > > it needs. I have found that in the 3 jaw chuck with a peice of
            > 12l14
            > > > round stock sticking out 4.5" that it is 5 thou smaller at the
            > far
            > > end
            > > > (no tailstock support). The headstock is pined to the bed so
            > there
            > > does
            > > > not seem to be any adjustment to take this out. Any ideas?
            > > >
            > >
            >
            >
            >
          • one2watch999
            Yes, I noticed the post on the the other site and have since decided that that was the case - you have had the answer you need in terms of the posting about
            Message 5 of 16 , Sep 20, 2007
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              Yes, I noticed the post on the the other site and have since decided
              that that was the case - you have had the answer you need in terms of
              the posting about Rollies Dads method - this will give you the best
              solution with the minimum of special kit. You can also check bed wear
              easily with a clock on the saddle - dial it in on the flat tailstock
              way and traverse the saddle - there should be very little wear on
              this way as the tailstock is not "normally" used anything like as
              much as the saddle. If you have little variation over the bed then
              the problem is almost certainly twist and should be easily un-twisted.

              As I said, I set my Boxford underdrive using a machine level to fix
              the bed - which took quite some time as my lathe has no adjustment on
              the riser blocks and needs to seal to the cabinet (which prevents
              using standard jack feet). I used shims and a load of spare time!
              When the bed was true to within a thou or so all over I mounted the
              head to find that this was also out! Rather than scrape the mountings
              I shimmed the head as well, Sounds drastic but this is not a brand
              new machine and you have to take this in consideration. I have ended
              up with a machine that has tailstock that is pretty close to the
              headstock and generally turns quite true. As I said, it is an old
              machine so I don't expect to turn optical standard work! it will turn
              to a better standard than I can with any consistancy so when I am as
              good as the machine I might start to look deeper!

              Mark


              --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff" <Chet@...>
              wrote:
              >
              > turned a taper on the bar i cut it.
              >
              > --- In southbend10k@yahoogroups.com, "one2watch999" <mark@> wrote:
              > >
              > > Just to claer up my understanding - do you mean that you have
              > turned a
              > > bar mounted in the 3 jaw and the one end is smaller than the the
              > other
              > > (turned a taper) or do you mean that measuring with a DTI mounted
              > on
              > > the cross slide a plain round bar deviates along it's length
              (when
              > > mounted in the 3 jaw)?
              > >
              > > The reason I ask is that differences in turned diameters indicate
              > > misalignement in the bed/lathe setup but deviations in an un-
              turned
              > > bar mounted in the chuck would probably be expected from the
              normal
              > > error found in a 3 Jaw (unless it has been trued at the test
              > diameter -
              > > and even then it may not be gripping the stock concentric).
              > >
              > > When I set my Boxford, I used a machine level (I know this is
              > > contentious but that is how I like to do it!) and a test bar with
              a
              > > suitable morse taper driven into the head. Works for me, and was
              > the
              > > way the machine fitters always set lathes up the shops I worked
              > > in/with.
              > >
              > > Regards
              > >
              > > Mark
              > >
              > > --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff" <Chet@>
              > > wrote:
              > > >
              > > > I have just bought a heavy 10 lathe and started testing it to
              see
              > > what
              > > > it needs. I have found that in the 3 jaw chuck with a peice of
              > 12l14
              > > > round stock sticking out 4.5" that it is 5 thou smaller at the
              > far
              > > end
              > > > (no tailstock support). The headstock is pined to the bed so
              > there
              > > does
              > > > not seem to be any adjustment to take this out. Any ideas?
              > > >
              > >
              >
            • Chet R Biggerstaff
              i just finished leveling the lathe and im within 1 thou in 5 inches with the 3jaw. Is this good or should i be able to get it all out? ... shim ... the ...
              Message 6 of 16 , Sep 20, 2007
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                i just finished leveling the lathe and im within 1 thou in 5 inches
                with the 3jaw. Is this good or should i be able to get it all out?


                --- In southbend10k@yahoogroups.com, kgregg@... wrote:
                >
                > My heavy 10 sounds just like yours (i.e. it has a pin to locate its
                > position on the bed). I first leveled the bed with a machinist's
                > level (very important). A previous owner hacked the bottom of the
                > headstock for some reason so once I leveled the bed, I used a
                > combination of cutting test bars and running dial indicators to
                shim
                > under the headstock. Now that I have it perfect, I will hopefully
                > never remove the headstock from the bed.
                >
                > -Kevin
                >
                > ----- Original Message -----
                > From: Chet R Biggerstaff <Chet@...>
                > Date: Thursday, September 20, 2007 1:15 pm
                > Subject: [southbend10k] Re: Heavy 10 headstock alignment problem
                > To: southbend10k@yahoogroups.com
                >
                > > turned a taper on the bar i cut it.
                > >
                > > --- In southbend10k@yahoogroups.com, "one2watch999" <mark@> wrote:
                > > >
                > > > Just to claer up my understanding - do you mean that you have
                > > turned a
                > > > bar mounted in the 3 jaw and the one end is smaller than the
                the
                > > other
                > > > (turned a taper) or do you mean that measuring with a DTI
                > > mounted
                > > on
                > > > the cross slide a plain round bar deviates along it's length
                > > (when
                > > > mounted in the 3 jaw)?
                > > >
                > > > The reason I ask is that differences in turned diameters
                > > indicate
                > > > misalignement in the bed/lathe setup but deviations in an un-
                > > turned
                > > > bar mounted in the chuck would probably be expected from the
                > > normal
                > > > error found in a 3 Jaw (unless it has been trued at the test
                > > diameter -
                > > > and even then it may not be gripping the stock concentric).
                > > >
                > > > When I set my Boxford, I used a machine level (I know this is
                > > > contentious but that is how I like to do it!) and a test bar
                > > with a
                > > > suitable morse taper driven into the head. Works for me, and
                was
                > > the
                > > > way the machine fitters always set lathes up the shops I worked
                > > > in/with.
                > > >
                > > > Regards
                > > >
                > > > Mark
                > > >
                > > > --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff"
                > > <Chet@>
                > > > wrote:
                > > > >
                > > > > I have just bought a heavy 10 lathe and started testing it to
                > > see
                > > > what
                > > > > it needs. I have found that in the 3 jaw chuck with a peice
                of
                > > 12l14
                > > > > round stock sticking out 4.5" that it is 5 thou smaller at
                the
                > > far
                > > > end
                > > > > (no tailstock support). The headstock is pined to the bed so
                > > there
                > > > does
                > > > > not seem to be any adjustment to take this out. Any ideas?
                > > > >
                > > >
                > >
                > >
                > >
                >
              • Chet R Biggerstaff
                make that 5 ten thousandths in 5 inches ... inches ... its ... the ... hopefully ... worked ... to ... so
                Message 7 of 16 , Sep 20, 2007
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                  make that 5 ten thousandths in 5 inches

                  --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff" <Chet@...>
                  wrote:
                  >
                  > i just finished leveling the lathe and im within 1 thou in 5
                  inches
                  > with the 3jaw. Is this good or should i be able to get it all out?
                  >
                  >
                  > --- In southbend10k@yahoogroups.com, kgregg@ wrote:
                  > >
                  > > My heavy 10 sounds just like yours (i.e. it has a pin to locate
                  its
                  > > position on the bed). I first leveled the bed with a machinist's
                  > > level (very important). A previous owner hacked the bottom of
                  the
                  > > headstock for some reason so once I leveled the bed, I used a
                  > > combination of cutting test bars and running dial indicators to
                  > shim
                  > > under the headstock. Now that I have it perfect, I will
                  hopefully
                  > > never remove the headstock from the bed.
                  > >
                  > > -Kevin
                  > >
                  > > ----- Original Message -----
                  > > From: Chet R Biggerstaff <Chet@>
                  > > Date: Thursday, September 20, 2007 1:15 pm
                  > > Subject: [southbend10k] Re: Heavy 10 headstock alignment problem
                  > > To: southbend10k@yahoogroups.com
                  > >
                  > > > turned a taper on the bar i cut it.
                  > > >
                  > > > --- In southbend10k@yahoogroups.com, "one2watch999" <mark@>
                  wrote:
                  > > > >
                  > > > > Just to claer up my understanding - do you mean that you have
                  > > > turned a
                  > > > > bar mounted in the 3 jaw and the one end is smaller than the
                  > the
                  > > > other
                  > > > > (turned a taper) or do you mean that measuring with a DTI
                  > > > mounted
                  > > > on
                  > > > > the cross slide a plain round bar deviates along it's length
                  > > > (when
                  > > > > mounted in the 3 jaw)?
                  > > > >
                  > > > > The reason I ask is that differences in turned diameters
                  > > > indicate
                  > > > > misalignement in the bed/lathe setup but deviations in an un-
                  > > > turned
                  > > > > bar mounted in the chuck would probably be expected from the
                  > > > normal
                  > > > > error found in a 3 Jaw (unless it has been trued at the test
                  > > > diameter -
                  > > > > and even then it may not be gripping the stock concentric).
                  > > > >
                  > > > > When I set my Boxford, I used a machine level (I know this is
                  > > > > contentious but that is how I like to do it!) and a test bar
                  > > > with a
                  > > > > suitable morse taper driven into the head. Works for me, and
                  > was
                  > > > the
                  > > > > way the machine fitters always set lathes up the shops I
                  worked
                  > > > > in/with.
                  > > > >
                  > > > > Regards
                  > > > >
                  > > > > Mark
                  > > > >
                  > > > > --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff"
                  > > > <Chet@>
                  > > > > wrote:
                  > > > > >
                  > > > > > I have just bought a heavy 10 lathe and started testing it
                  to
                  > > > see
                  > > > > what
                  > > > > > it needs. I have found that in the 3 jaw chuck with a peice
                  > of
                  > > > 12l14
                  > > > > > round stock sticking out 4.5" that it is 5 thou smaller at
                  > the
                  > > > far
                  > > > > end
                  > > > > > (no tailstock support). The headstock is pined to the bed
                  so
                  > > > there
                  > > > > does
                  > > > > > not seem to be any adjustment to take this out. Any ideas?
                  > > > > >
                  > > > >
                  > > >
                  > > >
                  > > >
                  > >
                  >
                • Kevin Gregg
                  You should be able to get under a thou in five inches for sure. ... From: Chet R Biggerstaff To: southbend10k@yahoogroups.com Sent: Thursday, September 20,
                  Message 8 of 16 , Sep 21, 2007
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                    You should be able to get under a thou in five inches for sure.
                     
                    ----- Original Message -----
                    Sent: Thursday, September 20, 2007 9:30 PM
                    Subject: [southbend10k] Re: Heavy 10 headstock alignment problem

                    make that 5 ten thousandths in 5 inches

                    --- In southbend10k@ yahoogroups. com, "Chet R Biggerstaff" <Chet@...>
                    wrote:
                    >
                    > i just finished leveling the lathe and im within 1 thou in 5
                    inches
                    > with the 3jaw. Is this good or should i be able to get it all out?
                    >
                    >
                    > --- In southbend10k@ yahoogroups. com, kgregg@ wrote:
                    > >
                    > > My heavy 10 sounds just like yours (i.e. it has a pin to locate
                    its
                    > > position on the bed). I first leveled the bed with a machinist's
                    > > level (very important). A previous owner hacked the bottom of
                    the
                    > > headstock for some reason so once I leveled the bed, I used a
                    > > combination of cutting test bars and running dial indicators to
                    > shim
                    > > under the headstock. Now that I have it perfect, I will
                    hopefully
                    > > never remove the headstock from the bed.
                    > >
                    > > -Kevin

                    .

                  • ALAN WHEATLEY
                    Chet Your lathe s alignment is probably as good as many members machines. You can get it to align better than half a thou if you have time and patience, and if
                    Message 9 of 16 , Sep 21, 2007
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                      Chet

                      Your lathe's alignment is probably as good as many members machines. You can get it to align better than half a thou if you have time and patience, and if your intended work demands a better standard.

                      If you just want to use the lathe to gain experience and new skills, to enjoy using it, and to fix some things around the house/car/model/etc, your lathe is already able to help you do this. When you are freshly into lathe work a machine like yours is able to do better work than you can easily manage -- so you can go ahead and enjoy it !

                      As time goes by you'll get better at using the lathe and you'll want to tackle more ambitious projects and larger size turning jobs, then you can put some more time into getting better alignment, and you'll be rewarded with an even better lathe.

                      Maybe it's time to start enjoying the first rewards.

                      Alan
                       
                       
                       
                      Chet R Biggerstaff wrote:

                      make that 5 ten thousandths in 5 inches

                      --- In southbend10k@ yahoogroups. com, "Chet R Biggerstaff" <Chet@...>
                      wrote:
                      >
                      > i just finished leveling the lathe and im within 1 thou in 5
                      inches
                      > with the 3jaw. Is this good or should i be able to get it all out?
                      >

                    • Chet R Biggerstaff
                      Thanks for the kind words but ive 4 lathes a micro mill I cnc ed, a large mill drill, drill press, and a shaper along with all the various bits that are needed
                      Message 10 of 16 , Sep 21, 2007
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                        Thanks for the kind words but ive 4 lathes a micro mill I cnc'ed, a
                        large mill drill, drill press, and a shaper along with all the
                        various bits that are needed with this. But im nowhere near being
                        proficent. Ill have lots o questions :)



                        --- In southbend10k@yahoogroups.com, ALAN WHEATLEY
                        <alan.wheatley10@...> wrote:
                        >
                        > Chet
                        >
                        > Your lathe's alignment is probably as good as many members
                        machines. You can get it to align better than half a thou if you have
                        time and patience, and if your intended work demands a better
                        standard.
                        >
                        > If you just want to use the lathe to gain experience and new
                        skills, to enjoy using it, and to fix some things around the
                        house/car/model/etc, your lathe is already able to help you do this.
                        When you are freshly into lathe work a machine like yours is able to
                        do better work than you can easily manage -- so you can go ahead and
                        enjoy it !
                        >
                        > As time goes by you'll get better at using the lathe and you'll
                        want to tackle more ambitious projects and larger size turning jobs,
                        then you can put some more time into getting better alignment, and
                        you'll be rewarded with an even better lathe.
                        >
                        > Maybe it's time to start enjoying the first rewards.
                        >
                        >
                        > Alan
                        >
                        >
                        >
                        > Chet R Biggerstaff wrote:
                        > make that 5 ten thousandths in 5 inches
                        >
                        > --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff" <Chet@>
                        > wrote:
                        > >
                        > > i just finished leveling the lathe and im within 1 thou in 5
                        > inches
                        > > with the 3jaw. Is this good or should i be able to get it all out?
                        > >
                        >
                      • Chet R Biggerstaff
                        btw its either a 5 or 6 cushman 3 jaw. I tore the wohle lathe down com,pletly when I got it, striped all the gook and paint off and repainted the whole unit.
                        Message 11 of 16 , Sep 21, 2007
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                          btw its either a 5 or 6" cushman 3 jaw. I tore the wohle lathe down
                          com,pletly when I got it, striped all the gook and paint off and
                          repainted the whole unit. Then lubed evey point replaced the felt
                          wipers with new felt. I also took the chuck apart cleaned and
                          polished up all the surfaces that were yucky (all of em heh) cleaned
                          the scroll and 3 pinions (even got em all back in the same slots) and
                          put it all back together. Worked much better....much smother..oh and
                          i did lube it before i put it back together. Have yet to hit the
                          tailstock alignment but will have to do it today as I need to turn
                          between venters today for a boring head without a tail im making.
                          Thanks


                          --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff" <Chet@...>
                          wrote:
                          >
                          > make that 5 ten thousandths in 5 inches
                          >
                          > --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff" <Chet@>
                          > wrote:
                          > >
                          > > i just finished leveling the lathe and im within 1 thou in 5
                          > inches
                          > > with the 3jaw. Is this good or should i be able to get it all out?
                          > >
                          > >
                          > > --- In southbend10k@yahoogroups.com, kgregg@ wrote:
                          > > >
                          > > > My heavy 10 sounds just like yours (i.e. it has a pin to locate
                          > its
                          > > > position on the bed). I first leveled the bed with a
                          machinist's
                          > > > level (very important). A previous owner hacked the bottom of
                          > the
                          > > > headstock for some reason so once I leveled the bed, I used a
                          > > > combination of cutting test bars and running dial indicators to
                          > > shim
                          > > > under the headstock. Now that I have it perfect, I will
                          > hopefully
                          > > > never remove the headstock from the bed.
                          > > >
                          > > > -Kevin
                          > > >
                          > > > ----- Original Message -----
                          > > > From: Chet R Biggerstaff <Chet@>
                          > > > Date: Thursday, September 20, 2007 1:15 pm
                          > > > Subject: [southbend10k] Re: Heavy 10 headstock alignment problem
                          > > > To: southbend10k@yahoogroups.com
                          > > >
                          > > > > turned a taper on the bar i cut it.
                          > > > >
                          > > > > --- In southbend10k@yahoogroups.com, "one2watch999" <mark@>
                          > wrote:
                          > > > > >
                          > > > > > Just to claer up my understanding - do you mean that you
                          have
                          > > > > turned a
                          > > > > > bar mounted in the 3 jaw and the one end is smaller than
                          the
                          > > the
                          > > > > other
                          > > > > > (turned a taper) or do you mean that measuring with a DTI
                          > > > > mounted
                          > > > > on
                          > > > > > the cross slide a plain round bar deviates along it's
                          length
                          > > > > (when
                          > > > > > mounted in the 3 jaw)?
                          > > > > >
                          > > > > > The reason I ask is that differences in turned diameters
                          > > > > indicate
                          > > > > > misalignement in the bed/lathe setup but deviations in an
                          un-
                          > > > > turned
                          > > > > > bar mounted in the chuck would probably be expected from
                          the
                          > > > > normal
                          > > > > > error found in a 3 Jaw (unless it has been trued at the
                          test
                          > > > > diameter -
                          > > > > > and even then it may not be gripping the stock concentric).
                          > > > > >
                          > > > > > When I set my Boxford, I used a machine level (I know this
                          is
                          > > > > > contentious but that is how I like to do it!) and a test
                          bar
                          > > > > with a
                          > > > > > suitable morse taper driven into the head. Works for me,
                          and
                          > > was
                          > > > > the
                          > > > > > way the machine fitters always set lathes up the shops I
                          > worked
                          > > > > > in/with.
                          > > > > >
                          > > > > > Regards
                          > > > > >
                          > > > > > Mark
                          > > > > >
                          > > > > > --- In southbend10k@yahoogroups.com, "Chet R Biggerstaff"
                          > > > > <Chet@>
                          > > > > > wrote:
                          > > > > > >
                          > > > > > > I have just bought a heavy 10 lathe and started testing
                          it
                          > to
                          > > > > see
                          > > > > > what
                          > > > > > > it needs. I have found that in the 3 jaw chuck with a
                          peice
                          > > of
                          > > > > 12l14
                          > > > > > > round stock sticking out 4.5" that it is 5 thou smaller
                          at
                          > > the
                          > > > > far
                          > > > > > end
                          > > > > > > (no tailstock support). The headstock is pined to the bed
                          > so
                          > > > > there
                          > > > > > does
                          > > > > > > not seem to be any adjustment to take this out. Any ideas?
                          > > > > > >
                          > > > > >
                          > > > >
                          > > > >
                          > > > >
                          > > >
                          > >
                          >
                        • Chris Strazzeri
                          Chet, somethings should be clarified here regarding your chuck accuracy questions. (1) As long as your chuck holds the stock securely, it s absolute dead
                          Message 12 of 16 , Sep 21, 2007
                          • 0 Attachment
                            Chet, somethings should be clarified here regarding your chuck accuracy questions.
                             
                            (1) As long as your chuck holds the stock securely, it's absolute dead center accuracy is irrelevant if the cuts you are making are not referenced to an unturned portion of the stock.
                             
                            (2) Dead center accuracy is important when (1) isn't true and when the raw stock diameter is such that you can't afford to lose much stock from truing it.
                             
                            Beyond those issues, unwanted tapers are predominantly a reflection of bed twist and bed wear. These two factors should be minimized before the tail stock is thrown into to mix, as they have their own set of issues.
                             
                            Is your bed Flame Hardened? I believe an 'X' in the serial no. would indicate this.
                             
                            Chris
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