Loading ...
Sorry, an error occurred while loading the content.
 

Re: [casting] Spincaster Plans (for casting pewter)

Expand Messages
  • Ted Quick
    OK, I ll see if I can explain. The turntable inside has a hollow drive shaft (pipe) under it. The motor is geared or v-belted to the base of the pipe. There is
    Message 1 of 15 , Feb 1, 2006
      OK, I'll see if I can explain. The turntable inside has a hollow drive shaft (pipe) under it. The
      motor is geared or v-belted to the base of the pipe. There is an air (aka pneumatic) cylinder
      below the open lower end of the pipe, with it's shaft going up inside the pipe, and it's base
      attached to a cross frame.

      At the top end of the cylinder's shaft is the floating platform that the mold sits on. There's
      another "spinning" plate under the floating plate that is attached to the top of the pipe. There
      are several arms on the spinning plate (usually 4, depending on size of unit) that look like
      telephone poles, with 2 or 3 cross arms near the top of each. Sort of a basket.

      Then there is a top plate that goes above the mold, with the appropriate number of horizontal pins
      spaced around it's edge so they will correspond to the telephone pole's positions. The top plate
      has a central hole in a built up center, which has a tapered hole in it for the metal to be poured
      through, into a central hole through the top half of the mold.

      So, the mold is placed on top of the floatin plate inside the basket that will be spinning it
      later. The top plate is placed on top of the mold with it's pins in between telephone poles, then
      turned until the pins are below cross arms at whichever level applies. The when the outside cover
      on the guard around the basket is lowered the air cylinder pushes up the floating plate, with the
      mold and top plate on it. Goes up until the edge pins lock under the phone pole cross arms, and
      starts to spin. The air cylinder holds pressure to keep the mold closed while spinning.

      Confused yet?

      Ted Quick


      --- J Jairo <deijairo@...> wrote:

      > Hi Everyone
      >
      > I have been a lurker on these boards for a while now.
      > I have been searching the net for some time now trying
      > to find plans for a spincaster. The exterior (bulk of
      > the machine is self expanitory however the interior
      > design is where I'm at a loss! Any info on this is
      > greatly appreciated thanks
      >
      > Adam
      >
      >
      >
      >
      >
      >
      > __________________________________________________________
      > Find your next car at http://autos.yahoo.ca
      >
      >
      >


      Ted Quick
    • Keith McCarron
      Adam, For an explanation of the process and diagrams of the setup and machine, look at http://www.contenti.com/products/spin-casting.html They show all.
      Message 2 of 15 , Feb 3, 2006
        Adam,

        For an explanation of the process and diagrams of the setup and
        machine, look at http://www.contenti.com/products/spin-casting.html

        They show all.

        Cheers,
        Keith



        --- In casting@yahoogroups.com, J Jairo <deijairo@...> wrote:
        >
        > Hi Everyone
        >
        > I have been a lurker on these boards for a while now.
        > I have been searching the net for some time now trying
        > to find plans for a spincaster. The exterior (bulk of
        > the machine is self expanitory however the interior
        > design is where I'm at a loss! Any info on this is
        > greatly appreciated thanks
        >
        > Adam
        >
        >
        >
        >
        >
        >
        > __________________________________________________________
        > Find your next car at http://autos.yahoo.ca
        >
      • lathe9x20
        Ted-- Thanks for the description. I have a question about how evenly the mold cavities fill. Consider a mold which makes four copies. Name the copies North,
        Message 3 of 15 , Feb 4, 2006
          Ted--

          Thanks for the description. I have a question about how evenly
          the mold cavities fill.

          Consider a mold which makes four copies. Name the copies North,
          South, East, and West.

          Unless the pour funnel on the top plate is EXACTLY CENTERED and
          has a very small bottom hole, some of the metal will be poured
          off-center, say .1 mm towards East. The distance from the center-of-
          rotation to East will be longer than the distance from the center to
          the other three cavities. Centrifical force to East will therefore be
          higher, and East will fill before the other three. What happens then?
          Does East overflow into the others? Doesn't the whole spincaster
          shake like the dickens when the mold is being poured?

          Or am I all wet? (it's happened before) Do all 4 fill evenly?

          The reason I ask is that if the spincaster shakes a lot because it is
          off-balance even for a moment, then any homebrew machine will have to
          be designed so that it can take the shaking.

          Comments? Any one else on the list want to comment?

          Thanks!

          John


          --- In casting@yahoogroups.com, Ted Quick <rim_molder@...> wrote:
          >
          > OK, I'll see if I can explain. The turntable inside has a hollow
          drive shaft (pipe) under it. The
          > motor is geared or v-belted to the base of the pipe. There is an air
          (aka pneumatic) cylinder
          > below the open lower end of the pipe, with it's shaft going up
          inside the pipe, and it's base
          > attached to a cross frame.
          >
          > At the top end of the cylinder's shaft is the floating platform that
          the mold sits on. There's
          > another "spinning" plate under the floating plate that is attached
          to the top of the pipe. There
          > are several arms on the spinning plate (usually 4, depending on size
          of unit) that look like
          > telephone poles, with 2 or 3 cross arms near the top of each. Sort
          of a basket.
          >
          > Then there is a top plate that goes above the mold, with the
          appropriate number of horizontal pins
          > spaced around it's edge so they will correspond to the telephone
          pole's positions. The top plate
          > has a central hole in a built up center, which has a tapered hole in
          it for the metal to be poured
          > through, into a central hole through the top half of the mold.
          >
          > So, the mold is placed on top of the floatin plate inside the basket
          that will be spinning it
          > later. The top plate is placed on top of the mold with it's pins in
          between telephone poles, then
          > turned until the pins are below cross arms at whichever level
          applies. The when the outside cover
          > on the guard around the basket is lowered the air cylinder pushes up
          the floating plate, with the
          > mold and top plate on it. Goes up until the edge pins lock under the
          phone pole cross arms, and
          > starts to spin. The air cylinder holds pressure to keep the mold
          closed while spinning.
          >
          > Confused yet?
          >
          > Ted Quick
          >
          >
          > --- J Jairo <deijairo@...> wrote:
          >
          > > Hi Everyone
          > >
          > > I have been a lurker on these boards for a while now.
          > > I have been searching the net for some time now trying
          > > to find plans for a spincaster. The exterior (bulk of
          > > the machine is self expanitory however the interior
          > > design is where I'm at a loss! Any info on this is
          > > greatly appreciated thanks
          > >
          > > Adam
          > >
          > >
          > >
          > >
          > >
          > >
          > > __________________________________________________________
          > > Find your next car at http://autos.yahoo.ca
          > >
          > >
          > >
          >
          >
          > Ted Quick
          >
        • Ted Quick
          OK, what you don t know about is that there is a ring or 2 set around the pour hole in the mold that changes the flow pattern somewhat. These rings are sold as
          Message 4 of 15 , Feb 5, 2006
            OK, what you don't know about is that there is a ring or 2 set around the pour hole in the mold
            that changes the flow pattern somewhat. These rings are sold as a regular accessory, usually with
            2 rings conneced with multiple legs all the way around. The metal has to go through these to in
            order leave slag trapped in them while clean metal, which flows better, will flow past.

            That doesn't necessarily solve the problem you mention, but will even things out somewhat if the
            runners from the center are different sizes, for instance. Anyway, the difference between cavities
            should only be enough to matter if your cavities are of VERY different sizes. If your mold is to
            make 1 much larger item and 3 smaller ones you might have enough difference to matter. MOST parts
            made in spincasters tend to be relatively small and the effects on balance are too slight to
            matter much. Good bearings for the turntable are necessary of course, and any homebuilt should
            design stronger rather than weaker supporting structure in to handle the worst possible load for a
            long time.

            Also note that the spinning will lessen the effect of an off center pour hole through the machine
            cover. Once it hits the bottom rubber mold half it will spin around to the sides evenly enough to
            displace any minor offset. Just center it correctly when you build it, or you'll tend to spray
            metal around inside the shroud that doesn't enter the pour hole through the top metal cover plate
            of the mold....

            I trust you understand there MUST be a sheet metal can around the mold basket, with a flip open
            lid with a limit switch that it truns on when it's closed. This switch starts the motor spinning
            the mold for safety purposes, and the metal shroud keeps any and all hot metal from spraying the
            room and you.

            Ted Quick

            --- lathe9x20 <lathe9x20@...> wrote:
            > Thanks for the description. I have a question about how evenly
            > the mold cavities fill.
            >
            > Consider a mold which makes four copies. Name the copies North,
            > South, East, and West.
            >
            > Unless the pour funnel on the top plate is EXACTLY CENTERED and
            > has a very small bottom hole, some of the metal will be poured
            > off-center, say .1 mm towards East. The distance from the center-of-
            > rotation to East will be longer than the distance from the center to
            > the other three cavities. Centrifical force to East will therefore be
            > higher, and East will fill before the other three. What happens then?
            > Does East overflow into the others? Doesn't the whole spincaster
            > shake like the dickens when the mold is being poured?
            >
            > Or am I all wet? (it's happened before) Do all 4 fill evenly?
            >
            > The reason I ask is that if the spincaster shakes a lot because it is
            > off-balance even for a moment, then any homebrew machine will have to
            > be designed so that it can take the shaking.
            >
            > Comments? Any one else on the list want to comment?
            >
            > Thanks!
            >
            > John
            >
            >
            > --- In casting@yahoogroups.com, Ted Quick <rim_molder@...> wrote:
            > >
            > > OK, I'll see if I can explain. The turntable inside has a hollow
            > drive shaft (pipe) under it. The
            > > motor is geared or v-belted to the base of the pipe. There is an air
            > (aka pneumatic) cylinder
            > > below the open lower end of the pipe, with it's shaft going up
            > inside the pipe, and it's base
            > > attached to a cross frame.
            > >
            > > At the top end of the cylinder's shaft is the floating platform that
            > the mold sits on. There's
            > > another "spinning" plate under the floating plate that is attached
            > to the top of the pipe. There
            > > are several arms on the spinning plate (usually 4, depending on size
            > of unit) that look like
            > > telephone poles, with 2 or 3 cross arms near the top of each. Sort
            > of a basket.
            > >
            > > Then there is a top plate that goes above the mold, with the
            > appropriate number of horizontal pins
            > > spaced around it's edge so they will correspond to the telephone
            > pole's positions. The top plate
            > > has a central hole in a built up center, which has a tapered hole in
            > it for the metal to be poured
            > > through, into a central hole through the top half of the mold.
            > >
            > > So, the mold is placed on top of the floatin plate inside the basket
            > that will be spinning it
            > > later. The top plate is placed on top of the mold with it's pins in
            > between telephone poles, then
            > > turned until the pins are below cross arms at whichever level
            > applies. The when the outside cover
            > > on the guard around the basket is lowered the air cylinder pushes up
            > the floating plate, with the
            > > mold and top plate on it. Goes up until the edge pins lock under the
            > phone pole cross arms, and
            > > starts to spin. The air cylinder holds pressure to keep the mold
            > closed while spinning.
            > >
            > > Confused yet?
            > >
            > > Ted Quick
            > >
            > >
            > > --- J Jairo <deijairo@...> wrote:
            > >
            > > > Hi Everyone
            > > >
            > > > I have been a lurker on these boards for a while now.
            > > > I have been searching the net for some time now trying
            > > > to find plans for a spincaster. The exterior (bulk of
            > > > the machine is self expanitory however the interior
            > > > design is where I'm at a loss! Any info on this is
            > > > greatly appreciated thanks
            > > >
            > > > Adam
            > > >
            > > >
            > > >
            > > >
            > > >
            > > >
            > > > __________________________________________________________
            > > > Find your next car at http://autos.yahoo.ca
            > > >
            > > >
            > > >
            > >
            > >
            > > Ted Quick
            > >
            >
            >
            >
            >
            >
          • lathe9x20
            Thanks again for the explanation, Ted. From what you ve said, I don t think the pneumatics are really necessary to open and lock the mold. A simple plate on
            Message 5 of 15 , Feb 7, 2006
              Thanks again for the explanation, Ted.

              From what you've said, I don't think the pneumatics are really
              necessary to open and lock the mold. A simple plate on which the
              circular mold fits and a through-bolted cover plate should do the
              trick. Of course, air-operated tools are much quicker so are needed in
              high production shops.

              The device you are describing seems a lot like an old top-loading
              washing machine with the agitator removed, a horizonal plate fixed
              inside the tub and a pour spout drilled and fitted in the lid.

              Washing machines already have the motor and gearing to spin quickly,
              have a tub covered in sheet metal, and are made to handle unbalanced
              loads. Old machines with bad main bearings are avaliable for
              near-free because the labor cost to disassemble everything to get to
              the bearing is too near the price of a new machine. A hobbyist could
              dissassemble one and fix it with the very good instructions available
              at www.repairclinic.com or www.applianceaid.com. (I've dealt with the
              former, and have only seen adds by the latter).

              Thanks again for the long explanations.

              John

              --- In casting@yahoogroups.com, Ted Quick <rim_molder@...> wrote:
              >
              > OK, what you don't know about is that there is a ring or 2 set
              around the pour hole in the mold
              > that changes the flow pattern somewhat. These rings are sold as a
              regular accessory, usually with
              > 2 rings conneced with multiple legs all the way around. The metal
              has to go through these to in
              > order leave slag trapped in them while clean metal, which flows
              better, will flow past.
              >
              > That doesn't necessarily solve the problem you mention, but will
              even things out somewhat if the
              > runners from the center are different sizes, for instance. Anyway,
              the difference between cavities
              > should only be enough to matter if your cavities are of VERY
              different sizes. If your mold is to
              > make 1 much larger item and 3 smaller ones you might have enough
              difference to matter. MOST parts
              > made in spincasters tend to be relatively small and the effects on
              balance are too slight to
              > matter much. Good bearings for the turntable are necessary of
              course, and any homebuilt should
              > design stronger rather than weaker supporting structure in to handle
              the worst possible load for a
              > long time.
              >
              > Also note that the spinning will lessen the effect of an off center
              pour hole through the machine
              > cover. Once it hits the bottom rubber mold half it will spin around
              to the sides evenly enough to
              > displace any minor offset. Just center it correctly when you build
              it, or you'll tend to spray
              > metal around inside the shroud that doesn't enter the pour hole
              through the top metal cover plate
              > of the mold....
              >
              > I trust you understand there MUST be a sheet metal can around the
              mold basket, with a flip open
              > lid with a limit switch that it truns on when it's closed. This
              switch starts the motor spinning
              > the mold for safety purposes, and the metal shroud keeps any and all
              hot metal from spraying the
              > room and you.
              >
              > Ted Quick
              >
              > --- lathe9x20 <lathe9x20@...> wrote:
              > > Thanks for the description. I have a question about how evenly
              > > the mold cavities fill.
              > >
              > > Consider a mold which makes four copies. Name the copies North,
              > > South, East, and West.
              > >
              > > Unless the pour funnel on the top plate is EXACTLY CENTERED and
              > > has a very small bottom hole, some of the metal will be poured
              > > off-center, say .1 mm towards East. The distance from the center-of-
              > > rotation to East will be longer than the distance from the center to
              > > the other three cavities. Centrifical force to East will therefore be
              > > higher, and East will fill before the other three. What happens then?
              > > Does East overflow into the others? Doesn't the whole spincaster
              > > shake like the dickens when the mold is being poured?
              > >
              > > Or am I all wet? (it's happened before) Do all 4 fill evenly?
              > >
              > > The reason I ask is that if the spincaster shakes a lot because it is
              > > off-balance even for a moment, then any homebrew machine will have to
              > > be designed so that it can take the shaking.
              > >
              > > Comments? Any one else on the list want to comment?
              > >
              > > Thanks!
              > >
              > > John
              > >
              > >
              > > --- In casting@yahoogroups.com, Ted Quick <rim_molder@> wrote:
              > > >
              > > > OK, I'll see if I can explain. The turntable inside has a hollow
              > > drive shaft (pipe) under it. The
              > > > motor is geared or v-belted to the base of the pipe. There is an air
              > > (aka pneumatic) cylinder
              > > > below the open lower end of the pipe, with it's shaft going up
              > > inside the pipe, and it's base
              > > > attached to a cross frame.
              > > >
              > > > At the top end of the cylinder's shaft is the floating platform that
              > > the mold sits on. There's
              > > > another "spinning" plate under the floating plate that is attached
              > > to the top of the pipe. There
              > > > are several arms on the spinning plate (usually 4, depending on size
              > > of unit) that look like
              > > > telephone poles, with 2 or 3 cross arms near the top of each. Sort
              > > of a basket.
              > > >
              > > > Then there is a top plate that goes above the mold, with the
              > > appropriate number of horizontal pins
              > > > spaced around it's edge so they will correspond to the telephone
              > > pole's positions. The top plate
              > > > has a central hole in a built up center, which has a tapered hole in
              > > it for the metal to be poured
              > > > through, into a central hole through the top half of the mold.
              > > >
              > > > So, the mold is placed on top of the floatin plate inside the basket
              > > that will be spinning it
              > > > later. The top plate is placed on top of the mold with it's pins in
              > > between telephone poles, then
              > > > turned until the pins are below cross arms at whichever level
              > > applies. The when the outside cover
              > > > on the guard around the basket is lowered the air cylinder pushes up
              > > the floating plate, with the
              > > > mold and top plate on it. Goes up until the edge pins lock under the
              > > phone pole cross arms, and
              > > > starts to spin. The air cylinder holds pressure to keep the mold
              > > closed while spinning.
              > > >
              > > > Confused yet?
              > > >
              > > > Ted Quick
              > > >
              > > >
              > > > --- J Jairo <deijairo@> wrote:
              > > >
              > > > > Hi Everyone
              > > > >
              > > > > I have been a lurker on these boards for a while now.
              > > > > I have been searching the net for some time now trying
              > > > > to find plans for a spincaster. The exterior (bulk of
              > > > > the machine is self expanitory however the interior
              > > > > design is where I'm at a loss! Any info on this is
              > > > > greatly appreciated thanks
              > > > >
              > > > > Adam
              > > > >
              > > > >
              > > > >
              > > > >
              > > > >
              > > > >
              > > > > __________________________________________________________
              > > > > Find your next car at http://autos.yahoo.ca
              > > > >
              > > > >
              > > > >
              > > >
              > > >
              > > > Ted Quick
              > > >
              > >
              > >
              > >
              > >
              > >
              >
            • Ted Quick
              ... You re quite welcome. ... True, though the pneumatic cylinder may have advantages, since bolts may be tightened more or less each time and the air cylinder
              Message 6 of 15 , Feb 8, 2006
                --- lathe9x20 <lathe9x20@...> wrote:
                > Thanks again for the explanation, Ted.

                You're quite welcome.

                > From what you've said, I don't think the pneumatics are really
                > necessary to open and lock the mold. A simple plate on which the
                > circular mold fits and a through-bolted cover plate should do the
                > trick. Of course, air-operated tools are much quicker so are needed in
                > high production shops.

                True, though the pneumatic cylinder may have advantages, since bolts may be tightened more or less
                each time and the air cylinder may be self adjusting when the heat hits the mold rubber and
                expands it (I guess). Probably not really since the cycle is too fast for that to matter.

                > The device you are describing seems a lot like an old top-loading
                > washing machine with the agitator removed, a horizonal plate fixed
                > inside the tub and a pour spout drilled and fitted in the lid.

                Makes sense to me. The pour spout, BTW, is best made of ceramic as sold by TekCast.

                Ted Quick
              • lathe9x20
                ... ... may be tightened more or less ... hits the mold rubber and ... For the production rates the hobbyist would need, (s)he could tighten the bolts
                Message 7 of 15 , Feb 8, 2006
                  --- In casting@yahoogroups.com, Ted Quick <rim_molder@...> wrote:
                  <snip>
                  >
                  > > From what you've said, I don't think the pneumatics are really
                  > > necessary to open and lock the mold. A simple plate on which the
                  > > circular mold fits and a through-bolted cover plate should do the
                  > > trick. Of course, air-operated tools are much quicker so are needed in
                  > > high production shops.
                  >
                  > True, though the pneumatic cylinder may have advantages, since bolts
                  may be tightened more or less
                  > each time and the air cylinder may be self adjusting when the heat
                  hits the mold rubber and
                  > expands it (I guess).

                  For the production rates the hobbyist would need, (s)he could tighten
                  the bolts with a torque wrench to make the pressure even every time.

                  I think I'd use long bolts through both the upper and lower plates,
                  tightened with wing nuts above the upper plate. Between the wingnut
                  and the plate would be a spring, like an automotive valve spring.
                  And the bolt would be buggered at some point to prove a stop so that
                  the wingnut(s) could only be screwed down that far, no matter how much
                  you torqued them. The spring under them would provide repeatable
                  pressure as long as the mold ring was the same diameter from
                  cast-to-cast, the same thickness of rubber pad were used, and the wing
                  nuts were all tightened down to their stops.

                  Hummm...maybe a torque wrench would be bettter afterall...much more
                  flexible.... The user could make sure all bolts were tighten evenly,
                  even if they were tightened too much or too little!

                  <snip>

                  > > The device you are describing seems a lot like an old top-loading
                  > > washing machine with the agitator removed, a horizonal plate fixed
                  > > inside the tub and a pour spout drilled and fitted in the lid.
                  >
                  > Makes sense to me. The pour spout, BTW, is best made of ceramic as
                  sold by TekCast.
                  >
                  > Ted Quick
                  >
                  I thought as much. The cost of a few accessories are unavoidable.
                  The design of the pour spout and slag catcher are critical, so these
                  are better bought.

                  JohnL
                • Paty
                  It might be easier to just use stripper bolts, they are made with the threads smaller than the shank and a prominent step where they meet. Just tighten the
                  Message 8 of 15 , Feb 8, 2006
                    It might be easier to just use stripper bolts, they are made with the threads smaller than the shank and a prominent step where they meet.

                    Just tighten the bolt to the step and they should all be at the same position.

                    ----- Original Message -----
                    From: lathe9x20
                    To: casting@yahoogroups.com
                    Sent: Wednesday, February 08, 2006 12:25 PM
                    Subject: [casting] Re: Washing Machine Spin Caster Was: Spincaster Plans (for casting pewter)


                    --- In casting@yahoogroups.com, Ted Quick <rim_molder@...> wrote:
                    <snip>
                    >
                    > > From what you've said, I don't think the pneumatics are really
                    > > necessary to open and lock the mold. A simple plate on which the
                    > > circular mold fits and a through-bolted cover plate should do the
                    > > trick. Of course, air-operated tools are much quicker so are needed in
                    > > high production shops.
                    >
                    > True, though the pneumatic cylinder may have advantages, since bolts
                    may be tightened more or less
                    > each time and the air cylinder may be self adjusting when the heat
                    hits the mold rubber and
                    > expands it (I guess).

                    For the production rates the hobbyist would need, (s)he could tighten
                    the bolts with a torque wrench to make the pressure even every time.

                    I think I'd use long bolts through both the upper and lower plates,
                    tightened with wing nuts above the upper plate. Between the wingnut
                    and the plate would be a spring, like an automotive valve spring.
                    And the bolt would be buggered at some point to prove a stop so that
                    the wingnut(s) could only be screwed down that far, no matter how much
                    you torqued them. The spring under them would provide repeatable
                    pressure as long as the mold ring was the same diameter from
                    cast-to-cast, the same thickness of rubber pad were used, and the wing
                    nuts were all tightened down to their stops.

                    Hummm...maybe a torque wrench would be bettter afterall...much more
                    flexible.... The user could make sure all bolts were tighten evenly,
                    even if they were tightened too much or too little!

                    <snip>

                    > > The device you are describing seems a lot like an old top-loading
                    > > washing machine with the agitator removed, a horizonal plate fixed
                    > > inside the tub and a pour spout drilled and fitted in the lid.
                    >
                    > Makes sense to me. The pour spout, BTW, is best made of ceramic as
                    sold by TekCast.
                    >
                    > Ted Quick
                    >
                    I thought as much. The cost of a few accessories are unavoidable.
                    The design of the pour spout and slag catcher are critical, so these
                    are better bought.

                    JohnL





                    SPONSORED LINKS Casting Hobby and craft supply Craft hobby
                    Casting mold


                    ------------------------------------------------------------------------------
                    YAHOO! GROUPS LINKS

                    a.. Visit your group "casting" on the web.

                    b.. To unsubscribe from this group, send an email to:
                    casting-unsubscribe@yahoogroups.com

                    c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.


                    ------------------------------------------------------------------------------



                    [Non-text portions of this message have been removed]
                  • lathe9x20
                    ... the threads smaller than the shank and a prominent step where they meet. ... position. Yes, but those bolts are availabe in a very limited number of
                    Message 9 of 15 , Feb 9, 2006
                      --- In casting@yahoogroups.com, "Paty" <patyr@...> wrote:
                      >
                      > It might be easier to just use stripper bolts, they are made with
                      the threads smaller than the shank and a prominent step where they meet.
                      >
                      > Just tighten the bolt to the step and they should all be at the same
                      position.

                      <snip>

                      Yes, but those bolts are availabe in a very limited number of lengths.
                      The problem with bolt-with-stops is that they are not adjustable for
                      different mold thicknesses. If you really wanted to use stripper
                      bolts but none were available of the right lenght, you could use a
                      regular bolt/wingnut and cut some metal tubing (like electrical
                      conduit, or 1/8" pipe) to the right length to slip over the bolt.
                      That would make a homemade stripper bolt for our puposes. Cut
                      different lenghts of tubes for different tightnessed needed and/or for
                      different thicknesses of mold.
                      Each "set" of tubes would be made up of 4 equal-length tubes if 4
                      bolts were used to hold the upper plate, mold, and bottom plate together.

                      JohnL
                      > For the production rates the hobbyist would need, (s)he could tighten
                      > the bolts with a torque wrench to make the pressure even every time.
                      >
                      > I think I'd use long bolts through both the upper and lower plates,
                      > tightened with wing nuts above the upper plate. Between the wingnut
                      > and the plate would be a spring, like an automotive valve spring.
                      > And the bolt would be buggered at some point to prove a stop so that
                      > the wingnut(s) could only be screwed down that far, no matter how much
                      > you torqued them. The spring under them would provide repeatable
                      > pressure as long as the mold ring was the same diameter from
                      > cast-to-cast, the same thickness of rubber pad were used, and the wing
                      > nuts were all tightened down to their stops.
                      >
                      > Hummm...maybe a torque wrench would be bettter afterall...much more
                      > flexible.... The user could make sure all bolts were tighten evenly,
                      > even if they were tightened too much or too little!
                      >
                      > <snip>
                      >
                      >
                    • Steve Freshour
                      problem with wingnuts they strip easy. just use a fiber locknut and they usually dont move. and some places you can find plastic wingnuts that work with fiber
                      Message 10 of 15 , Feb 9, 2006
                        problem with wingnuts they strip easy. just use a fiber locknut and they
                        usually dont move.
                        and some places you can find plastic wingnuts that work with fiber locknuts
                        as handles.

                        Steve
                      • REDROCKET
                        Hello, Can anyone tell me what kind of resin was used to cast this: http://www.87thscale.info/images/DW_Miura.jpg I use clear resin and I tint white Polytek.
                        Message 11 of 15 , Feb 10, 2006
                          Hello,

                          Can anyone tell me what kind of resin was used to cast this:

                          http://www.87thscale.info/images/DW_Miura.jpg

                          I use clear resin and I tint white Polytek.

                          Thanks

                          Mac

                          PS also I have the sculptures from china. They are cheap from the $1 store.
                          They say they are made of Poly stone. Kind of a ceramic feel but obviously
                          cast. Any ideas.
                        • Ray K.
                          Smooth-on s SC 325, 326 or 327 possibly, but there are JILLIONS of resins out there like that. Ray Kotke www.telephonecreations.com ... From: REDROCKET
                          Message 12 of 15 , Feb 10, 2006
                            Smooth-on's SC 325, 326 or 327 possibly, but there are JILLIONS of resins
                            out there like that.

                            Ray Kotke
                            www.telephonecreations.com

                            ----- Original Message -----
                            From: "REDROCKET" <redrocket@...>
                            To: <casting@yahoogroups.com>
                            Sent: Friday, February 10, 2006 1:47 PM
                            Subject: [casting] What type of resin is this?


                            > Hello,
                            >
                            > Can anyone tell me what kind of resin was used to cast this:
                            >
                            > http://www.87thscale.info/images/DW_Miura.jpg
                            >
                            > I use clear resin and I tint white Polytek.
                            >
                            > Thanks
                            >
                            > Mac
                            >
                            > PS also I have the sculptures from china. They are cheap from the $1
                            store.
                            > They say they are made of Poly stone. Kind of a ceramic feel but obviously
                            > cast. Any ideas.
                            >
                            >
                            >
                            >
                            >
                            > Yahoo! Groups Links
                            >
                            >
                            >
                            >
                            >
                            >
                            >
                            >
                          • N Hill
                            Also looks a bit like Smooth-on s Vitaflex 20 urethane. Regards, Carl www.gatehousecandles.com ... From: Ray K. To: casting@yahoogroups.com Sent: Friday,
                            Message 13 of 15 , Feb 10, 2006
                              Also looks a bit like Smooth-on's Vitaflex 20 urethane.

                              Regards,
                              Carl

                              www.gatehousecandles.com
                              ----- Original Message -----
                              From: Ray K.
                              To: casting@yahoogroups.com
                              Sent: Friday, February 10, 2006 2:22 PM
                              Subject: Re: [casting] What type of resin is this?


                              Smooth-on's SC 325, 326 or 327 possibly, but there are JILLIONS of resins
                              out there like that.

                              Ray Kotke
                              www.telephonecreations.com

                              ----- Original Message -----
                              From: "REDROCKET" <redrocket@...>
                              To: <casting@yahoogroups.com>
                              Sent: Friday, February 10, 2006 1:47 PM
                              Subject: [casting] What type of resin is this?


                              > Hello,
                              >
                              > Can anyone tell me what kind of resin was used to cast this:
                              >
                              > http://www.87thscale.info/images/DW_Miura.jpg
                              >
                              > I use clear resin and I tint white Polytek.
                              >
                              > Thanks
                              >
                              > Mac
                              >
                              > PS also I have the sculptures from china. They are cheap from the $1
                              store.
                              > They say they are made of Poly stone. Kind of a ceramic feel but obviously
                              > cast. Any ideas.
                              >
                              >
                              >
                              >
                              >
                              > Yahoo! Groups Links
                              >
                              >
                              >
                              >
                              >
                              >
                              >
                              >



                              SPONSORED LINKS Casting Hobby and craft supply Craft hobby
                              Casting mold


                              ------------------------------------------------------------------------------
                              YAHOO! GROUPS LINKS

                              a.. Visit your group "casting" on the web.

                              b.. To unsubscribe from this group, send an email to:
                              casting-unsubscribe@yahoogroups.com

                              c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.


                              ------------------------------------------------------------------------------



                              [Non-text portions of this message have been removed]
                            • Sculpt
                              Mac, It looks like a polyurethane, but there are many manufacturers that make a transparent amber. It could be any of them. -- Marc Fields The Compleat
                              Message 14 of 15 , Feb 11, 2006
                                Mac,
                                It looks like a polyurethane, but there are many manufacturers that make
                                a transparent amber. It could be any of them.

                                --
                                Marc Fields
                                The Compleat Sculptor, Inc.
                                "You Supply the Talent, We'll Supply the Rest."
                                212-367-7561 www.sculpt.com

                                CONFIDENTIALITY NOTICE:
                                This e-mail is confidential and privileged. If you have received it in error, please notify us immediately by reply e-mail and then delete this message from your system. Please do not copy it or disclose its contents to any other person. Thank you for your cooperation.
                              Your message has been successfully submitted and would be delivered to recipients shortly.