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Re: [multimachine] Re: HAPPY WORKERS DAY FOR ALL

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  • Benjamin Bof
    Friends; think in submersed arc using calcium carbonate as flux. This way CO2 is fired by arc contributing to maintain it and dont generating any kind of
    Message 1 of 18 , May 3, 2009
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      Friends; think in submersed arc using calcium carbonate as flux.
      This way CO2 is fired by arc contributing to maintain it
      and dont generating any kind of pollution.
      Regards, Ben
      On Sun, May 3, 2009 at 4:58 PM, Pierre Coueffin <pcoueffin@...> wrote:


      > Just as a point to ponder, if the furnace is to be filed with an inert
      > gas (like argon) which is conducive to ionization, why not a TIG type
      > arc to the metal surface? A ball ended tungsten electrode is fairly
      > inert and is not high tech magic. The biggest issue is the need for DC
      > and/or RF to get it running.

      Would we get enough tungsten contamination in a multiple-pound melt
      for scratch-start to not be an option? I suspect that you'd want
      several electrodes since a little 3/32 TIG electrode might not carry
      enough current...

      The other problem I can see is that TIG has the smallest heat affected
      zone of any welding process that I'm familiar with. To cast metal, we
      really need to spread the heat throughout the entire charge of metal,
      instead of concentrating it into a small part of the melt.

      My third problem is the one Vereecke alluded to: What equipment to
      use. I have two electric welders: One a new inverter TIG/Arc/Plasma
      combo unit I bought a few months ago, but it will only deliver 160
      amps. It is a cute little thing though, and nicely portable for going
      over to a friend's house to weld junk together. It would not be
      powerful enough to cast anything really useful though. My other one
      is a big old arc welder that my grandfather made from scratch in the
      early 1930's... It will deliver 400 amps. It is basically a 150
      pound transformer with multiple taps on the secondary coil to set the
      output current (and presumably voltage...) I need to do some work on
      it though, since the wiring on the transformer is all cloth insulated
      and is starting to rot. I have a carbon-arc torch head for it which
      holds two carbon rods and lets you adjust the spacing between them
      using a knob on the side. If I build a box out of firebrick and stuck
      the carbon rods inside, I suspect that anything inside the box would
      rapidly get very hot when I start the arc. Hooking up a fitting to
      feed a stream of Argon from my TIG tank (via the flow-control valve)
      into the box would certainly help to keep from oxidizing the melt, but
      I don't know what it would do to the arc itself. I think I might need
      to experiment a bit with the possibilities here. My big welder is out
      at the lake, where my parents are busy building a new house, and I'd
      have to do a bunch of work to render it safe to use again. I can
      probably use a friend's 300 amp buzz box for the experiment though, I
      have the TIG setup here, and the carbon-arc torch head is in my
      basement somewhere...


    • David LeVine
      ... Big electrodes or multiple electrodes sound like a good option, but starting one big electrode is easier. ... HAZ is not an issue, TIG concentrates the
      Message 2 of 18 , May 3, 2009
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        Pierre Coueffin wrote:
        >> Just as a point to ponder, if the furnace is to be filed with an inert
        >> gas (like argon) which is conducive to ionization, why not a TIG type
        >> arc to the metal surface? A ball ended tungsten electrode is fairly
        >> inert and is not high tech magic. The biggest issue is the need for DC
        >> and/or RF to get it running.
        >>
        >
        > Would we get enough tungsten contamination in a multiple-pound melt
        > for scratch-start to not be an option? I suspect that you'd want
        > several electrodes since a little 3/32 TIG electrode might not carry
        > enough current...
        >

        Big electrodes or multiple electrodes sound like a good option, but
        starting one big electrode is easier.

        > The other problem I can see is that TIG has the smallest heat affected
        > zone of any welding process that I'm familiar with. To cast metal, we
        > really need to spread the heat throughout the entire charge of metal,
        > instead of concentrating it into a small part of the melt.
        >

        HAZ is not an issue, TIG concentrates the heat at the point the plasma
        hits. Once the heat is in the metal it will spread...

        Scratch start on a copper block is often used. There is little (or no)
        contamination of the weld.

        > My third problem is the one Vereecke alluded to: What equipment to
        > use. I have two electric welders: One a new inverter TIG/Arc/Plasma
        > combo unit I bought a few months ago, but it will only deliver 160
        > amps. It is a cute little thing though, and nicely portable for going
        > over to a friend's house to weld junk together. It would not be
        > powerful enough to cast anything really useful though. My other one
        > is a big old arc welder that my grandfather made from scratch in the
        > early 1930's... It will deliver 400 amps. It is basically a 150
        > pound transformer with multiple taps on the secondary coil to set the
        > output current (and presumably voltage...) I need to do some work on
        > it though, since the wiring on the transformer is all cloth insulated
        > and is starting to rot. I have a carbon-arc torch head for it which
        > holds two carbon rods and lets you adjust the spacing between them
        > using a knob on the side. If I build a box out of firebrick and stuck
        > the carbon rods inside, I suspect that anything inside the box would
        > rapidly get very hot when I start the arc. Hooking up a fitting to
        > feed a stream of Argon from my TIG tank (via the flow-control valve)
        > into the box would certainly help to keep from oxidizing the melt, but
        > I don't know what it would do to the arc itself. I think I might need
        > to experiment a bit with the possibilities here. My big welder is out
        > at the lake, where my parents are busy building a new house, and I'd
        > have to do a bunch of work to render it safe to use again. I can
        > probably use a friend's 300 amp buzz box for the experiment though, I
        > have the TIG setup here, and the carbon-arc torch head is in my
        > basement somewhere...

        Just beware, carbon arcs generate a lot of UV. I don't know what
        happens to a carbon arc in argon either.

        --
        David G. LeVine
        Nashua, NH 03060
      • Eric Smith
        hehe, I AM a bit of a metallurgy expert. Propane is FULLY capable of melting iron. It s not as easy to achieve those temperatures, but it can be done. An
        Message 3 of 18 , May 3, 2009
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          hehe, I AM a bit of a metallurgy expert.
          Propane is FULLY capable of melting iron.
          It's not as easy to achieve those temperatures, but it can be done.

          An easier, and some would say more dangerous, method is to use thermite welding technology to melt the iron. You'd have to do some research, but basically, you mix alu powder, and iron powder, light it off and run. when the smoke and flame stop, you've got a cooling mass of steel/iron.

          Cast iron(grey iron) melts around 1150 to 1200°C
          Naturally aspirated propane furnaces usually hit around 1200°C, but to actually cast iron, you need it much hotter than just "starting to melt". With a custom setup, and a large forced air system, I've seen propane temperatures closing in on 1600°C which is plenty hot.

          ONE large truck turbo should provide plenty of oomph for a small iron melting furnace. As for casting anvils though.... I've done it. Iron, and steel castings. If anyone asked me for another anvil, I can tell you, it would either be reconditioned, or I'd weld it together from heavy plate. MUCH simpler.

          My personal anvil is an old 500 pounder. the face was messed up, so I machined it(well, ground down actually), and resurfaced it using hard face surfacing mig wire.

          However you look at it, a "real" anvil is gonna be hard to make.
          Best to find what you can locally, and modify it. Provided you can get it legally, Railroad rail can make a serviceable anvil. Cut, shaped, and polished... they make a nice light, utility anvil.

          --- In multimachine@yahoogroups.com, "cvlac" <cvlac0@...> wrote:
          >
          > Hi Ben
          > I'm not a metallurgist expert, but I think that you can't archive too hight temperatures with a propane burning furnace.Its Ok for alu, brass, but I do not think for iron and steel.Maybe you must select a better combustible (like diesel).
          > Costas
          >
          >
          > --- In multimachine@yahoogroups.com, "Benjamin Domingo Bof" <benjaminbof@> wrote:
          > >
          > > My idea is to build some multimachine in Brazil an becomes representant of this third world project. I can add welding electrodes, vise bench production now.
          > > But my drem is to make an iron and steel furnace by menas two series truck turbo blowers using propane gas bottle. Also to cast anvils using aluminothermy and perhaps graphite cricuibles because tyre repair shops uses graphite and is not expensive.
          > > Again; happy workers day for all members and moderator Pat Delany.
          > > Regards, Ben
          > >
          >
        • cvlac
          Hi Eric Thanks about all of this useful information.My problem here , in my place, is that it is hard to find low cost propane to use it for this purpose. I
          Message 4 of 18 , May 4, 2009
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            Hi Eric
            Thanks about all of this useful information.My problem here , in my place, is that it is hard to find low cost propane to use it for this
            purpose. I can only find small bottles used to weld copper tubes . And they cost a lot of euros.And as Ben says it is always cheaper to
            use coal as combustible.
            Costas

            --- In multimachine@yahoogroups.com, "Eric Smith" <white_knight_411@...> wrote:
            >
            > hehe, I AM a bit of a metallurgy expert.
            > Propane is FULLY capable of melting iron.
            > It's not as easy to achieve those temperatures, but it can be done.
            >
            > An easier, and some would say more dangerous, method is to use thermite welding technology to melt the iron. You'd have to do some research, but basically, you mix alu powder, and iron powder, light it off and run. when the smoke and flame stop, you've got a cooling mass of steel/iron.
            >
            > Cast iron(grey iron) melts around 1150 to 1200°C
            > Naturally aspirated propane furnaces usually hit around 1200°C, but to actually cast iron, you need it much hotter than just "starting to melt". With a custom setup, and a large forced air system, I've seen propane temperatures closing in on 1600°C which is plenty hot.
            >
            > ONE large truck turbo should provide plenty of oomph for a small iron melting furnace. As for casting anvils though.... I've done it. Iron, and steel castings. If anyone asked me for another anvil, I can tell you, it would either be reconditioned, or I'd weld it together from heavy plate. MUCH simpler.
            >
            > My personal anvil is an old 500 pounder. the face was messed up, so I machined it(well, ground down actually), and resurfaced it using hard face surfacing mig wire.
            >
            > However you look at it, a "real" anvil is gonna be hard to make.
            > Best to find what you can locally, and modify it. Provided you can get it legally, Railroad rail can make a serviceable anvil. Cut, shaped, and polished... they make a nice light, utility anvil.
            >
            > --- In multimachine@yahoogroups.com, "cvlac" <cvlac0@> wrote:
            > >
            > > Hi Ben
            > > I'm not a metallurgist expert, but I think that you can't archive too hight temperatures with a propane burning furnace.Its Ok for alu, brass, but I do not think for iron and steel.Maybe you must select a better combustible (like diesel).
            > > Costas
            > >
            > >
            > > --- In multimachine@yahoogroups.com, "Benjamin Domingo Bof" <benjaminbof@> wrote:
            > > >
            > > > My idea is to build some multimachine in Brazil an becomes representant of this third world project. I can add welding electrodes, vise bench production now.
            > > > But my drem is to make an iron and steel furnace by menas two series truck turbo blowers using propane gas bottle. Also to cast anvils using aluminothermy and perhaps graphite cricuibles because tyre repair shops uses graphite and is not expensive.
            > > > Again; happy workers day for all members and moderator Pat Delany.
            > > > Regards, Ben
            > > >
            > >
            >
          • Brian R. Wood
            I heard somewhere that they use huge solar reflectors in India to smelt steel, but I can t currently find anything on it so it may have been a myth. There was
            Message 5 of 18 , May 4, 2009
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              I heard somewhere that they use huge solar reflectors in India to smelt
              steel, but I can't currently find anything on it so it may have been a
              myth. There was a story on the internet of a guy using a big parabolic
              mirror on an old pickup frame (for tracking purposes) to demonstrate the
              power of the sun. (Solar Forge).
              http://www.charm.net/~jriley/energy/solarforge.html He ran out of money
              before he got done, but it seems like the idea is sound. I suppose that
              there are huge practical obstacles to be overcome, but with the expertise
              and innovation and creativity on this list, it just might be possible.

              Costas, is kitchen gas (natural gas) available in bottles (metallic
              containers),in Greece? Or is it available piped in, like in the states?
              What do trailers,(caravans) and motor homes use for cooking, heat,
              refrigeration? I know a lot of people like to use oil furnaces for melting
              metal.

              Brian in Brazil


              Em Mon, 04 May 2009 08:20:20 -0300, cvlac <cvlac0@...> escreveu:

              > Hi Eric
              > Thanks about all of this useful information.My problem here , in my
              > place, is that it is hard to find low cost propane to use it for this
              > purpose. I can only find small bottles used to weld copper tubes . And
              > they cost a lot of euros.And as Ben says it is always cheaper to
              > use coal as combustible.
              > Costas
              >
              > --- In multimachine@yahoogroups.com, "Eric Smith" <white_knight_411@...>
              > wrote:
              >>
              >> hehe, I AM a bit of a metallurgy expert.
              >> Propane is FULLY capable of melting iron.
              >> It's not as easy to achieve those temperatures, but it can be done.
              >>
              >> An easier, and some would say more dangerous, method is to use thermite
              >> welding technology to melt the iron. You'd have to do some research,
              >> but basically, you mix alu powder, and iron powder, light it off and
              >> run. when the smoke and flame stop, you've got a cooling mass of
              >> steel/iron.
              >>
              >> Cast iron(grey iron) melts around 1150 to 1200°C
              >> Naturally aspirated propane furnaces usually hit around 1200°C, but to
              >> actually cast iron, you need it much hotter than just "starting to
              >> melt". With a custom setup, and a large forced air system, I've seen
              >> propane temperatures closing in on 1600°C which is plenty hot.
              >>
              >> ONE large truck turbo should provide plenty of oomph for a small iron
              >> melting furnace. As for casting anvils though.... I've done it. Iron,
              >> and steel castings. If anyone asked me for another anvil, I can tell
              >> you, it would either be reconditioned, or I'd weld it together from
              >> heavy plate. MUCH simpler.
              >>
              >> My personal anvil is an old 500 pounder. the face was messed up, so I
              >> machined it(well, ground down actually), and resurfaced it using hard
              >> face surfacing mig wire.
              >>
              >> However you look at it, a "real" anvil is gonna be hard to make.
              >> Best to find what you can locally, and modify it. Provided you can get
              >> it legally, Railroad rail can make a serviceable anvil. Cut, shaped,
              >> and polished... they make a nice light, utility anvil.
              >>
              >> --- In multimachine@yahoogroups.com, "cvlac" <cvlac0@> wrote:
              >> >
              >> > Hi Ben
              >> > I'm not a metallurgist expert, but I think that you can't archive too
              >> hight temperatures with a propane burning furnace.Its Ok for alu,
              >> brass, but I do not think for iron and steel.Maybe you must select a
              >> better combustible (like diesel).
              >> > Costas
              >> >
              >> >
              >> > --- In multimachine@yahoogroups.com, "Benjamin Domingo Bof"
              >> <benjaminbof@> wrote:
              >> > >
              >> > > My idea is to build some multimachine in Brazil an becomes
              >> representant of this third world project. I can add welding electrodes,
              >> vise bench production now.
              >> > > But my drem is to make an iron and steel furnace by menas two
              >> series truck turbo blowers using propane gas bottle. Also to cast
              >> anvils using aluminothermy and perhaps graphite cricuibles because tyre
              >> repair shops uses graphite and is not expensive.
              >> > > Again; happy workers day for all members and moderator Pat Delany.
              >> > > Regards, Ben
              >> > >
              >> >
              >>
              >
              >



              --
              Brian R. Wood
              JH Manutencao
              Anapolis. Goias, Brazil
            • Pierre Coueffin
              Check this one out: http://www.foundry.ray-vin.com/fusion/fusionstory.htm He melts lead with a solar setup... Used a heliostat (array of flat mirrors,
              Message 6 of 18 , May 4, 2009
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                Check this one out:

                http://www.foundry.ray-vin.com/fusion/fusionstory.htm

                He melts lead with a solar setup... Used a heliostat (array of flat
                mirrors, individually aimed to hit the same spot) rather than a
                parabolic reflector, which is a lot cheaper to do.

                On Mon, May 4, 2009 at 5:21 AM, Brian R. Wood <brianrobertwood@...> wrote:
                > I heard somewhere that they use huge solar reflectors in India to smelt
                > steel, but I can't currently find anything on it so it may have been a
                > myth. There was a story on the internet of a guy using a big parabolic
                > mirror on an old pickup frame (for tracking purposes) to demonstrate the
                > power of the sun. (Solar Forge).
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