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

unable to superheat melt

Expand Messages
  • dean_schmidt
    Well, I melted and created my first ingots today! While I m happy my propane furnace was actually able to melt metal, I m a little concerned with it s
    Message 1 of 2 , Aug 31, 2003
    • 0 Attachment
      Well, I melted and created my first ingots today! While I'm happy my
      propane furnace was actually able to melt metal, I'm a little
      concerned with it's performance. From reading other posts the 20
      minutes it took for the aluminum to melt seems OK. I gave it an extra
      5 minutes before pouring however and the metal was freezing as I was
      pouring the third 1/2 pound ingot. I was pouring pretty quick too!

      I suspect either my furnace isn't insulated enough to heat much
      higher than melting temp or my burner isn't kicking out the BTU's.

      I'm using a stainless steel stock pot with 2 inches of commercial
      2800 degree refractory, a 2 inch drain, a 4 inch exhaust, and the
      burner is a modified Reil sidearm burner (naturally aspirated). 12
      psi seems to be the sweet spot as far as I can tell. Oh ya, I'm
      using a 4" diameter schedule 40 pipe crucible and on my second
      attempt I had most of the exhaust port covered with a plinth - same
      results.

      I'm going to use the wifes hair dryer for a forced air melt tomorrow
      to eliminate the burner from the equation. For those familiar with
      the modified sidearm burner, I couldn't find a 1.25" x 1.25" x 0.75"
      reducing tee so I had to use a 1" x 1" x 0.75" one. As a result I'm
      getting less airflow than the design calls for.

      If it turns out my burner isn't the problem, would coating the
      refractory with ITC-100 be enough to save this furnace?

      Thanks for any advice!


      Dean
    • edyn maniapoto
      ... Don t know if this helps? From what I can tell your Burner is operating correctly, or it wouldnt melt ally in the 20 min timeframe from cold.My monster
      Message 2 of 2 , Sep 1, 2003
      • 0 Attachment
        > While I'm happy my
        > propane furnace was actually able to melt metal, I'm
        > a little
        > concerned with it's performance. From reading other
        > posts the 20
        > minutes it took for the aluminum to melt seems OK.

        >Snip----Hey Dean
        Don t know if this helps?
        From what I can tell your Burner is operating
        correctly, or it wouldnt melt ally in the 20 min
        timeframe from cold.My monster Burner melts a 3/4
        full Steel Crucible(10mm Thick)of ally in about that
        time frame. I had a burner prob when I first got mine
        together and it wouldnt heat half the area of a 2mm
        thick cookie tin in half an hour,when I put a small
        chunk of ally in it,it took 40 mins before the ally
        just started warping. The problem was low fuel supply.

        > 5 minutes before pouring however and the metal was
        > freezing as I was
        > pouring the third 1/2 pound ingot. I was pouring
        > pretty quick too!

        Snip---How Full was the crucible? more ally charged
        in the crucible usually means longer melt time?
        I find that Smaller melts cool and solify faster,
        Bigger melts usually give more working time.

        > I suspect either my furnace isn't insulated enough
        > to heat much
        > higher than melting temp or my burner isn't kicking
        > out the BTU's.
        Snip----If your burners working correctly yor furnace
        doesnt need to be super effeciant, I can run my
        furnace with the lid off it and the burner will have
        the 10mm thick steel crucible up to a red heat in
        minutes.
        >
        > I'm using a stainless steel stock pot with 2 inches
        > of commercial
        > 2800 degree refractory
        > -----Snip My walls are approx 4"thick,The Temp
        rating of the refractory is 1650 deg/c. Usually higher
        temp rated refractorys are poorer heat insulaters,They
        are used to line blasting faces and are backed up with
        lower temp rated refactorys for insulating heat. your
        2" walls should be ok though!..as far as im concerned
        a furnace is just somwhere to put a crucible to blast
        with heat....he he

        > burner is a modified Reil sidearm burner (naturally
        > aspirated). 12
        > psi seems to be the sweet spot as far as I can tell.
        > Oh ya, I'm
        > using a 4" diameter schedule 40 pipe crucible and on
        > my second
        > attempt I had most of the exhaust port covered with
        > a plinth - same

        ---------Snip ..Your Base plinth should raise the
        Crucible into a position so it can recieve heat from
        the burner 1/3 from the bottom of its base.
        >
        > I'm going to use the wifes hair dryer for a forced
        > air melt tomorrow
        > to eliminate the burner from the equation. For
        > those familiar with
        > the modified sidearm burner, I couldn't find a 1.25"
        > x 1.25" x 0.75"
        > reducing tee so I had to use a 1" x 1" x 0.75" one.
        > As a result I'm
        > getting less airflow than the design calls for.

        Snip-----The Burner is burning at the tip of the tube
        right??.....NOT INSIDE THE TUBE!!!!!!, by the way from
        what I hear Blown burners are unreliable and are hard
        to tune - I think Ron Reil actually said that
        somewhere on his site.
        > If it turns out my burner isn't the problem, would
        > coating the
        > refractory with ITC-100 be enough to save this
        > furnace?
        Snip-----I think if anything you may just have to wait
        a little longer until the entire melt is heated to a
        point where its fully liqufied .....but hey thats just
        my opinion!
        Edyn.
        >
        >
        >
        > This list is for discussion of metal casting
        > and does not accept attachments. For off topic
        > discussion and to share photos and stuff: join
        > Sandcrabs by sending a blank message to:
        > sandcrabs-subscribe@yahoogroups.com
        > http://groups.yahoo.com/group/sandcrabs
        > For additional file and picture space you may upload
        > files of interest to:
        > http://groups.yahoo.com/group/castingproject
        > Please visit our sponsor: Budget Casting Supply
        > http://budgetcastingsupply.com/
        >
        > Files area and list services are at:
        > http://groups.yahoo.com/group/hobbicast
        >
        > To unsubscribe from this group, send an email to:
        > hobbicast-unsubscribe@yahoogroups.com
        >
        > For problems that cannot be otherwise solved contact
        > the list owner by email:
        > owly@...
        >
        >
        >
        > Your use of Yahoo! Groups is subject to
        > http://docs.yahoo.com/info/terms/
        >
        >

        http://search.yahoo.com.au - Yahoo! Search
        - Looking for more? Try the new Yahoo! Search
      Your message has been successfully submitted and would be delivered to recipients shortly.