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Re: Stupid Question Need Help About Aluminum Actual Melting Process.

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  • gregsfoundry
    ... This is true aluminium melts at such a low temperature that if it ends up on your skin when it is molten it will stick and you will need to tear it off. so
    Message 1 of 51 , Apr 29, 2009
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      --- In hobbicast@yahoogroups.com, <jbrennan3@...> wrote:
      >
      > you are trying to run before you can crawl let alone walk.
      >
      > Goggle: home casting aluminum
      >
      > If you have problems after you work your way through what you find .. ask specific questions.
      >
      > If you don't do this--- you will get hurt.
      >
      This is true
      aluminium melts at such a low temperature that if it ends up on your skin when it is molten it will stick and you will need to tear it off. so protective clothes are a must
      Anything that you pour tne metal into must have no volatiles (ie wax etc)must be dry (no moisture) and is best if warm or hot.
      any mold that has dead ends where air can get trapped will blowback big time when you pour the aluminium in.
      When I was studying one of my lecturers who had been casting for many years casually threw a bronze ingot into an induction furnace when halfway through melting ....it must have had a drop of moisture on it because the next thing that happened was it spat out molten bronze which ended up in said lecturers eye..so never add cold wet metal to the molten stuff. Cant think of any other tips but really if you just be over cautious and keep asking questions no matter how basic it is a joy to work in these materials and it can be done relatively safely.
      Greg.
      p.s. keep asking questions
    • Stone Tool
      Hasn t this gone on long enough?? The truth is that the wavelength of light radiated from heated metal is predictable based on the temperature of that
      Message 51 of 51 , May 3 8:40 AM
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        Hasn't this gone on long enough?? The truth is that the wavelength of
        light radiated from heated metal is predictable based on the temperature
        of that metal...... something metal casters and blacksmiths have known
        for centuries.

        David Patterson wrote:
        > since your looking into a furnace you can't judge the color of the aluminum in the melt. as you said aluminum is highly reflective. the color you see is a reflection. in visible lightwhen you pour the melt you will not see that color. but it seem we've reached an impass so this was my last word no on to casting.
        > Dave Patterson
        >
        > odd_kins@...
        >
        > http://home.comcast.net/~oddkins/foundry_home.html
        >
        >
        > --- On Sat, 5/2/09, Jeshua Lacock <jeshua@...> wrote:
        >
        >> From: Jeshua Lacock <jeshua@...>
        >> Subject: Re: [hobbicast] Re: Stupid Question ///steel crucible
        >> To: hobbicast@yahoogroups.com
        >> Date: Saturday, May 2, 2009, 4:46 PM
        >>
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        >> On May 2, 2009, at 8:04 AM, David Patterson wrote:
        >>
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        >>> I don't have a probem with Planck's Law, but
        >> for someone to say they
        >>
        >>> can tell the tempereture of aluminum within 50 degrees
        >> just by
        >>
        >>> looking at it, I know a lot of foundries that would
        >> like your
        >>
        >>> expertise.
        >>
        >>
        >> The eye can discern 7 to 8 million different colors. To me
        >> the
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        >> difference between bright cherry red and salmon or salmon
        >> and dark
        >>
        >> orange is absolutely obvious. With a bit of experience, if
        >> one pays
        >>
        >> attention, you can pretty easily tell half way between
        >> bright cherry
        >>
        >> red and salmon which is about 50 degrees.
        >>
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        >> I claim no miraculous powers.
        >>
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        >>
        >>> http://www.goinfrar
        >> ed.com/media/ 2005-020% 20Mollmann. pdf
        >>
        >>> this web site, tor those reading this, might help
        >> explain Planck's
        >>
        >>> Law. there is also a picture of a crucible of molten
        >>
        >>> aluminum.... .looks silver to me, but that could just
        >> be my eyes.
        >>
        >>> http://www.youtube.
        >> com/watch? v=565bFybx0zk& feature=related
        >>
        >>> and this video shows clearly the visible color of
        >> aluminum when
        >>
        >>> poured in lighted conditions when is when the pour
        >> should
        >>
        >>> happen....don' t turn off the lights when
        >> pouring.
        >>
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        >> I have already explained the reason why the color may not
        >> be as
        >>
        >> obvious when the molten aluminum is in bright sunlight.
        >>
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        >> The reason is because aluminum is highly reflective, so you
        >> are seeing
        >>
        >> the ambient light strongly reflected. As I also previously
        >> stated,
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        >> aluminum begins to melt right when a glow is just hardly
        >> visible. Try
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        >> reading up on black body radiation - basically the darker
        >> the
        >>
        >> material, the more obvious the glow color will be.
        >>
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        >> Although, the color emitted is the same color, it can just
        >> be quite
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        >> faint. In other words, you may not notice unless you look
        >> for it.
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        >> Look at the link you sent in a earlier email, this
        >> person's crucible
        >>
        >> looks just about the same color as my crucible that I
        >> posted, and yes
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        >> he is pouring aluminum:
        >>
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        >> http://www.foundry1
        >> 01.com/1. htm
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        >> Sincerely,
        >>
        >>
        >>
        >> Jeshua Lacock, Owner
        >>
        >> <http://OpenOSX. com>
        >>
        >> phone: 877.240.1364
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