Progress of sorts

Discussion in 'Sand Casting' started by Chazza, Aug 5, 2020.

  1. Chazza

    Chazza Silver

    I had a problem last year with the sand falling out of a 1/8" thick steel moulding box; one of those irritating things where the mould works perfectly 10 times and then fails for 5.

    So I decided a cast aluminium box might have more rigidity and also if I placed a positive draft on the sides, it would be less likely to dump the sand. It worked well yesterday - yippee! I cast the handles/locators separately and bolted them to the sides. The top and bottom of the boxes were milled to make them sit nicely,

    Cheers Charlie
     

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  2. Melterskelter

    Melterskelter Gold Banner Member

    Charlie,

    Before you toss the steel boxes, maybe tack in some 1/8 x 1/2 steel bar "picture frames " 1/2 to 3/4" from the top and bottom edges of the boxes? That will stiffen them dramatically and prevent dropout too.

    The aluminum ones look great. The draft will really make shakeout easy when the time comes. But, what about inverting them? Maybe you use a board to hold the sand in. I could see routing in a groove near the top and bottom edge using a top guide bearing bit. That might help retain sand too. I routinely groove my wood flasks that way and routinely use internal angle or flat bar as suggested above as sand drop out is so frustrating.

    In one case, because the pattern left a very vulnerable poorly supported bar of sand along two sides of my flask, I had to put in a row of headed nails protruding into the sand 1.5 inches. Solved the dropout with never a failure on that pattern in that flask again. I've also welded in nails on another steel flask that takes the same pattern and had the same problem.

    Denis
     
  3. Chazza

    Chazza Silver

    All good ideas and practise Dennis.:)

    I won't chuck the steel ones as they work for smaller patterns.

    One of the immediate advantages of the aluminium ones is the stiffness of the walls, without anymore fooling around needed. The only precaution I take now, is to turn the cope over with a piece of melamine coated chipboard on the top, so that the sand can't drop out,

    Cheers Charlie
     

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