BruceB
11-02-2006, 02:35 AM
Gentlemen;
The Pro-Melt furnace has an adjustment for rate of flow from the spout. It's a simple socket-head limiting screw mounted vertically above the arm which the operator lifts to open the bottom spout.
I'm a firm believer in keeping the pot almost full, both to aid in keeping a constant flow pressure, and to speed the melting of pre-heated ingots. This isn't likely all that important when using an air gap between the furnace spout and the mould top, but I suspect it may well make a difference when casting with the sprue plate hard against the spout. In the latter case, the head of pressure from the furnace does indeed have an effect on the happenings inside the cavity....or so I think. Some of my moulds make better boolits when they're pressed against the spout for filling, so I believe this may have some relevance.
The pot holds around 22 pounds of alloy, and I always add a 3-pound ingot whenever there's room below the rim. Even with the limited variation of 3 pounds plus-or-minus in the pot, there is a CLEAR DIFFERENCE in how the metal flows, between plumb-full and minus-three pounds.
As a result, I have permanently installed an Allen wrench in the head of the flow-adjusting screw. By doing this, I have an excellent visual gauge as to where the screw is positioned at any time (since it never takes a full turn for required adjustment) and also I don't have to look for the gol-danged key under everything on the bench or floor when I want to tweak the flow rate.
As little as 1/8 turn on the adjustment screw makes a perceptible difference (meaning, a difference I can see or feel), and I find it a useful convenience. The lock-nut on the screw is just backed 'way off to avoid its interfering with easy movement of the screw.
If one fires up the pot and then casts the entire contents without refilling, the flow adjustment could be much more critical as the pressure head decreases. I don't cast that way, so I can't really say.
I was casting a mess of 311466 Loverins yesterday when I got to thinking about this. Been doing it for ages, but never mentioned it here on the Board. It's a minor factor, for sure, but it affects how my operation makes boolits and I figgered I might as well post it.
The Pro-Melt furnace has an adjustment for rate of flow from the spout. It's a simple socket-head limiting screw mounted vertically above the arm which the operator lifts to open the bottom spout.
I'm a firm believer in keeping the pot almost full, both to aid in keeping a constant flow pressure, and to speed the melting of pre-heated ingots. This isn't likely all that important when using an air gap between the furnace spout and the mould top, but I suspect it may well make a difference when casting with the sprue plate hard against the spout. In the latter case, the head of pressure from the furnace does indeed have an effect on the happenings inside the cavity....or so I think. Some of my moulds make better boolits when they're pressed against the spout for filling, so I believe this may have some relevance.
The pot holds around 22 pounds of alloy, and I always add a 3-pound ingot whenever there's room below the rim. Even with the limited variation of 3 pounds plus-or-minus in the pot, there is a CLEAR DIFFERENCE in how the metal flows, between plumb-full and minus-three pounds.
As a result, I have permanently installed an Allen wrench in the head of the flow-adjusting screw. By doing this, I have an excellent visual gauge as to where the screw is positioned at any time (since it never takes a full turn for required adjustment) and also I don't have to look for the gol-danged key under everything on the bench or floor when I want to tweak the flow rate.
As little as 1/8 turn on the adjustment screw makes a perceptible difference (meaning, a difference I can see or feel), and I find it a useful convenience. The lock-nut on the screw is just backed 'way off to avoid its interfering with easy movement of the screw.
If one fires up the pot and then casts the entire contents without refilling, the flow adjustment could be much more critical as the pressure head decreases. I don't cast that way, so I can't really say.
I was casting a mess of 311466 Loverins yesterday when I got to thinking about this. Been doing it for ages, but never mentioned it here on the Board. It's a minor factor, for sure, but it affects how my operation makes boolits and I figgered I might as well post it.