I use a 3/8" thick round mild steel disk with holes in it as a skimmer.
It does not heat up fast enough to melt when skimming.
You can slam it onto something hard to break off the slag, or use a ball peen hammer.
The side handle is not necessary; I am not sure why I thought I needed that.
There is a solid steel rod at the end of the square tube.
The square tube itself would melt off if it were welded to the skimmer plate.
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You can stir molten gray iron that is at pour temperature with a 1/2" steel rod, and if you stir for more than about 15 seconds, the end of the rod begins to melt off.
If you put that same 1/2" steel rod into the crucible by itself and try and melt it under the same conditions, it will not melt.
I think there is some chemical reaction taking place between the steel rod and the iron which causes it to melt.
Gray iron is generally poured in the 2,300 to 2,600 F range, per the Navy Foundry Manual.
Iron pyrometers are very expensive, and the tips don't last very long either.
Gray iron will start to give off sparkles flying into the air out the furnace lid opening, when you are at pour temperature.
You can also determine pour temperature of iron by how fluid it looks in the crucible, and by comparing the time it generally takes to bring iron to pour temperature in previous melts.
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