Making shot techniques

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What do you drill the holes with or do you buy the crucible pre drilled?
I always drilled them myself. I use a #2 bilge crucible and drilled 1 mm holes across the bottom. Probably 30 holes in total. Don't drill the holes too close or you will have a few oversized holes because the clay graphite between the holes collapses. Masonry bits always worked for me.
 
I'm surprised they ended up that spherical. I've always seen the best spherical shot come out from falling quite a distance before hitting the water. A close second was a fall into agitated cold water or alternatively, boiling water.
 
I hope these will help you in ball graining:
Silver graining is a bit different from gold graining.
Cold water is good for gold and also placing the drilled hole crucible close to the surface of water. 1 mm hole diameter is preferred.
For silver it’s better to use warm water about 40° C and place the drilled crucible not too close to water surface but about 20 cm above the water. 1.5 or 2 mm hole diameter is preferred. Drill holes in angled manner not vertical.
If the water got too hot some of the shot turned into spaghetti shapes.
I think the height of molten gold in the crucible is high that it turns to spaghetti shape. It means the pouring rate of molten gold from top crucible is very higher than the pouring rate of molten gold from holes. Or when the crucible is not hot enough the molten gold solidifies in the holes and then the height of the molten gold will rise up.
What do you drill the holes with or do you buy the crucible pre drilled?
If you use graphite crucible, the holes can be drilled with HSS drill bit. You shall not drill continuously, remove bit several times for cooling it, you can also use pressurized air for cooling the bit.
 


If you want the fancy spherical shot, use some kind of SS plate angled very slightly. Almost flat. Don't submerge it in the water. Obviously you'll want to put that plate deep enough in the bucket so no gold bounces out.
 

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