Propeller
casting. Start with cope, drag, pattern and pattern board.
Place
pattern board between cope and drag sections. Apply parting dust lightly
over pattern.
cover
pattern with fine riddle.
Completely
covering the pattern using the fine riddle will insure fine detail.
Fill
the rest of the drag using a coarse riddle. Flush to the top (see next
photo).
Ram
outside edges of mold using a ramming paddle. This prevents leaks during
pouring.
Ram
with peen side of rammer. North to south then east to west. Not real hard,
but evenly.
Then
fill the mold (without riddling), to about 2 inches over the top.
Then
ram with the butt side of rammer (harder ram).
Strike
off mold leaving a small amount of loose sand to cushion bottom board.
Place
board on drag section and flip the entire unit over.
Remove
cope section (empty) and pattern board from mold.
Propeller
is mostly buried. Sand must be cut down to parting line. The equator of the
Earth is a good example, separating the 2 halves of the mold at the "parting
line". 
Cut
down to the parting line and then smooth the sand with your spoon to insure
separation from the cope.
Mark
the location of your sprue by slightly pressing the cutter into the sand.
Place
cope section on mold. Apply parting dust to mold, this will keep cope and
drag separated.
Cover
the pattern using the fine riddle.
Fill
remainder of cope with the coarse riddle and tuck edges with paddle rammer
(same as drag).
Ram
mold east to west and then in a north to south pattern. Gentle but firm.
Same as drag.
Fill
cope 2 inches above top and ram with butt side of rammer. Then cope is
struck off and slicked smooth with a trowel.