Carving a pyramid in hard carving wax is not difficult, but involves
precision with your layout and carving technique. Your first "test"
of your technique is carving a perfect cube out of wax, with smooth
sides. You’ll need a broad, coarse file, which won’t load easily with
wax, but will still leave a relatively smooth surface on the wax. A
machinist’s square will be required, to check for absolute squareness
on all sides, and an accurate calipers (digital recommended) to
measure each side of the cube. Once you’ve managed to carve a perfect
cube, with smooth sides, you have graduated to "Advanced Wax Carver"
status, as there are not many people who can accomplish such a feat
by hand processes. ( You can DO this!) Once you have the perfect wax
cube in hand, you can take your dividers and draft two faint,
accurate lines through the top surface of the cube, splitting the top
into 4 equal quarters. You should have a perfect “bulls eye” cross in
the center. That cross’s center represents the very tip of your
Carving the two opposite sides is the easiest, as you have the
guide-line on the top to carve to, to keep flat sides on your
pyramid. The last two sides are trickiest, to keep your planes even
with the bottom of the pyramid. Don’t file over your guide-lines, and
keep your sides flat, and you will carve a perfect pyramid.
I would recommend hollowing out that pyramid from the bottom,
leaving approx. 1 mm wall thickness for casting, or you will have one
monsterously heavy casting, probably with porosity.
Molding a solid pyramid will probably mean “sucked-in” sides due to
shrinkage of the liquid wax in the mold.