Shrinkage during drying and again during
firing should make this a close fit. Hole
has been widened and rounded on final
version.
Click any images to enlarge
Using a cross section of a bracket half,
I made a couple of preliminary
sketches, enlarging the shape slightly,
and then cut it out of a heavy plastic
extruder die.
Once the groove for the clamp has been impressed, I allow
these to dry until slightly stiff, and then cut them into sections.
I extrude long sections and lay them on a board over a wooden
dowel.
This is the part I will use to make the
clamps.
It's loaded into the extruder -- the thing I
referred to as a "giant playdoh fun factory"
;0)
I use a wood strip cut to size to make the impression where the
metal clamp will go. Each section will be three half-clamps.
Clamps dry for a few days on a wire rack, so they won't warp (even air
circulation above and beneath.) Then they are loaded into a kiln and
fired.
The extruder die will last indefinitely, and replacement parts can be made
to match even years later.