I took a few moments to experiment with some of the ideas posted in this topic.
First of all, congratulations are in order to all the members of the bee kingdom for evolving their wax into such a durable product that to an extent confounded the best laid plans of mice and men to break it up into pieces.
First the failures (conducted on 1 lb wax blocks frozen overnight at about 0 degrees F):
(1) My idea to use a C-clamp (the wax block inside of a canvas tote bag) flopped; I simply could not apply enough torque to the clamp’s spindle (with my hand) with sufficient force to break the block,
(2) I then took the block and tried to squeeze it with a heavy duty cast iron vise; same problem.
But WE have a clear cut winner.
Congratulations are in order to Bee Happy for his/her idea (with some minor adaptations); I continued using a frozen block.
I used an electric drill and a TAPERED punch (the kind found in a punch and chisel set). I drilled 4 holes (eyeballed evenly spaced across an imaginary straight line; my beeswax is the common hexagon shaped one pound block); the drill bit I choose was slightly narrower, diameter wise, than the tip of the punch. To prevent making any more drill holes in my woodworking bench, I elevated the block onto two pieces of scrap wood, and left a gap between the blocks so that when the drill broke through the bottom of the wax block, the drill wouldn’t mar the table. Really easy to drill; the punch, hit with a steel hammer, broke each hole with one hit. The wasted wax (both on the drill bit and what shattered into very small shards when I hit it with the hammer) was negligible.
The only drawback with this method was that, IF required, it didn’t break up the wax block into very small pieces (which would, I guess, only be necessary IF you were going to weigh out a precise amount to put into your double boiler).