One of the ways we hope to improve this year is by sculpting subtractively rather than additively; instead of assembling a sculpture entirely out of individual parts that we have produced, we'll carve most of it out of a solid block. There will be parts, like gears and axles, that we will have to add, but the bulk of the piece will be carved, not assembled. Our hope is that this technique will allow us to create a sculpture faster, with improved aesthetic value, and with better overall use of ice. The technique does come with drawbacks, however, the principle one being the difficulty of boring holes for axles.
This problem was one of the major reasons we decided to use the additive method in the past. We thought that the best way to drill the fairly large (3.5 inches usually) holes for axles would be to use a drill press on individual frame segments and then assemble those pieces together. The drill press does a good job of boring very straight holes, even with homemade bits, perfectly perpendicular to a slab of ice. Then it is simply a matter of aligning those slabs correctly when assembling the frame. Unfortunately it has turned out to be slower and more difficult than we originally anticipated to execute this process. In order for the frame pieces to be assembled with perfect alignment, many pieces must be produced, each piece must be very precisely shaped (more precisely than can be done with a chainsaw), and a lot of watergluing must be done.
Turning to the subtractive method brings back the problem we at first sought to avoid: How do you bore 3.5 inch holes through two feet (or even more) of solid ice while keeping the hole perfectly straight, level, and parallel to an adjacent hole? Some weeks back, I was discussing the problem with Dan, and he had an intriguing suggestion: lasers! By mounting one or more lasers on a hand drill and marking a target on the far side of the block of ice, it should be possible to keep the drill precisely on the correct path by aiming the lasers at the target. I loved the idea because it is simple and takes advantage of the transparency of the medium. It is certainly worth trying as it is much easier than constructing some sort of deep-boring, horizontal drill press.
This is the technique that Lars and I intend to use to bore axle holes in the frame of our sculpture this year. Fortunately, Lars was smart enough to point out that the method can only be used at the precise angle perpendicular, or normal, to the ice surface where the drilling begins; otherwise we would have to account for refraction of the laser beam when placing the target on the far side of the ice!