First and foremost I want to say a huge thank you to everyone for coming out to the construction meeting over the past 2 weeks to work out the ‘boggan design; it’s really paid off as I think we’re really close to a working construction design.
A short-and-sweet update for everyone…
The Structure team has come up with the concept of a tobboggan that runs on 2 concrete ski’s with a small space between them. The superstructure is going to be shaped like a coffin and will be connected to the skis through a c-channel welded-bolt connection. This connection is unique in that it will allow us to remove ski’s from the tobboggan if need be (in case one ski cracks or breaks). The superstructure will likely be made of aluminum, with steel load bearing members if need be, and have fibreglass sheeting on the outside to simulate the look of a real coffin straight from the grave.
The Mechanical team developed the ‘boggan’s steering and braking system. The steering system concept is similar to that which was used in 2009, with a single concrete ski attached to a drive-shaft that can be controlled by the person at the front of the tobboggan. Right now the team is playing with different steering designs and configurations in order to maximize the safety of the driver and still allow for the greatest control of the ‘boggan. The braking system consists of a multiple short, hollow metal tubes welded side to side to form a drop-plate. This drop plate will be attached to a metal rod that is put under torque by a pre-tensioned spring attached to the superstructure. This drop-plate/spring apparatus will trigger when a pin is pulled from a rod within tube construction and; much the same as a mouse-trap would function, the brake will “fire” downward into the snow. In order to allow for safety, a manual handle will be attached to the drop-plate, in order to allow a ‘boggan rider to add more force to the downward motion as well as pull the brake up off the snow when required. If you are confused by this… rest assured, concept drawings will be posted in the near future.
Lastly, the Concrete team is really stepping outside the box this year, proposing to construct the concrete skis as prestressed concrete. In order to do this, the team is going to prestress guitar/piano/bass strings within a concrete and fly ash mixture. The team hopes that the prestressed concrete will give the slab strength in both tension and compression. This is just the first of their mix designs as the team will be pushing forward testing a number of different mixes and reinforcing methods.
Next week the design concept of the sled will be refined into a working construction model. This will allow the team to begin drafting construction drawings, pounding through calculations, as well as begin acquiring construction materials. Stay tuned as we construct the Night of the Living Sled.