I spent a lot of my spare time this weekend making a few odds and ends that I had either overlooked or delayed until the
end. For example, there are couple of cleats for mounting the front crank plate that had to be cut, sealed, and stained to match
the other pieces.

Mars, Jupiter, Saturn Lantern gears

Then there was another piece for making the lantern gear. As to the latter, that needs some more detail.
The first three planets: Mercury, Venus, and Earth are all simply two gears. Mars and Jupiter both have simple gears too but they are connected together and to the lantern gear that drives Saturn. Why? Well, that’s what the plans call for but it’s easy enough to understand when you see it. As you can see from the photo, in order to get the gear ratio correct, it is necessary for the drive gear for Saturn to have only five teeth. Anything more would have required an increase in the diameter of this gear which would have required in increase in the shaft spacing which in turn would have made the entire thing bigger. Typically when the number of gear teeth get this low, one changes from toothed gears to a lantern gear like this. In this case, the pegs of the lantern gear are made from steel wire. To add stiffness and to connect it with the other drive gears, these pins go all the way through the Jupiter gear (which is pretty small itself, having only 12 teeth) and into the Mars gear. This all becomes one rigid assembly.

Advertisements