It's time again to take a break from the Six Planet Genesis that I am currently working on to spend some time in the workshop teaching with my nephew as we work on our new small six planet orrery design. I really need to come up with a name for this new model. It is based on early 18th century orrery so perhaps I should start my search for a title their. I quite like Cassini, whom discovered four satellites of Saturn as well as many other astronomical discoveries based around the planets and moons featured on this orrery. In-fact as I write this I have decided to dedicate this orrery to the great astronomer Giovanni Domenico Cassini.
A cool Saturday was spent in the workshop cutting gear teeth into the blanks we turned the previous weekend. That's 2,308 teeth cut and Harry done really well not making one mistake, it's sometimes hard to believe that he is only 13. Whilst Harry cut teeth I turned the smaller gears that we did not manage to get round to the previous week.
The gear train for this orrery needs to be compact due to the base only being roughly 7" in diameter and the need to store the entire gear train within the base. We are using 40, 36, and 32 dp gears to achieve this using only 2 fixed pitches. I am proud to say that the error for the movements on this orrery is less than 0.01%.
Next weekend we begin assembly of the gear train. This will involve making the steel plates that house the gear train, cutting the planet tubes, and some turning. I will be back with an update.
It has been a month since my nephew Harry and I began working on the small batch of six planet orreries. We originally thought we would be spending a day a week making these but yesterday was only our second day on project. I have been carried away working on a Six Planet Genesis which is taking up most of my time however I have decided to set aside more time for this going forward.
We have made a start with the gears. I began with making the tooling we would need in-order to speed up the gear making process. I turned a mandrill from steel that will hold several gear blanks for turning and teeth cutting.
Harry roughly cut the blanks from brass bar and then bored the centres. He then handed them over to me to turn to the correct diameter on the lathe.
We made enough gear blanks for four orreries, the pinion gears are yet to be turned but I can do this next week whilst Harry cuts the teeth. I am very happy with his work yesterday as it was stiflingly hot in the workshop and the sunshine was tempting us to down our tools and relax. We can enjoy a well earned rest today, it is Sunday after all.
I will update you on the project next weekend.
One busy orrery makers attempt at giving a peak behind the curtain of an irregular job in somewhat regular intervals.