I thought you might be interested to see my recent SP5B build. I built older versions of SP5 in 2021 and 2023. The first SP5 worked reliably for a year or more before succumbing to stalling problems. The second one lasted less long, and both of them failed to survive a transatlantic move. I was interested to try the new SP5B design with its many improvements.
Here it is: https://www.youtube.com/watch?v=M9oTg79MRWA
This is the 8 day version. I might change it to one of the other versions later. I am also hoping to move to a house with a very deep stairwell, perfect for providing a very long weight drop!
I tried to reduce the friction as much as I could. As well as the ideas in the build manual, I used PTFE spray on the pallet and gear 1; carefully adjusted the set screw for gear 3 to avoid bending the arbor, as mentioned in a previous post; and adjusted the set screws for gears 3 and 4 so that ends of the arbors are clear of the bottom of the holes they fit into. Using a simple weight (no pulley), I had a mostly reliable run with 300 grams weight and I think I could have reduced it further. It is currently running with about 1200g, simply because I had a weight made up to this, and I intend to try to bring this down as well. (1200g is about 2.6lbs, so more than the 2lbs that Steve suggests).
A few more pictures:
I really like the way this one looks. The filaments are Flashforge burnt titanium, Eono co-extruded colors, and Amazon basic silk gold, plus a noname blue filament for the weight shell. The bearings are Xike ABEC-3 bearing: the best ones I found without spending much, by far.
Great looking clock. I really like the colors.
300g in the 8 day mode without a pulley makes the clock effectively a 4 day clock. The pendulum amplitude is probably just barely enough to keep the clock running. It wouldn't hurt to increase the weight slightly instead of trying to reduce it.
My SP5B clock has been running a long term test since it was designed around January of this year. It has the 20 day gear set using a 6.5 pound (2.95kg) weight. The bearings needed to be cleaned after 6 months. Possibly, there was some residual grease leftover. Also, I had one stoppage where either gear 3 or the collar slipped and pushed against the escapement. The escapement is so lightly loaded that very little friction can make the clock stop. I adjusted it and it is running great again, although possibly not as strong as when it was first built. I wonder if silk PLA changes over time. My longest running clock used an antique brass filament that seems to have a harder surface than silk PLA.