Jump to content


New Member
  • Content Count

  • Joined

  • Last visited

  • Feedback


Everything posted by bobhare

  1. This shows the Knife edge bearing and the lower impulse face narrower than the upper. View of escapement and pendulum arrangement. This shows the knife edge in it's fitting. A point i forgot to mention earlier. It seems the pendulem is not getting enough energy from the escapemant so i increased the weight driving the wheel but this only seems to have the effect of making the movement clunky. The wheel rotaes faster and the pallets don't have time for the locking faces to enter properly.
  2. I'm building a clock with woden gears and have set up the escapemant with which I'm having some problems. The clock is pendulum driven and the mechanism is driven through a chain wheel. I have been testing the escapemant without the gear assembly to eliminate any issues from that. I've used the design provided in Brittens Watch and Clock Handbook for the Dead beat escapement with 30 teeth on the wheel. The pallet is solid and made from steel whilst the wheel is made from aircraft grade aluminium. (I tried making it from brass but the teeth profiles were poor). They are both CNC machined a
  3. Update. I've now made the following changes and things have significantly improved; more later. I remade all the gears using cycloidal tooth profiles. There is much more freedom in them and hence any meshing friction is minimised. I fixed all the gears on their own pinions and placed their bearings in the plates. I'm still using PTFE bearings but as one of them is threaded I can adjust the end float. I have not polished or lubricated the teeth I had the pinion for the second hand far too long and it projected from the front plate by about 100mm. As it was made from
  4. I think that i understand your reasoning. Gear 3 currently runs on the shaft to which pinion 1 is fixed and whilst they both run in the same direction they run at different speeds. I can fix the shaft on which they currently run and only gear 3 will run on this shaft. I will then have to put pinion 1, fixed to the escape wheel,running on a new seperate shaft. Is this correct? Driving the gear box low to high was a concern early in the design but i could see no way around this; hence making the plastic assembly. I used involute gears because i thought they would be the best
  5. Thanks for your reply;much appreciated. As you have probably realised i know very little about clocks but suddenly decided to make one. Some images of the clock here: https://www.flickr.com/photos/188874329@N06/? The minute hand is on gear4 and there are two other gears between this and pinion 1, the second hand. Unfortunately the second had rotates anticlockwise so there is another gear to reverse the rotation. Between gear4 and the winding drum there are a further two gears which drive wheel 7 which is locked to the winding gear. There are then another set of gears to drive the hou
  6. There are 18 gear wheels; being 7 pinion/wheel combinations and four separate pinions. The shafts rotate in plain bearings with the steel shafts running in PTFE plain bearings. After using 1000 grit paper on the shafts i further polished them with brasso, a mild abbrasive used for polishing metal. Could you explain what you mean by, "Their size is very important"? I'll upload some photos when i have mastered the technology. Thanks.
  7. I've designed and built a clock with wooden gears but without applying excessive torque on the chain wheel the gear train will not run. A little bit of background. I wanted the clock to have a pendulum, have a second finger and require winding every eight days. The escapement wheel has 30 teeth and is on the shaft for the second hand. An arrangement of gears with a ratio of 1:60 drives the minute hand and a pair of gears with a ratio of 1:12 drives th hour hand. In order to achieve the 8 days between winds a further set of gears with a ratio of about 1:24 drives the hour hand. This m
  • Create New...