Have now printed all of the parts for the new Pendulum clock.
I really like how you designed the way the small gear 2 fits onto the main ratchet. Very neat. I also like the way that you have made the option of using screws rather than a press/tight fit. I always found the tight fit to be tricky to get correct.
I have installed the electronics and have successfully had the pendulum swinging for the last 48 hour. The amplitude is quite large and will certainly look great. I have now started to try and put the thing together.
I have a few questions as I am having problems with measurements and getting the basics of the clock together.
Tonight, I wanted to get the centre gear cluster and the pendulum together to see how the thing fits, however, I am having some problems.
My first questions refers to your drawings and 75mm arbours. I have cut all of the arbours and I was under the impression that the 4 x 75mm long arbours/rods are for connecting the front legs to the main front dial. In your drawings you mention 75mm arbours but never mention the 95mm arbours which I have cut three of???
The 95mm main 3mm arbour seems to be too long?? Before shortening it, I thought that I would ask your opinion. If I use the 95mm arbour with the bearings, I cannot bring the front of the clock together square with the bottom frame. Even if I just place the 95mm arbour without the bearings it still seems too long.
I hope that my above comments are understandable and make sense. If not I can send some photos.
Many thanks in advance Steve and hope that these questions do not take too much of your time.
I am not sure yet how the clock runs as the batteries age. My clock has been running for around two months so far. The amplitude is still quite large, but the intended application is to swing a pendulum without any worry about amplitude.
This clock seems to need a bit more tinkering than the stepper motor desk clock. You may need to give a set of pawls to each recipient with a few instructions on setting them.
Have the clock going. I am using the longest active paw attached to the top of the pendulum with one of the smaller holders. The amplitude of the swing is quite large.
Am using the medium static paw.
Have tried to adjust it so that it can tolerate some voltage sag from the batteries as they age. Have no ide if the amplitude will change much as the batteries loose their charge.
Once again, thanks for many hours of fun.
Now to make a couple more clocks as they are becoming popular amongst my friends.
Interesting that the tall post is only 0.2mm short, yet the 95mm shaft does not fit. The CAD shows 97mm of clearance. There is no harm in trimming a few mm from the shafts. It will still be long enough to stay in the bearings.
The tall standoffs in the back frame are really just spacers. They are deliberately loose with a tighter fit at the bottom to align the arbor. Good point about the depth. I use aircraft drill bits which are about 6" long. I will add a segment in the assembly video on shaping the end of some music wire into a suitable "spoon" drill.
Not too sure if your interested but will let you know how I have gone.
I am using a Creality Ender 5 with an SKR Mini motherboard upgrade.
The internal distance between the front frame and the back frame at the base is 81.6mm which relates well with your measurement of 81.79. At the top of the frame where the back and front frames are held together by a screw was measured at 81.35mm so approximately square. The external measurement of the clock at the top is 98.1mm.
There was no way that I could fit a 95mm arbour at the top and be able to screw the top frames together. I took this down to about 92.5mm and this now fits together snuggly and the pendulum is still swinging well.
I also found that I had to gently tap the 95mm arbours that go into the back frame. The hole in the extensions from the frame had a very accurate dimension, however, the hole in the frame was slightly closed over and I struggled to find a long enough 1.5mm drill bit to drill out the hole in the frame. Probably a trap for young players.
I now have most of the gears fitted in the clock. Gear 3 is still printing. If work doesn't get in the way, I will have a go at the paws tomorrow night and should definitely have the thing going over the weekend.
Many thanks for a great design which provides many hours of fun.
Oops, there is a typo in the assembly manual. Thanks for finding it. The pages showing gears 3, 4, and 7 added to the clock will be updated to label the arbors as 95mm long. These changes occur on pages 30 and 32.
The 95mm pendulum arbor (highlighted in red) should fit inside the frame with a few mm of extra space. The space between the frames should be 81.8mm. This is determined by the height of the support column used to hold the frame together with the screw. If you already had the pendulum swinging for 48 hours, then it seems like the pendulum arbor is fitting properly. If the arbor is too long, it would rub against the frame and stall the pendulum.