Craynerd builds Wilding's - Woodward's Gearless Clock

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raynerd:
Yep, I`ll have another go this evening after work. I know the reasonS why I went wrong so I`ll give it another bash. It was my stupidity. I spent most of the time setting up the cutter height which has been the issue in past wheel cutting attempts, that was good this time so I am learning.

Rob - in simple terms, the count wheel uses the swings of the pendulum to "count" the divisions of one complete 360 rotation in one minute. It is basically a ratchet wheel with 48 teeth. The pendulum does exactly 48 complete swings in one minute. The pendulum has a metal wire (pawl) attached to it and as the pendulum swings it gathers a new tooth each count. If you attached a "hand" to the count wheel, it would actually be a seconds hand rotating once in 60 seconds. However, it would look very odd on this clock, it would rotate 360 deg ever minute but would actually do 48 jumps/divisions rather than 60 jumps/divisions, i.e 60 seconds!! On this clock the seconds hand would actually go backwards as well as the pendulum count pawl pulls the seconds hand anticlockwise!

The nice thing about this clock is that I should be able to keep testing it at each stage. Once the count wheel and arbor is done, I can then test that it is "counting" the seconds...although it`ll soon run out of juice as the pendulum will be getting an inpulse. That being said, it should accurately time 1 minute, ideally a bit longer since the design of this clock only gives the pendulum an inpulse each minute.

Chris

raynerd:
I`ve spent a little while finishing this count wheel but managed it last night! The count wheel has these ratchet like teeth so that as the pendulum swings, the gathering pawl/wire slides up one of the slopes and drops behind a notch pulling the count wheel around one place.

I started with two rough cut pieces of 18g CZ120:

Made an arbor and chucked them both up:

Turned them down to 1.5" diameter:

I then made my profiling tool to cut the teeth, a 60 deg cutting tool but I needed a flat parallel to the mill bed when mounted:

I then unscrewed the chuck and mounted it on my rotary table on the mill. It managed to get out of true when I did this in my previous efforts so I set up a DTI just to check it was running OK - which it was this time! I must have knocked it last time, but my arbor was also longer in my other efforts which may not have held as well. Also, it sounds stupid, but I think there was some vibration last time and the chuck wasn`t tight on the rotary table that is why it didn`t cut properly.

I then centred the wheel - made sure by making a whitness mark, moving to the other side and checking it was at the same height - you can just make this out on the photo

I started cutting the teeth!!

Wheel teeth cutting complete and worked just fine!! :ddb:

I was then in two minds - remember I cut two teeth at once since it is 18g brass, the two together provided support for one another. I didn`t want to cross them out together as I risked spoiling them both if I failed. So I opted to remove one (as shown above) and remount the other on the chuck arbor and mount it under the rotary table. My dad then helped me with some nice maths so I could calculate how many degrees I needed to rotate the rotab and then lift the cutter for so many degrees and then back down etc to cross the wheel out

Then it was time to file it all square. I appreciate I could have got much more accuracy using the rotary table for all the crossing out but I decided to saw the little pieces out and file to size as described in the plans. This is the setup I`ve seen people use - a long wooden board, a groove cut and you sit on the board with the work nicely on platform infront of you ...worked very well

And after 20 minutes of rough filing I`ve got it coming to shape.

OK OK - it needs a lot more filing to make it look neat and quite a bit more work on burnishing the teeth but I`m nearly there.... :ddb:

Stilldrillin:
That looks great Chris! :bugeye:

Blummin well done! :clap: :clap: :thumbup:

David D

saw:
Good work :clap: :clap: :clap:

NickG:
Well done, looks great :clap:

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