Thread: My Wooden geared clock

Hi all I managed to do some simple calculations. 8.35pm-7.05am The weights traveled 360mm so I expect to get 60 hrs or 2.5 days1 Not too bad. So If I wind it at 7pm Monday night I willl have to rewind it 7am Wed morning. My 13y/o daughter helped me with these calcs!

Dean

Here in Coogee and elsewhere in Sydney humidity has struck! The 27T attached to the timing wheel has been jamming Here are some pics of the replacement FINAL gear I made this week. I reduced the tooth height by .65mm and made the valley of the tooth .65 deeper as well. The first pic is the reduced diameter gear on top with the original one on bottom. You can just make out the wider crown on the top gear compared to the original one. I hope its not too clunky!. The second pic is the old pair which had both 4 & 5 spoke gears. The third pic 3 shows the final configuration that have both 5 spoke gears.I like the look of these!

cheers

Dean.

I was expecting that after I re-assembled my clock that the tick would tock but it did not. The amount that I undercut was not sufficient so out came the humble warding file! I waited patiently for the high spots to come around on the 27 Tooth and its mating gear and filed them away. The clock has ran overnight; albeit a little fast but the fine tuning can come later. I have 2 circuits that run my clock; 1 you can adjust the duration of the pulse and the second you cannot adjust. It measures and tries to regulate the bob so that it is exactly a second in length. The red power wire broke some time ago and I could not get this circuit to work again for some months. This week I decided to re-solder the wire and now by some miracle it is now working. I will now be adjusting the first circuit and the lower mini bob to get the time right again.
Along with this I am re-making the coil housing to make the adjustment precise; for now both the coils position is not adjustable and is held on with sticky tape!. More pics soon,.............

Dean.

Hi all some progress on my coil housing. This will be mounted on the wall under the pendulum rod.Hope to have it completed this week.



Dean

Merry Christmas to all! The final installment for some time until we move house! That will put a dent in any clock-making endeavors! Here is an early prototype of the coil housing. Most of the design elements will carry on until the next edition; i love the ability to adjust the coils in the z and y direction. I have learned to use non-ferrous fastnners only!. Humidity is still an issue but hopefully the move away from the beach will sort that out or perhaps it will make in worse?


cheers to all

Dean.

I wondered why you elected to use only 4 spokes, could not improved stability have been achieved with say 6 (maybe even 8) spokes of reduced size?
You don't say what method you used to limit the ultimate effects of annual air moisture variations. A wax finish is sometimes claimed to work, well but I would always opt for several coats of polyurethane. I guess you would want to store all parts together in some form of controlled atmosphere before moisture proofing?

The rule of thumb is you do not put any finish on the gear teeth as this creates friction so there is always a moisture Ingres point.
If more or less spokes would help is a good question, Don't know.

Russell

Hi peter,
"You don't say what method you used to limit the ultimate effects of annual air moisture variations"..I dont have a method yet. I would love to find one. I have an idea of freezing the timber to effect the cell wall to slow down the amount of moisture absorbed until EMC is achieved. This idea is from the attached article. I am looking into this as soon as I have moved house! If you have any secret moisture proofing concepts please feel free to share. As Russell has said any coating affects the friction but netherless I have used some organ oil to try to seal the gear. It does tend to turn chalky.

The initial reason why I used 4 spokes is that the plans only had 4 spokes and i didnt know what the hell I was doing. Now after a couple of years I have some idea. I noticed that there was a high spot between each spoke. I reasoned if I had more spokes it would reduce the area that was unsupported and prone to bulging between each spoke particularly during high humidity events. So now I recommend 6 spokes. My isoloc concept has helped well during low humidity but not so much when the humidity peaks.


Dean.

Hi finally settled in and have relocated my clock downstairs where it is cooler. One of the 60t is still an issue when the humidity is high. I have just finished designing a 7 spoke one tha has the diameter by 1.5mm as well as the deepening the each tooth by the same amount. Just to see what happened I will try freezing the other 6 spoke gear to see what happened. More soon.image.jpg

Hi all. Today i have started my experiments with freezing timber to see if I can overcome the effects of warping. I got the idea from an article (which is attached to post 324. It suggested that freezing would be beneficial and would help reduce deformation and there "is, in fact, a certain reordering of the distribution of water and the typically wood resins' I hope this equates to less warp after the teeth are cut. To begn my experiemnts I have frozen a 6oTooth isoloc for 3 days at -15. I will then test to see if the gear is less warped that before it entered this frozen state.Dean.

I took the gear out of the freezer today. It does seem a little straighter but I am not convinced. I have decided to pre-freeze the pieces for my next gear, let them thaw out, cut them, fit them together to form the blank and machine as normal. This is I hope my final gear and have decided to make a seven spoke one.


cheers

Dean

Hi all
the fridge has been full of timber this week.The freezing has made a difference but how much will be known at the end of next week.
Dean.

Hi all
Another busy week sees the end of the making of my seven spoke gear. I will be re-assembling the clock tomorrow and will see how it runs. With a gear removed and the clock gears free to turn I discovered a 20Tooth gear that was jambing as well! This was the exact same gear that I had reduced the overall diametrer earlier. So I will reduce the diameter again by 1mm and re-assemble again and see how it runs.I will not give up till this clock can tell the time on its own!






cheers

Dean.

You must be getting close Dean.
The new gears look good