Wooden Gear Clock

[Randy]

Interesting question; but I would "guess" that the answer is "no." Since several people have indicated that they have already completed working models of the clock and not mentioned this issue, I suspect the issue is a non-issue.; but it would be nice to hear from Marc just to be sure.

[Marc]

Clocks are built in degrees like 360 degrees in a circle. So the pendulum is addressed in degrees. The swing of the pendulum is 2-3 degrees to each side of center. This is determined by length of the flat part of the pallet that makes contact with the escape wheels teeth.
The pinions are glued to the wheels. They can be randomly glued on, but I try to balance them with the spokes of the wheels. I've received some emails from those who have completed this project. One in particular comes to mind and that is Steve Soich's clock. He did a great job and hopefully he will post some pictures on this forum.
cheers
Marc

[Randy]

Originally Posted by Marc

.....The swing of the pendulum is 2-3 degrees to each side of center.....

Using a little trigonometry applied to a 36" pendulum and it turns out that the swing of 3° works out to be 1.88" either side of center.

[okguzzirep]

i work in a shop making gears for winchs from 1in to 18in and up to 5 in thick
when i can get my wife (she works with wood not me ) i will get pd on it and will check what pin size that will work to check the gear

thanks richard

[ssoich]

Here is a picture of my rendition of Marc's 30 hour MLT-13. The clock has been running for about two weeks and is keeping good time.
Later when time permits I will post a few observations about the cutting and finishing of the gears and some other construction notes.
Any comments and criticisms are always welcome!

[Dragon]

my only comment on this is WOW. I am keeping all this information close by because one day I will build myself one.
Yours is awesome.
Diane

[Randy]

I got to the public library and made copies of the pattern to use for cutting the wood. Unfortunately they only had letter and legal size paper available so I had to shoot the front and back frames and the hour wheel in two parts and patch them together. Using original index marks on the pattern, I tried to match up the partial copies but they don't fit together perfectly. Did anyone else have this problem and if so how did you deal with it. Guess the simplest thing to do is visit a copy shop that has 11x17 paper??

[BobD]

Another option I've found is using the open source version of Excel (just google it). If you cut and paste the image into that cell, the program will tile it for you. That is, if you want to use the computer. You should have the half-size drawings as a PDF...cut and paste the images out of Acrobat Reader, and enlarge them in freeexcel to 200%

Thanks Gill, for providing this tip in the past!

Bob

[Jim8Mad]

It's really good to hear all of the success stories about this clock. I wish I had one to tell. I have tried just about everything I can think of to keep my clock running for more than two minutes with no luck. I have sanded/filed a few gear teeth and pinion leafs, polished every axle, checked every gear for rubbing or abnormal contact, triple checked to be sure my clock is hanging correctly on the wall, and I even added a little extra to the weight in case I got that wrong. Nothing is working for me.

Ok, here's the couple of problems I've had during the construction: a warped gear (replaced), oversized gear teeth (filed/sanded), a scored axle (replaced and polished). I couldn't find the 'thin walled' PVC pipe the plan called for, so I had to use thick walled (schedule 40). I compensated by doing a quick calculation of what the inside volume should be for the thin walled pipe and adjusted a little for the thick walled pipe. I figured that if my calculations were off then I would be just a little under weight which is why I added a medium sized socket to the weight to add just a tiny bit more weight. None of this made much of a difference.

What happens when I start my clock ticking is it will run fine for about 50 seconds, then the ecape wheel will begin to slow down and not do a full 'tick' without a little push from the pallets. I know this is a problem and did everything I could think of listed above and the only real improvement I saw was with the extra weight added. That managed to keep the escape wheel moving a bit better. Now I am noticing that the pendulum appears to be slowing down as it swings and eventually just doesn't move the pallets enought release the escape wheel and allow the clock to continue to run. It is still doing this every minute (about 50 seconds of smooth ticking followed by about 10 seconds of stubborn irritation). Also, I did not apply any shellac or varnish to any of the gears yet, so there isn't any in the teeth either. I saw something written earlier about 'polishing the teeth' (or something like that, I have to go back and read it all again). Does this really make a difference? Could that be what my problem is?

Please help me!! I need some advice of what to look for!! I do want to build another one of these as a gift for my Mom, but not until I can get this one running.

[Marc]

Jim, go back and buff out each tooth with your dremel pad. No buffing compound. Also do the pinions. The teeth and pinions may feel smooth to your touch but they are not. If looked at under a magnifying glass they are coarse. It's like walking in sand. The first few steps are okay, but eventually you will stop. Be sure to burnish the axles and clean out the axle holes in the frame. Diamantle the clock, and work with the GW first, then the 2nd etc. Make sure everything is turning freely. Be sure to buff the pallets where they make contact with the EW teeth. Buff the tips of the EW teeth. Also the pendulum spring must have a snug fit into the pendulum. If it is sloppy and loose the clock will stop.
If you are copying the pattern, find a copy shop that has a digital copier like a Toshibia, etc. They are most accurate. Be sure that the pattern is flat on the glass or it will be slightly distorted.
cheers
Marc