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clock winding ratchet

how do I build one, the one i need has 14 div. with id of 1.000. i know this is not like a gear like this https://www.ebay.com/itm/11mm-REPLAC...-/400676485932

So how is it done and what cutter I have never made one of these

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How bout this and a dividing head? You can get them in various angles. Could even use an inexpensive router bit. JR

dovetail cutter

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get just got that now how do i get 14 in to 360 = 25.7142857 for the div. I never have on this or a gear

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Originally Posted by Brett Hurt
get just got that now how do i get 14 in to 360 = 25.7142857 for the div. I never have on this or a gear
Can you plot that out on paper via the computer and use that as a guide with the dividing head? JR

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Originally Posted by JRouche
Can you plot that out on paper via the computer and use that as a guide with the dividing head? JR

Last edited by JRouche; 05-16-2018 at 09:26 PM.

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Do you even have a dividing head? If not, what?

14 divisions.

A spin index, which has 360 divisions will not come out even (360/14 = 25.71...). But a winding ratchet does not have to be very precise so you could round to the nearest degree and it would work. In fact you would be hard pressed to notice the differences. Here is a table you could follow. The worst error is 0.43 degree.

0
26
51
77
103
129
154
180
206
231
257
283
309
334
360

If you have an indexing head or rotary table that has any gear ratio that is even (1:40 or 1:90 are common ones), then you can use any hole circle that has any multiple of 7 holes: 7, 14, 21, 28, etc. If you can provide the details, I/we can advise on turns and holes per division.

If you have neither of the above, you can use a paper scale as suggested above. Any CAD program can compose and print a suitable scale. Again, for a winding ratchet, a lot of precision is not really needed.

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We are over - thinking this ! It's a simple ratchet not a cog wheel and in brass at that. How about a pair of dividers and a file.

Joe B

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Yep, in fact that is how some of the old clock/watch makers would have done it. Scratch a circle. Set the dividers with a good (or bad) guess. Step around that circle and observe the error. Make a correction and try again. Repeat until you can not see any further error.

Not super precise, but it will work.

Stop worrying about it and just do it.

Originally Posted by JoeCB
We are over - thinking this ! It's a simple ratchet not a cog wheel and in brass at that. How about a pair of dividers and a file.

Joe B

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Originally Posted by Paul Alciatore
Yep, in fact that is how some of the old clock/watch makers would have done it. Scratch a circle. Set the dividers with a good (or bad) guess. Step around that circle and observe the error. Make a correction and try again. Repeat until you can not see any further error.

Not super precise, but it will work.

Stop worrying about it and just do it.
That is actually a pretty precise way to map out a bolt circle.

I was gonna suggest that but it seemed like Brett wanted to use another method. JR

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