Epicyclic Clock

[David NobleParticipant @davidnoble71990]

I've been looking around for a project and I'm thinking that the Strutt Epicyclic clock might be a bit of a challenge.

Does anyone have any advice or warnings

David

[David NobleParticipant @davidnoble71990]

[Michael GilliganParticipant @michaelgilligan61133]

I wish you every success, David

**LINK**

Epicyclic Train Strutt Clock

You might want to consider how you will cut all those internal teeth.

MichaelG.

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I guess it’s either plane them, or do this:

https://bwcmg.org/index.php/2020/10/06/an-epicyclic-clock-adventure/

 

 

Edited By Michael Gilligan on 01/11/2022 13:53:24

[KWILParticipant @kwil]

Micheal,

What an interesting reference. A lack of basic engineering experience also caused him problems, but he persevered.

[bernard towersParticipant @bernardtowers37738]

No mention of what cutter profile he used, I would have thought internal teeth had a completely different profile. No mention of them on Thorntons site.

[David NobleParticipant @davidnoble71990]

Thanks Michael,

I haven’t made a definite decision but it does look interesting. When I looked at the internal wheel teeth my first thought was to plane them but thank you for the link.

David

[Martin KyteParticipant @martinkyte99762]

Posted by bernard towers on 01/11/2022 15:03:57:

No mention of what cutter profile he used, I would have thought internal teeth had a completely different profile. No mention of them on Thorntons site.

at a guess you would probably get away with cycloidal tooth profile for internal and external.

regards Martin

[John HaineParticipant @johnhaine32865]

This is a movement I made which will go in the latest clock. The seconds arbor is driven by a stepper motor (back of the aluminium plate. The wheels are all cycloidal teeth about 1mm module cut with a 1mm end mill by profiling on the CNC. This could equally produce internal teeth. The profiles were generated by

http://hessmer.org/gears/CycloidalGearBuilder.html

and imported as dxf files into a CAM program to produce the g-code. The Hessmer program doesn't do internal teeth but Gearotic will but only for involute forms. There maybe something around that could do cycloidal internal profiles.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by bernard towers on 01/11/2022 15:03:57:

No mention of what cutter profile he used, I would have thought internal teeth had a completely different profile. No mention of them on Thorntons site.

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Strangely enough … The student write-up says [immediately following Fig.3]

“The cutting frame is held in an engineer’s vice, which in turn is fitted to a vertical slide. The frame needs to have the arms protruding so the Thornton cutter doesn’t hit it and can pass through the annulus wheel, to cut the full tooth depth. The cutter is attached to the brass rotor and acts like a fly cutter when it’s locked in place with a small pin. The rotor has ball bearings pressed in the sides and runs on two spigots that are threaded into the frame; power is provided by a secondary motor.”

So I am more than a little confused

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

O.K. __ I am pro-fused [as opposed to con-fused]

Please see page 14 of this periodical: **LINK**

[ Note: that’s page 16 of the PDF ]

https://www.awci.com/wp-content/uploads/ht/2005/2005-01-web.pdf

Read carefully and you will see that the student’s description does make sense.

MichaelG.

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Edit: __ ‘though it does seem rather extravagant when it’s a relatively simple job to make a fly-cutter.

Edited By Michael Gilligan on 01/11/2022 18:12:27

[John HaineParticipant @johnhaine32865]

The college probably had a full set of Thornton's cutters.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by John Haine on 01/11/2022 19:02:39:

The college probably had a full set of Thornton's cutters.

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… and probably Mr W R Smith had too

But that doesn’t stop me thinking that using one tooth of a cutter is rather extravagant.

MichaelG.

[John HaineParticipant @johnhaine32865]

Fascinating periodical Michael and great to see the Smith article. Thanks for the link.

[BazyleParticipant @bazyle]

Posted by Michael Gilligan on 01/11/2022 19:37:12:

Posted by John Haine on 01/11/2022 19:02:39:

The college probably had a full set of Thornton's cutters.

.

… and probably Mr W R Smith had too

But that doesn’t stop me thinking that using one tooth of a cutter is rather extravagant.

MichaelG.

You are allowed to use the same cutter in conventional mode for your next clock. They are not considered 'single use'.

[Michael GilliganParticipant @michaelgilligan61133]

Always supposing that you happen to already have the appropriate cutter sitting on the shelf

one slightly blunted tooth won’t matter much

… and anyway, Thornton’s only charge £35 +VAT to sharpen a cutter

.

Otherwise … I still consider it rather extravagant

Your opinion evidently differs, Bazyle

That’s fine

MichaelG.

[David NobleParticipant @davidnoble71990]

Gentlemen, please play nicely

David

I'm editing this to say thank you for the input. It has given me food for thought on how to cut the internal teeth.

Edited By David Noble on 01/11/2022 22:57:00

[Michael GilliganParticipant @michaelgilligan61133]

Posted by David Noble on 01/11/2022 22:54:46:

Gentlemen, please play nicely

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Don’t worry, David … I have nothing further to say on the matter.

MichaelG.

[Sam StonesParticipant @samstones42903]

How dare I even suggest lantern pins David?

Sam

[David NobleParticipant @davidnoble71990]

Posted by Sam Stones on 02/11/2022 00:35:45:

How dare I even suggest lantern pins David?

Sam

That's what I like about this forum, the broad spread of knowledge which can kick start the few brain cells I have left

Cheers Sam, hope you are well.

David

[Michael GilliganParticipant @michaelgilligan61133]

Dr Rainer Hessmer will assist:

**LINK**

Online Lantern Gear Builder

MichaelG.

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Edit: __ Yes, it does work with the relevant numbers,

but I can’t see any way to get the “pinion” inside the wheel

Edited By Michael Gilligan on 02/11/2022 09:00:29

[John HaineParticipant @johnhaine32865]

Wouldn't you use the pins for the internal teeth?

[David NobleParticipant @davidnoble71990]

Posted by Michael Gilligan on 02/11/2022 08:31:49:

Dr Rainer Hessmer will assist:

**LINK**

Online Lantern Gear Builder

MichaelG.

.

Edit: __ Yes, it does work with the relevant numbers,

but I can’t see any way to get the “pinion” inside the wheel

Edited By Michael Gilligan on 02/11/2022 09:00:29

Thank you Michael for the link.

I think that Sam was thinking of using the pins fixed to the face of the wheel rather then inside it but as you say, the pinion would not be inside the wheel.

David

[Michael GilliganParticipant @michaelgilligan61133]

Posted by David Noble on 02/11/2022 09:52:16:

Posted by Michael Gilligan on 02/11/2022 08:31:49:

Dr Rainer Hessmer will assist:

**LINK**

Online Lantern Gear Builder

MichaelG.

.

Edit: __ Yes, it does work with the relevant numbers,

but I can’t see any way to get the “pinion” inside the wheel

Edited By Michael Gilligan on 02/11/2022 09:00:29

Thank you Michael for the link.

I think that Sam was thinking of using the pins fixed to the face of the wheel rather then inside it but as you say, the pinion would not be inside the wheel.

David

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I’m sure he was, David … and equally sure that he will tell me, if am am wrong.

The other geometry, with radial pins [!], would be very difficult to make AND inefficient.

MichaelG.

Edited By Michael Gilligan on 02/11/2022 10:36:24

[Michael GilliganParticipant @michaelgilligan61133]

 

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using the pins fixed to the face of the wheel

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But presumably the teeth would need to be a different profile 

MichaelG.

Edited By Michael Gilligan on 02/11/2022 10:59:24

[David NobleParticipant @davidnoble71990]

I think that Sam was thinking of using the pins fixed to the face of the wheel rather then inside it but as you say, the pinion would not be inside the wheel.

David

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I’m sure he was, David … and equally sure that he will tell me, if am am wrong.

I've been stating the obvious again, sorry !

David

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