Any clockmakers that can help me find a gear?

My mother in law gave me this kaleidoscope like thing years ago. Might be hand made, the glass appears to be painted showing brushstrokes and the four mounting screws holding it together aren’t quite symetrical so face only fits one way.

It is missing a gear to turn the two lenses. It appears to be 14 tpi, about . 1875 diameter.

Looking for local clockmakers that might have parts I could make work. Or an online source recommendation.

OK, this isn’t as good as a personal recommendation, but it might help:

#2 (Antique and Modern Clock Repair/Carrollton) says he repairs/replaces missing gears.

(EDIT: I sorta know a guy, but don’t know the name of his shop, and while searching for the name of his shop I found the link above).

Or you can at least make one yourself.

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Involute - Haven’t seen / heard the term since Walter’s gear making class.
Went down the involute curve math rabbit hole and encountered some rather intriguing trig math.

I’m in Coppell so Carrollton would be convenient. Would definitely try to buy something vs make a gear but thanks for the idea.

Many years ago I used the formulas in the machinery’s handbook to generate the toolpath to cut chain sprockets, found a mistake where two arc’s were not tangent, then found a newer copy of the handbook and that had corrected formulas.

Links posted by other Makers in the past.

ahh, gears are easy. They just take time. We have the indexing head, we just need to get the gear cutters & collet/tool holder. There is nothing more enjoyable for someone to say that it’s too complicated than to turn around and do it. You could design it in Fusion, then 3D print it to check your design. I did that for the offset head for the mill port.

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Man this is a tough crowd, ask a simple question on where to buy something and I get more answers on how to make it. You guys all seem to be shaming me into taking this on. I’m behind on so many other home projects that I first need to see if I can buy a gear for less than it would cost to buy the cutters needed to make a gear.

And I’m recovering from a mountain bike crash, broke some ribs, scapula, clavicle 3 weeks ago. Had surgery 2 weeks ago. Just got released from driving ban by my wife yesterday. You can see the fractured scapula in lower center of the photo. I’m cleaning my shop and trying to work on little things that don’t require a right arm for the next few weeks. Actually feeling pretty good considering what I broke.

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Sorry Randy, that wasn’t the intent. By 3D printing, you could check your work and save you some frustration of getting the wrong pitch or dimensions.

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You paid someone to make that simple plate? You could have made that with even one arm on the Bridgeport from a piece of scrap SS! :wink:

In all seriousness, no shaming was intended by anyone, but it does look likely to be a hard to find part not something OTS
Good luck!

Yes, it is a tough crowd! @TBJK Tim probably would have made his kids fabricate one for him and install it himself.

Here’s a source that may help.
https://www.sdp-si.com/products/Gears/Index.php

image
image

Now we know what makes Tim tick…

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I think the piece of Titanium in my shoulder was around $10K plus $15K to install it and I have thought how can that be possible for what looks like a pretty simple part. I definitely thought if I had planned ahead I could have made it myself.

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Sorry to do this, but every time I scroll past that x-ray, this is what catches my eye…

Is this some kind of joke?
Oh,
image

Again, I apologize. I’m quite certain for the recipient, it is no joke, which makes me wonder why they put that on the X-ray…

RTRR stands for Real-Time Radiography/Radioscopy meaning that it is a computer generated image rather than an X-Ray film image. My Dentist uses the same technology.

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Figured as much.
At least the OP is in good company, then, as pretty much everyone gets a hearty harteeharhar on their xray…
:+1:

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It’s also to signify which direction the X-ray is taken from. If the R was backwards it could mean the picture was taken back to front instead of front to back or it could also mean left vs right shoulder.

The cost of the part has a lot of other factors built in besides raw metal and machining time:

  • Carrying cost (bone plates like this are relatively low volume and most hospitals keep at least one set of them on the shelf)

  • certifications. (The material has to meet tons of stringent requirements to be implantable grade, fda clearances, ongoing material testing, fatigue testing, etc.)

  • preparation ( medical supplies touch a lot of hands and go through a ton of processes before they ever get implanted. Testing, validation, hand assembly, hand inventory, Transport, sterilization, monthly / bi monthly inventory, resterilization, etc)

And lots more stuff, but those are the big 3 off the top of my head right now.

Implantable technologies are most akin to aerospace in engineering, low volume high cost.

Fun engineering thing about your particular plate and screws: when properly placed, those are designed to place the bone around them, especially across the fracture joint, in compression so that the bone resonates at a specific frequency which induces bone growth.

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