Can a mechanical clock be made on the Glowforge?

Ever since I got my :glowforge: I have wanted to try to make my own mechanical clock.

After just a little research, I realized how difficult that is to do and to tune it to get it right. So, I tossed the idea on the backlog and moved on to other ideas…

Now that I have more experience with my :glowforge: and what it CAN do, I am thinking about trying this. I know that my clock might not hold great time, or might need to be winding every day (or multiple times a day…) but I think it would look cool – even if it didn’t necessarily “work” like a real mechanical clock.

Has anyone else attempted this with their :glowforge:? I searched the forum, and found a lot of talk about clock faces, but not a single entry about working mechanical clocks. Some mechanical motion devices, but nothing that actually attempted to keep time. (I assume this is because of the complexity of the subject.)

If I do attempt this, I know the chances of it working are very slim because this is a very difficult and precise task. But, think it would make for an interesting art piece (even if it doesn’t work).

Edit: Progress is being made! (Join the conversation!)

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There are several mechanisms on Instructables, but one guy has a project writeup that includes all the theory and research and you could use that to designing your own pretty much from scratch.

It appears a pendulum is the best way to get any type of accuracy with “rough” construction techniques.

I’d also highly recommend Clickspring’s series on constructing a skeleton clock.

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My research agrees with that sentiment. I think a pendulum clock is the way to go.

The escapement mechanism is what I have been trying to figure out. Seems there are several ways to do it.

I will check out that link from Clickspring. I have also been looking at this design from Stephen Ressler.

Edit: Wow, so much information in those Clickspring videos! I would love to attempt a spring mechanism for some clockwork toys at some point, but I think and going to go weight and pulley route for my first attempt at a clock.

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Well, I have Sketchup but apparently that site doesn’t recognize my account.

Here is the previous link: https://stephenjressler.com/diy-engineering/

The clock is project number 15.

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Personally, I’d start with Brian Law – although his designs generally assume thick plywood, you can make that up by layering:

…then, when those are boring, get a copy of Gearotic and design one from scratch. I used Gearotic to design my orrery, and while it’s very idiosyncratic software there’s pretty much nothing else like it:

http://gearotic.com/

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Thanks! I remember looking at some of his stuff early on in my investigations.

Have you ever attempted one? Or is that just where you would start if you were going to?

I went with Clayton Boyer instead:

https://www.lisaboyer.com/Claytonsite/Claytonsite1.htm

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Yes! I remember looking at those designs also!

Also, if you have a decent source of cast acrylic (like Chemcast scraps from TAP), acrylic is much nicer to work with than wood, as long as you’ve got the right glues (it takes a variety; I like UV glue for adhering to metals, for example). Most of these designs can be pretty easily adjusted to use different thickness of material, as long as all materials are the same thickness (so using 0.20 acrylic is no harder than using the originally-specified 0.25 plywood).

No char to deal with on cast acrylic…

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I will definitely keep that in mind!

I am playing draftboard to begin with. I found it to be sturdier than ply, and still cheap to play with.

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Looking I see all those that other folks have noted, Looking that the place I wanted was Brian Law’s clocks that I found most impressive and I think he is selling a book with the theory and math.

I believe there was someone who bought and built one of Law’s designs.

If you are looking for something to keep time, then there are plenty out there far better than any mechanical clock. Growing up it was commonplace for folks timepieces to be many minutes different, even when set to be the same. but that was before fancy electronics were commonplace. I had at one time a black forest flying pendulum cock that could be ahead and behind the actual time within the same hour.

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Hey, this may be more up your alley!

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That is awesome! I have seen the ball-clocks before, never seen instructions for them, thanks!! I will have to give that a try sometime (added to the backlog).

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I have been thinking about designing a laser-cut clock for a long time.

Many years ago, I took a hint from Eric Harshbarger, famous for his LEGO Grandfather Clock. He noticed a new LEGO piece that he suggested would make an excellent escapement gear. So I designed my own fairly compact weight-driven, pendulum clock mechanism out of LEGO. I then built the whole thing into a small clock tower with 4 working faces for a club train layout.

I learned a lot doing it. The main thing that helped was to modularize the design into three functional subsystems. The drive was originally a hanging weight, but I eventually replaced it with a slow-running motor. The escapement and initial gearing block supported the pendulum. The output from the first stage was fed into the clock face, which had the gearing to run hour and minute hands.

The main thing I learned (aside from a bunch of theory) was that reducing friction is the key. You want to expend as little energy from your weight or spring as possible over time, and you generally need a lot of reduction. I found it helped to minimize the number of gear stages and pay close attention to squaring things up during assembly.

I also put a friction/slip gear between the escapement output stage and the clock drive so the time could be set just by moving the minute hand without the need to disengage a gear.

I think once people here see how easy it really is to build a clock, we’ll see some really creative timepieces.

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The research I have done completely agrees with everything you said! I just have not experienced it for myself yet.

I hope to do several smaller tests to see how feasible some of this is to do with the :glowforge:.

I think axles are my biggest concern right now. I don’t think it is feasible to use an axle cut from the :glowforge:. I think I will have to source those externally. Looking at trying dowel rods. Small enough to reduce friction surface, but hopefully strong enough to hold together.

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Suggest brass rods, as much as it may pain you…

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I will have to look for some brass rods. I am going to play with the dowels for now, just to get used to physics first. Then I may move up to sturdier materials.

Oh, you can also get acrylic rod. That may be less of a departure…

That could be interesting, but I would be concerned that it would snap more easily than the others at smaller diameters?