Rocking Ship

[gleber]

I saw a rocking ship grandmother clock on FB Marketplace and it inspired me to investigate the possibility of making one.

I drew up some sketches and have been experimenting with some ideas. It's time to get some input and feedback from some of you. I plan to have 5 layers - the front and back frames, two rows of moving waves and a ship that will rock in the opposite direction of the waves.

Here are some sketches. I was originally going have waves in the front and back of the ship (as seen in the sketch), but for scale, I think having both in front would be better - the front row will be larger and move more than the back to also add to the depth perspective.


I bought this movement/dial from Merritt's (I didn't want to hack up a complete clock). The dial is 12" x 12". I plan to make the frame something like 12" x 9". I think I want rectangular rather than a semicircle, but going back and forth on that.



Side note: I get Ja_ Farr, Bromyard, but I can't make out the 3rd letter. I found a James Farr, Bromyard, so I assume the same, but wondering how they abbreviated James? Maybe it's just Ja, but it looks like there is another letter there? Appears to be 19th century - any other insights or links appreciated.

Anyway, here is a video of 1 row of waves and the ship prototype. It's just a prototype (I felt compelled to stress that).


The wave is hung from threads on each end so there is very little friction - mostly just inertia. This ship is mounted on a straight pin and balanced, also with little friction and so it does not have a tendency to lean in one direction more than the other. I'm using aluminum from a soda can and it bends easily and is hard to cut inside corners.

So, one question I have is does anyone have any ideas how to cut thin sheet metal with intricate details? We have a laser cutter at work, but it's not powerful enough to cut metal - I'm told it's too reflective and you need a lot more power. I could use thicker metal, but want to keep it lightweight and thicker will be harder to cut (but probably bend less).

Thanks,
Tom

 

[bruce linde]

cool project...

 

[gmorse]

Hi Tom,

Maybe it's just Ja, but it looks like there is another letter there?

The common abbreviation for James was JAs, with the 's' as a superscript. There are some exceptions, ('JNo' for John for instance), but the usual pattern was the first two letters of the name followed by the last as a superscript.

Regards,

Graham

 

[novicetimekeeper]

That's a very nice early painted dial, pre 1800.

I had a movement with a rocking ship. The movement is around 1690, the ship the end of a poker added late 20th century. As long as no permanent damage is done to movement or dial it sounds like an interesting project. I do have a spare ship if you want one

 

[novicetimekeeper]

here is mine


anonymous 17th century outside countwheel 8 day

 

[gleber]

Hi Tom,



The common abbreviation for James was JAs, with the 's' as a superscript. There are some exceptions, ('JNo' for John for instance), but the usual pattern was the first two letters of the name followed by the last as a superscript.

Regards,

Graham

Thanks g.

I believe you are right. There is a faint letter and I thought it was just the top of a missing one, but now I believe it is a superscript "s."

Tom

 

[gleber]

As to cutting the sheet metal, have you someone doing water jet cutting nearby?

Water jet cutter - Wikipedia

Thanks roughbarked.

We don't have a water jet cutter at work, but we have used a local shop for waterjet cutting on occasion and I'll check with them.

Tom

 

[gleber]

That's a very nice early painted dial, pre 1800.

I had a movement with a rocking ship. The movement is around 1690, the ship the end of a poker added late 20th century. As long as no permanent damage is done to movement or dial it sounds like an interesting project. I do have a spare ship if you want one

I haven't figured out how to attach the whole contraption to the clock yet, but I plan to do it with some kind external frame off the seat board and/or clamps to the movement pillars so I don't have to alter the movement or dial. The seat board is newer and warped, so it needs to be replaced anyway. I will also add a collar to the anchor arbor for the ship's crutch, but that can be removed as well.

I appreciate the offer of the ship, but this one is a matter of pride for me to accomplish the whole thing. I would like to see a photo of your ship if you can post one.

Tom

 

[gleber]

here is mine


anonymous 17th century outside countwheel 8 day

Simplistic, but I like it. It looks like the ship was cast? You said "had..." Do you not have it anymore?

Tom

 

[novicetimekeeper]

Simplistic, but I like it. It looks like the ship was cast? You said "had..." Do you not have it anymore?

Tom

When I say had I mean it is no longer on the movement. It was fitted by grinding a flat in the arbour and making a clevis on the end of the rod with a screw to fix it on the flat. The flat was the only damage and fortunately the arbour was substantial.

The movement is away for restoration, it was accepted by the restorer despite the damage. (he picks what he wants to work on, I only suggest clocks that might interest him)

The details are in the thread but here is the Victory

https://mb.nawcc.org/data/attachments/395/395400-a752147af3d129a17c6498d29ab4db11.jpg

 

[P.Hageman]

Tom, lets rock! I think it will be a nice project, lot of succes!

 

[gleber]

Working through some more prototypes... I cut the front and back steel and did a quick paint test. I will be adding more depth/detail to the tree, grass and waves, but I like how it is going so far.

There will be two rows of waves that move back and forth in front of the ship.



Tom

 

[gleber]

Another step... I created the two sets of waves:



I noticed that they have different natural periods because the front row is lower (longer pendulum). They are hung from the top on threads. I plan to "drive" them using yokes at different distances from the anchor arbor so the front larger waves will move further to help simulate depth. But watching this, I foresee frequency interferences due to the "pendulum" length differences. I'm not sure how much of an impact that might have, but my plan to solve that is to lower the top thread anchor point for the front row so the effective length is the same as the back row. I should be able to get the frequencies pretty close to matching by doing that.

Next step: remake the ship a little larger and mount it. It will rotate on a pin, so it will rock 180 out of phase with the waves, which I think will look appropriate.

I also realized that painting waves on the front frame was a bad idea. I originally had a rock on one side and tree on the other. Now I remember why... I can move the tree some to fix that side, but need to do something on the right so I don't have moving and stationary waves side by side at the same distance from the viewer.

This is a fun project, especially now that I'm seeing it come to life from my mind, then to paper and now in real life.

Tom

 

[Uhralt]

That looks like a fun project. Nice!

Uhralt

 

[gleber]

The engineering is mostly complete. I plan to tweak a few things. There will be a stationary row of waves just in front of the ship to cover the lower part.

Front:


Back:


Down at linkages from the front:




Next I will take it apart and repaint it before final assembly.

Tom

 

[Ralph]

Very nice and well thought out

Ralph

 

[novicetimekeeper]

That clock has one hell of a tick in a couple of those videos but in the other it sounds really good.

 

[gleber]

That clock has one hell of a tick in a couple of those videos but in the other it sounds really good.

Yes, there is a big difference when I attach this vs. the clock by itself. The noise is mainly from the rows of waves. They act like sound boards for gongs and amplify the impacts of the crutch posts with the wave slots. One of the tweaks I have in mind it to add a plastic slot instead of the slot directly in the sheet metal. That should reduce the sound. And, I was concerned about wear on the aluminum crutch posts anyway, so plastic should help with that too. I'll take a hint from R. Croswell and consider using something like Delrin AF he uses for woodworks bushings, reportedly with good success.

As it is, I hardly notice any change in the overswing with or without, so I am pretty happy that I seem to have kept the added weight and friction as minimal as possible. I could even be tempted to make the planned stationary row of waves in front of the ship into another moving row. It would only have to move very little being "further in the distance" and it is just as easy to hang it on threads as it would be to screw it to the back plane.

Thanks for commenting.

Tom

 

[Royce]

Tom,
What a cool clock. Great job!!
Royce

 

[gleber]

Thanks Royce. I'm hoping the final repaint will do it justice.

Tom

 

[gleber]

Another step closer. They say 2 heads are better than one, so three rows of waves must be better than two. And, I think I agree.



I think the three rows really adds to the depth of the scene and give the impression of the whole area of water moving, not just strips. From distant to near, each row moves a little more by about twice the amplitude. I also moved the ship forward a little bit and make it rock more, which I think also helps.

I had to remake the crutch, and now it's beginning to look more like a tree. Each post drives an element as labeled. The spacing between the posts for the waves is 1-1/2".



Tom

 

[gleber]

Finally, after a 2 year hiatus during covid and other project priorities, I have finished all the details and securely mounted the rocking ship and waves mechanism, made the clock modifications and its mounting, and fine tuned the overall operation. Here a few pictures of the details. The remaining tasks include painting the scene, restoring the cabinet base and making a hood.

Overview
Waves Mounting
Ship Mounting
Crutch Extension

You can watch a YouTube video of the motion here:

You can see more details of the design and construction on my website: Clock Repair & Restoration Rocking Ship Clock

Tom

 

[Ralph]

Glad to see you’re back.

Ralph

 

[gleber]

I have completed the scene painting and reassembled the mechanism for its first test run. You can see a video here:

Here is my website with more details on the design and construction: Clock Repair & Restoration Rocking Ship Clock

I am really pleased with the results. I now have to make a hood for the case.

Tom

 

[bpd]

That is wonderful and fun to watch (until I started getting seasick). Can’t wait to see the finished clock.

 

[P.Hageman]

Tom, what a marvellous job! Like the way the lady and the tree are situated in front of the rocking scene, well done imho.