Davidz90

A few more photos. The tower is in the same scale as Notre Dame cathedral (approximately 1:300), making it 570 m high. That would be second tallest building in the world and most massive one by far. The lowest level has interior, visible through the main entrance The clock mechanism is on a "balcony" below the face. Two driving weights provide pwoer for about 80 hours on one rewind. General layout is basically two towers connected with bridges, creating a sturdy H-beam like structure. Near the top, there are two knobs for rewinding and setting the time. One can also see one of the two large diameter wheels that support the driving weight. Nylon string unwinds from the central, white spool and goes around these wheels. This way, each driving weight is supported by a single, large diameter wheel, reducing friction.

It's done. That was a lot of work.

It's alive! Finally got to the clock part of this build. Pendulum (well, ugly placeholder) hangs in front, escapement is powered by two weights hanging in the recesses of the H-shaped structure of the tower.

Progress...

Unfortunately not. However, the general idea is the same as here: Magnet is used to close/open circuit. What gear ratio are you using? With 2 meters to the ground, runtime of 24 hours should be straightforward to do with something around 1:50.

Wow, this is absolutely fantastic! Beautiful use of Lego as a decorative element. Great job, and I'll wait for a full video :)

Recently I bought the Notre Dame cathedral set and noticed how good value per piece it has (granted, most of the pieces are rather small). I already had a substantial collection of tan pieces thanks to my clock tower that I wanted to improve. So, one irresponsible financial decision later: Armed with that (and a few separate brick orders), I have started a truly grand project. This clock tower will be more like an actual building, standing on a cliff. I want to strike a balance between a tower and a cathedral. The spike on the "balcony" at the front will point to identical spike at the end of the pendulum. This will be an easy way to make sure that the tower is leveled properly. In addition to a working clock mechanism, the tower will also have lights. Here's a sneak peek at the electrical system and initial tests The complete tower will be about 170 cm high. This is the lowest (and most massive) of three sections it will divide into for easy moving. Two weeks of building so far, this is gonna be a loong project.

Some time ago, I came up with an idea to encode numbers 1-12 in a compact manner: With this "crown wheel" I could realize a striking mechanism with a counting mechanism that is rigidly connected to hours hand and cannot get desynchronized, unlike chain-based solutions. Normally, this is called "rack and snail mechanism" but a sufficiently precise snail cam seems to be almost impossible to build. So here's the thing: There is a gear rack that gets dropped on the crown wheel shortly before full hour. Then, at full hour, mechanism is activated and lifts the gear rack one tooth at a time until it reaches predetermined upper position and stops the mechanism. How many rotations (=bell strikes) will that take, depends on the position of the crown wheel (and so, hours hand).

Chronograph with two hands seems to be rather problematic to do and I don't know how to make such a mechanism reliable. Besides, I have never seen chronograph with two hands. What exactly is your goal?

Looks fantastic!

Exactly. A reset mechanism that pulls the faster hand back by several rotations and puts it exactly at 0 seems really difficult to do reliably. It seems that adding a slip clutch between hands and using some lever arrangement like in the gray video, that independently forces both hands to 0 position, may be a better approach here.

Frankly, I have no idea.

There is no standard. Usually chronographs have only one hand that counts to 60 seconds. When using the same dial, second hand could show up to 60 minutes. But for that a completely different mechanism than the one I've built would be needed. Resetting would get rather complicated.

This is intended. There is no need for more than one rotation unless there are two hands.

I have found one more good explanation of how this works:

Sure, feel free to ask.

Unfortunately, I have no idea how it looks exactly. However, here is a mechanism I have built just now: I hope this will give You some ideas.

It seems that by pushing a button, he pushes some lever to a horizontal or vertical position. The lever is connected to the hand with some large gear ratio.

Two ways: 1. Weight on a string, hanging from a spool 2. Weight on a lever, connected to the hand with some high gear ratio.

Hi and welcome to the forum! Usually, in real clocks chronograph uses a whole set of special-shaped cams to do the job; see: https://www.fratellowatches.com/understanding-the-mechanical-chronograph/#gref That is difficult to do with Lego. However, a simpler option is to use a weight on a string or a pullback motor attached to the chronograph hand. Then, you need some sort of a clutch to: 1. Connect the hand to the clock. Hand goes forward and lifts the weight or winds up the pullback motor. 2. Stop the hand. 3. Disconnect the hand from the clock. Weight/pullback motor resets it.

Thanks!

Congratulations to the winners, top 2 is so close! Also, thanks for all the votes, way more than I expected :)

Now this is unique! I wonder if the linkages to the wing tips could be altered so that the wingtips perform more of a flapping motion instead of keeping constant angle, which seems a little unnatural.

A little hybrid between a pendulum and balance wheel. Basically, the vertical part acts as a pendulum and the wheel adds inertia to slow it down. The result is a very compact, if inefficient, mechanism.

Wow, that's really unique! Never heard of such machine.