Best Lego Ratchet Mechanism

Introduction: Best Lego Ratchet Mechanism


They are in a lot of everyday items and they are quite interesting.

I have wanted to make my own ratchet but after searching the net I couldn't find anything, so I have designed one and now I am sharing it with the world.

This is loosely based on a bicycle hub in the way that it has two spring-loaded pawls as the teeth, a normal bicycle will have 3 - 8 pawls on the hub but the Lego I am using didn't allow for a model of that size.

Anyways, lets get started!

Step 1: The Base

This is how to make the base of the model, it uses 2x 6x12 and 1x 2x6.

They are connected using the tiles like shown.

The tiles don't need to be identical, it just needs to be a flat surface for the ratchet to rotate on.

Step 2: The Ratchet Mechanism Part 1/4 BASE

This is very easy to build, the base consists of three layers and the two tabs on the very bottom connect the two 1x1 towers in the previous step, they in turn stop the tires from popping out of the model.

If you can make this connection stronger, do it - improvise all you like, I was running out of pieces so I had to leave it at what you see.

Follow the photos and once complete, put it all together

Step 3: The Ratchet Mechanism Part 2/4 CONNECTIONS

This step outlines the connections.

Each of the outer round 1x1's are used for connecting the pawls, the center 1x1 holds the tires in place.

Build this carefully, if you mess up the locations of the parts it won't work.

Step 4: The Ratchet Mechanism Part 3/4 PAWLS

This is the most complex step, it includes the pawls.

Because the pawls need to be spring loaded I had to search high and low for a solution because I don't have springs.

This is where my ideas came in yet again - I decided I would use Lego tires (did you know Lego is the biggest tire manufacturer in the world?!) The Lego tire has enough resistance to spring back after being squashed and it also has enough memory to stay in the round shape even after quite a while of being squashed.

You can use the tires as springs in a multitude of different ways but I thought this would be the best way to showcase them.

So follow the photos, if anything is unclear I still have some more Lego so I could rebuild a part of it.

The pawls need to be made precisely like shown in the photos or it won't grab the tire right or it won't fit in the hub.

This is my favorite part of the model so if anyone makes one please post an "I made it" comment!

The last three photos were an afterthought, it shows you the location of the tires when opening and closing the pawls.

Step 5: The Ratchet Mechanism Part 4/4 TOP

This step will show you how to make the top section of the ratchet.

The top needs the tiles to allow it to spin freely under the roof while keeping it centered.

This section goes down to the pawls, they are in the next step.

Step 6: How the Ratchet Connects to the Base

This step shows you how the ratchet connects to the base of the model, it uses a 1x2 offset plate that connects to the center of a 1x3 plate on the ratchet.

If you can't understand this step please comment and I will try my best to help you out.

Step 7: The Mini Decoration

This is how to make the 4x6 mini decoration, it is so simple - just follow the pictures and you should be able to make it.

It is not at all necessary so don't make it if you don't want.

Step 8: The Sides

This step will show you how to make the sides, it is fairly simple.

When you connect the sides to the top like shown in the second-last photo you need to be wary of the alignment, you should notice that there are two different ends to each side module, one is made up of 2x2's and the other is made of 2x3's.

Review the last photo to see the proper alignment.

Step 9: The Top

This is the top part of the ratchet that holds the axle in place, it is simple using only two 2X6's and one 2X8.

Put them together as shown and put aside, this will be the last piece to go on.

Thank you for taking the time to read/make this project, I hope you enjoyed it!

Please check out my channel and comment on stuff you like.

If you liked the idea of using the tires as springs, let me know and I will post another project with them.

I hope you have learned a few things from this, if so please share it with your friends!

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