<p>The <a href="http://brickset.com/sets/9679-1/AT-ST-Endor" rel="nofollow noreferrer">AT-ST &amp; Endor (9679)</a> uses cogged connectors (<a href="http://brickset.com/parts/4210884" rel="nofollow noreferrer">4210884</a> + <a href="http://brickset.com/parts/4211803" rel="nofollow noreferrer">4211803</a>, I don't know if the combination of both parts has a name) for the legs. These connectors are pretty strong for their size, they may be sturdy enough for your model if it's not too heavy.</p>

<p><a href="https://i.sstatic.net/EfKtI.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/EfKtIm.jpg" alt="enter image description here"></a></p>

<hr>

<p>For bigger constructions and higher degrees of freedom, beam with balls and cups can be used, they allow rotations and movements in two axis. For example, the <a href="http://brickset.com/parts/4593555" rel="nofollow noreferrer"><em>Beam A 5M Ball/Cup Ø10.2</em></a> (they are other <a href="http://www.bricklink.com/catalogList.asp?pg=1&amp;catString=749&amp;catType=P&amp;v=1" rel="nofollow noreferrer">similar parts on Bricklink</a>):</p>

<p><a href="https://i.sstatic.net/6zrPg.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/6zrPg.jpg" alt="enter image description here"></a></p>

<p>For example, <a href="http://brickset.com/sets/75112-1/General-Grievous" rel="nofollow noreferrer">General Grievous (75112)</a> arms and legs can be adjusted in many ways:</p>

<p><a href="https://i.sstatic.net/wRRsf.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/wRRsfm.jpg" alt="enter image description here"></a></p>

CC BY-SA 3.0
2016-08-24T12:44:25.447Z
Thanks, that is already a good start. However, I also need parts moving on multiple axis (like a human hip or shoulder for example). Any suggestion ?
z3r0
CC BY-SA 3.0
2016-08-24T12:56:19.180Z
@z3r0 I added the balls and cups, I hope that it won't be too big for your models.
A.L
CC BY-SA 3.0
2016-08-24T13:00:04.983Z
Thanks for the idea, unfortunately those parts are _way_ too big for what I intend to do. Do you happen to know any alternative ? Other than that, the cogged connectors seem a rather interesting concept for mono-axis (is it even English ?) articulation.
z3r0
CC BY-SA 3.0
2016-08-24T12:37:15.090Z
2016-08-24T12:55:42.720Z
2016-08-24T12:55:42.720Z
A.L
<p>You could use the plate ball and cup joints like <a href="http://brickset.com/parts/6043656" rel="nofollow noreferrer">6043656</a> and <a href="http://brickset.com/parts/4239654" rel="nofollow noreferrer">4329654</a> (and a few other parts with balls that will fit)</p>

<p>These parts:
<a href="https://i.sstatic.net/2Va2p.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/2Va2p.png" alt="enter image description here"></a></p>

<p>One caveat though, brick #2 from the left does not have much sturdiness in holding joints together. 1, 3, and 6 are good though.</p>

CC BY-SA 3.0
2016-08-24T13:11:28.567Z
The two small ones in the middle of the picture seem to have size characteristics close to what I'm looking for. Do you happen to know if that specific ball-cup combination has friction (allowing specific poses) ? If I remember correctly, the other ones don't. Also, do you know if the 1x1x1 ball holder also comes in different shapes (1x2x1 like its left neighbour) ?
z3r0
CC BY-SA 3.0
2016-08-24T13:21:02.403Z
@z3r0 From experience, the two in the middle do have enough friction, however, there is no 1x2x1 for that piece.
SMS von der Tann
CC BY-SA 3.0
2016-08-24T13:42:36.957Z
Well, I guess I'll try to find some ball-cup combination somewhere to test their _friction_. Could you please write the designation of the two parts in the middle ?
z3r0
CC BY-SA 3.0
2016-08-24T13:48:44.620Z
@z3r0 14704 for the 2x2x1 socket and 3614 for the 1x1x1 with ball.
SMS von der Tann
CC BY-SA 3.0
2016-08-24T21:42:12.960Z
In my experience, #5 from the left, when paired with #1 or #6, has no friction worth mentioning.  I don't know about the other pairings.
Mark
CC BY-SA 3.0
2016-08-24T13:03:42.490Z
2016-08-24T14:40:49.530Z
2016-08-24T14:40:49.530Z
SMS von der Tann
<p>I think the best technique for building a sturdy Lego structure is to start with a wide and big base and then stack up with smaller bricks. I took part in a Lego challenge and one of the challenges was to build a big Lego tower. So, I decided to start with a big base. Then, I built up with smaller bricks. When I did my test to see which was the best, I found out that a bigger base is better. I also am doing a science fair on which Lego structure is strongest when dropped. I haven't done it yet but I believe that a square base will be the strongest instead of the other bases I have chosen. I love building with Legos but a big pet-peeve is when they break. That is why I am doing my science fair experiment to see which structure is the best. I will let you know when I have my data.</p>

CC BY-SA 4.0
2020-10-05T14:57:12.427Z
2020-10-05T14:57:12.427Z
Evan
<p>So I have been using <em>LEGO®</em> for a rather long time and over the years, I started going towards small constructions. While doing this, I began building rather small robots (<em>Mobile Frames</em> for those who know), between ~8cm and ~11cm or approximately 8 to 11 studs.</p>

<p>Those mechs I build are articulated and I want them to have as many articulations as possible (<em>e.g.</em> a leg should have a hip, a knee and an ankle, not only a hip). <br/>
The problem is the sturdiness of the whole construction. I have tried multiple options and the articulations are often either too weak to stay in position correctly or too fragile to support other parts, leading to structure vulnerability and eventually <em>destruction</em> of either portions of or the whole robot.</p>

<p>My question is the following : do you know any <strong>compact yet sturdy articulation building technique</strong> or any small articulation part ? <br/>
Bonus : if you can provide a method allowing me to build more or less <em>on</em> the articulation (not sure if that's very clear).</p>

<hr>

<p><em>EDIT</em> : For posing reasons, the articulation needs to have some 'friction' to keep a specific angle.</p>

<hr>

<p>Should there be any problem with the question (wrong formulation, bad English, need for clarification), please don't hesitate to point it out.</p>

CC BY-SA 3.0
2016-08-24T14:57:13.827Z
This doesn't actually answer your question, hence the comment as opposed to an answer, but for larger constructions the 24-tooth clutch gear works well.
TLW
CC BY-SA 3.0
2016-08-25T07:04:11.403Z
Well, building tricks are always welcome, especially when it comes to _LEGO®_.
z3r0
<building>
Articulations : which technique to use on small constructions for sturdiness?
z3r0
# Articulations : which technique to use on small constructions for sturdiness?

(Asked by: username_0 on 2016-08-24)

So I have been using *LEGO®* for a rather long time and over the years, I started going towards small constructions. While doing this, I began building rather small robots (*Mobile Frames* for those who know), between ~8cm and ~11cm or approximately 8 to 11 studs.

Those mechs I build are articulated and I want them to have as many articulations as possible (*e.g.* a leg should have a hip, a knee and an ankle, not only a hip).   
The problem is the sturdiness of the whole construction. I have tried multiple options and the articulations are often either too weak to stay in position correctly or too fragile to support other parts, leading to structure vulnerability and eventually *destruction* of either portions of or the whole robot.

My question is the following : do you know any **compact yet sturdy articulation building technique** or any small articulation part ?   
Bonus : if you can provide a method allowing me to build more or less *on* the articulation (not sure if that's very clear).

---

*EDIT* : For posing reasons, the articulation needs to have some 'friction' to keep a specific angle.

---

Should there be any problem with the question (wrong formulation, bad English, need for clarification), please don't hesitate to point it out.

**Tags:** building

> **Comments:**
> **username_1**: This doesn't actually answer your question, hence the comment as opposed to an answer, but for larger constructions the 24-tooth clutch gear works well.  
> **username_0**: Well, building tricks are always welcome, especially when it comes to _LEGO®_.  

---

## 3 answers

### Answer by username_2 on 2016-08-24. Score: 5

The [AT-ST & Endor (9679)](http://brickset.com/sets/9679-1/AT-ST-Endor) uses cogged connectors ([4210884](http://brickset.com/parts/4210884) + [4211803](http://brickset.com/parts/4211803), I don't know if the combination of both parts has a name) for the legs. These connectors are pretty strong for their size, they may be sturdy enough for your model if it's not too heavy.

[![enter image description here](https://i.sstatic.net/EfKtIm.jpg)](https://i.sstatic.net/EfKtI.jpg)

---

For bigger constructions and higher degrees of freedom, beam with balls and cups can be used, they allow rotations and movements in two axis. For example, the [*Beam A 5M Ball/Cup Ø10.2*](http://brickset.com/parts/4593555) (they are other [similar parts on Bricklink](http://www.bricklink.com/catalogList.asp?pg=1&catString=749&catType=P&v=1)):

[![enter image description here](https://i.sstatic.net/6zrPg.jpg)](https://i.sstatic.net/6zrPg.jpg)

For example, [General Grievous (75112)](http://brickset.com/sets/75112-1/General-Grievous) arms and legs can be adjusted in many ways:

[![enter image description here](https://i.sstatic.net/wRRsfm.jpg)](https://i.sstatic.net/wRRsf.jpg)

> **Comments:**
> **username_0**: Thanks, that is already a good start. However, I also need parts moving on multiple axis (like a human hip or shoulder for example). Any suggestion ?  
> **username_2**: @username_0 I added the balls and cups, I hope that it won't be too big for your models.  
> **username_0**: Thanks for the idea, unfortunately those parts are _way_ too big for what I intend to do. Do you happen to know any alternative ? Other than that, the cogged connectors seem a rather interesting concept for mono-axis (is it even English ?) articulation.  

---

### Answer by username_3 on 2016-08-24. Score: 3

You could use the plate ball and cup joints like [6043656](http://brickset.com/parts/6043656) and [4329654](http://brickset.com/parts/4239654) (and a few other parts with balls that will fit)

These parts:
[![enter image description here](https://i.sstatic.net/2Va2p.png)](https://i.sstatic.net/2Va2p.png)

One caveat though, brick #2 from the left does not have much sturdiness in holding joints together. 1, 3, and 6 are good though.

> **Comments:**
> **username_0**: The two small ones in the middle of the picture seem to have size characteristics close to what I'm looking for. Do you happen to know if that specific ball-cup combination has friction (allowing specific poses) ? If I remember correctly, the other ones don't. Also, do you know if the 1x1x1 ball holder also comes in different shapes (1x2x1 like its left neighbour) ?  
> **username_3**: @username_0 From experience, the two in the middle do have enough friction, however, there is no 1x2x1 for that piece.  
> **username_0**: Well, I guess I'll try to find some ball-cup combination somewhere to test their _friction_. Could you please write the designation of the two parts in the middle ?  
> **username_3**: @username_0 14704 for the 2x2x1 socket and 3614 for the 1x1x1 with ball.  
> **username_4**: In my experience, #5 from the left, when paired with #1 or #6, has no friction worth mentioning.  I don't know about the other pairings.  

---

### Answer by username_5 on 2020-10-05. Score: 1

I think the best technique for building a sturdy Lego structure is to start with a wide and big base and then stack up with smaller bricks. I took part in a Lego challenge and one of the challenges was to build a big Lego tower. So, I decided to start with a big base. Then, I built up with smaller bricks. When I did my test to see which was the best, I found out that a bigger base is better. I also am doing a science fair on which Lego structure is strongest when dropped. I haven't done it yet but I believe that a square base will be the strongest instead of the other bases I have chosen. I love building with Legos but a big pet-peeve is when they break. That is why I am doing my science fair experiment to see which structure is the best. I will let you know when I have my data.


---

