What is the strongest LEGO structure?
(This is a general "strongest LEGO structure" question. Using the structures in building the computer case is just an example of applications.)
To make it more challenging (and more perfect), the case will have handles (like this type) for carrying the whole thing around, and it will have "legs" (like this bar type) to lift the whole case up for ventilation.
For better reference, here is the coordinate notation:
There are 4 parts (for now I can think of) in the case which has to encounter different types of strength challenges:
For the white bricks, they do not require special strengths, do they?
FYI, here are the LEGO dimensions:
Horizontal pitch, or distance between knobs: 8mm.
Vertical pitch / Brick thickness: 9.6mm.
The horizontal tolerance: 0.1mm.
Plate thickness: 3.2mm.
Above is the common information across the 4 questions.
Below is the question for this specific part.
(1) The pillars (Red)
The pillars do not have many requirements while the PC case is sitting still on the table. But when the PC case is lifted up by holding the handles, the pillars become critical to support the weight of the entire PC.
Normal stacking up the LEGO bricks or plates must not work. The bricks/parts will be separated very easily.
What is the strongest LEGO structure when using as Pillars?
I have come up with a structure (below left). I pile up the plates along the Y axis. So when tension is applied to the pillar, the knobs (many knobs) will lock each others, such that (as long as the LEGO plates themselves do not break) the pillar will not break into two parts.
There is a problem. Although the pillar will not be pulled apart along the Z axis, the plates might be separated along the Y axis due to the tension. So I made a "doughnut" to secure the pillar (below right). When the pillar wants to separate, it is a force along the Y axis. The knobs of the "doughnut" will (hopefully) act against forces of X and Y axis.
5 plates (3.2 x5 = 16mm) = 2 pitches (8 x2 = 16mm), so the pillar fits exactly in the "doughnut" (with 0.2mm (Y axis) & 0.4mm (X axis) tolerance).
Such that, the pillars have to be 6 pitches thick, which is 4.8cm. If this structure is possible, can we make the "doughnut" 1 pitch thick, and the pillar 4 pitches thick?
I assume using longer plates will be better than short plates, because fewer gaps along the Z axis, lower risk to separate, isn't it? However, I believe more plates stacking up along the Y axis, which will have more knobs, will make the pillar stronger. Which means using plates here is better than using bricks, isn't it?
In this PDF page 4, that research suggests using pegs. Obviously, the number of pegs can be used in the pillar will be less than the number of knobs in my suggested structure. And I afraid the peg itself will break, as pegs are hollow plastic, while knobs are more "solid".
Which structure (the above one, the research paper one, or your suggestion) is the strongest?