Introduction into Puzzlemaking by Steve Strickland

[gibell]

But do you break the wood or the glued joint? It it is more flexible, it should be more difficult to break it (again scaling the applied force) ....

The problem is that with greater flexibility it is all too easy to apply too much force, snap!  The problem happens when the puzzle is taken apart, because unless the force is applied correctly, a piece gets over flexed.

I refer actually to plastic puzzle pieces that I have generated lately.  It is really easy to make these at any scale factor, and I have at least 4 different sizes now!

[Canuck]

I think 'scale' in puzzlemaking is so very important and often the only reason I will make a prototype of a particular design...sometimes only a fractional difference in stock will make the biggest difference in the overall size greatly affecting the 'desirability' of a puzzle...this probably doesn't fit into the past conversation but seemed to mesh somehow into it?  

[RKB]

in the meantime Ry replied with appropriate explanations, however I post anyway...

Yeah! And almost the same works for explaining why elephants have such big ears  

[Canuck]

Yeah! And almost the same works for explaining why elephants have such big ears  

Now would that be the 'Afrikaan' or 'Asian' elephants? 

[rolly_wood]

why elephants have such big ears  

Of course because Johan shouts so loud! 

[Johan Heyns]

You're wrong, its because of our noiseless talking that elephants have to have such big ears in order to hear what's being said about them!!

Of course because Johan shouts so loud! 

[rolly_wood]

 

[MarkMc]

Flexibility, or how much something deforms, is directly related to the object's moment of inertia, which in turn is dependent on the objects dimensions relative to the direction of the force being applied.  I.e. a floor joist is always turned on its edge to provide a higher moment of inertia and therefore more strength.

[rolly_wood]

Exactly, Mark. http://en.wikipedia.org/wiki/Bending#Simple_or_symmetrical_bending and to link your right remark to what George asked, and also to what said by Ry it is useful to notice that the bending is given by the lenght divided by the squared heigth of the beam. So scaling the structure, bending does not remain proportional but tend to diminish (become rigid) when the structure is bigger. If I am not wrong, of course.

[STP]

The other factor to consider in flexibility is the modulus of elasticity (or Young's modulus) of the material being used.  With plastics, you may have some range of choice, George.  If you let us in on what plastic choices you are considering, we can help look up values for E for each of the plastics...  Wood "E" values also vary from species to species...

Hope that helps!