Puzzle Box

[willstewart]

So this is  not challenging as puzzles go and is of very simple design - really an experiment to test the idea, but here it is.  The walnut box has a lid and two outer loose rings, each component held in place by a trio of pairs of 3*3mm dia magnets, as I often use.  To release the ring/lid one rotates to separate the magnets and lifts.  The 'puzzle' consists of the need to remove the two rings in sequence in order to access and remove the lid.

This works well but one does need to be careful placing the magnets, done here by using a compass and a turned plug that fits inside the box (with a marked centre) and the indexing system on the lathe. The nominal 3mm drill is carefully sanded to give a tight fit but the magnets (from first4magnets) are also glued.  Light oil finish.  Some markings still show that could be sanded off.

Why two rings?  Well really a consequence of how it is made - from a 90mm dia 70mm long cylinder held in 'giant' chuck jaws, from which first the outer ring plus lid are cut from one layer, then the box body, and lastly the inner ring, this cut from both sides of the residue after reversing in the chuck.  So not much waste but a certain amount of tidying needed on a disk sander.

[Bryan Milham]

An interesting idea, unfortunately the construction makes the inner storage area quite small, unless you hollow underneath.

But I think from your description, this is a first go, and you are already thinking of the next iteration.

[willstewart]

dr4g0nfly - yes it is small - suitable for teeth or earrings perhaps, but with care it could clearly be larger.  The main objective was to see how it worked (for example is it really hard to get the lid off without removing the rings first - yes it is) and to see if the magnet placement accuracy was an issue (on the whole OK).  And two rings was unnecessary maybe.  So in another iteration this would be different.  I may also re-sand the surfaces to get a better finish!  And think about using arrays of up-down magnets to get some kind of opening 'code' or rotation selectivity. 

FTR this does show the limits of what can be done with photos - one needs to feel it to get an idea.  This will be even more true of another planned project on an exponential loudspeaker horn (turned of course)!