"Loopy" in the English language means "mad or silly" or "having many loops". In the case of the Loopy Box puzzle, it is hardly the former (given its very difficult challenge quotient) but certainly the latter, as I shall try to describe below.
First off, its credentials; designed by Jean-Claude Constantin (now I haven't played with a JCC design for a long time, the last one in my hands was over 3 years ago; the Lock 250). It is also manufactured by him out of laser cut wood with the sides and bottom glued/screwed together to form a box. This puzzle was also Allard Walker's IPP35 Exchange Puzzle in Canada in 2015.
The puzzle measures about 11cm x 10.5cm x 7.5cm and is essentially a box with a lid that is "locked" in place by a piece of thick rope (see photo). Quality and construction is very good, typical of the JCC standard. The object is to open the lid and solve a second puzzle inside, a modified Hanayama Cast Claw that has an extra U-shaped piece linking the two claws.
In the last few years Allard Walker has had this habit of making puzzle exchangers work really hard by exchanging not one but two puzzles at the same time (usually one contained inside the other; see Conjuring Conundrum and Baffling Bolted Book). Well, he is a gentleman of means and can afford it... and I for one is certainly not complaining, since I am getting two separate puzzles from him in one exchange! The second challenge after the box is open is to take apart the Cast Devil.
Now back to the puzzle; as one can observe, the only sensible way of opening the lid would be to remove the length of thick rope. But unfortunately this is hardly that simple as I found out. The rope passes through a hole in a vertical slat and holds the lid down. The rope itself is attached in some way to a dial (and what's underneath the numbers and inside can't be seen clearly if at all, I tried shining a torch but it didn't help). It would be obvious that the dial (which can turn in both directions) has something to do with the rope's release.
I spent an estimated three to four days trying to disentangle and release the rope and even read Kevin Sadler's experience with the Loopy Box hoping to find some clues. But Kevin, like all good puzzle bloggers gave little clues on his blog and his photos didn't indicate anything of use either. Nothing worked and after some more trying I gave up and asked Kevin for a clue. He said he was too busy during that time and he also had to find his copy from his collection of several thousand puzzles. Not forgetting, he is a busy doctor and also. has Mrs S (which I had the privilege of meeting at IPP34 in London) to spend time with too!), He did mention that it involved quite a bit of dexterity and that was all I had to go on. I left the Loopy Box alone. Fast forward to the present after several weeks, and I had a go at it again, but still no luck. After trying incessantly, I contacted Allard for help this time. Now why did't I contact Allard in the first place back then??
When I saw the solution from Allard I said to myself - damn!, now why didn't I think of it? The way to remove the rope is pretty clever (I am sure those disentanglement puzzle experts would have quite quickly figured it out) but the physical execution of the correct technique is more than fairly difficult (even when you know exactly what needs to be done). Everything was pretty fiddly and my only criticism is that perhaps the dial and other parts could have been made larger to accommodate bigger fingers! After more than several minutes, I finally freed the rope and opened the lid to face the second puzzle!
Nope - I didn't go on to the modified Cast Devil and decided I will leave it for another day. For all those interested, the Loopy Box is available from Puzzle Master in Canada for CA$52.99 and from Puzzle Shop in Germany for 35 Euros.