Flight Case - Guest Post By Mike Desilets

Hi folks,

Here's the first guest post on my blog by puzzle collector from Hawaii, Mike Desilets.

Mike will be talking about a magician's trick box which also doubles pretty neatly as a puzzle box. Enjoy!

http://mechanical-puzzles.com/flight-case-guest-post-by-mike-desilets/

Haleslock 3

The Haleslock 3 designed by Shane Hales and exchanged by Peter Hajek during IPP37 in Paris, 2017. Very challenging!

http://mechanical-puzzles.com/haleslock-3/

Coke Bottle #4 - With Padlock And Chain

Update 23 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

The last time I played with a Wil Strijbos designed bottle puzzle was his very "burlesque" looking Limited Edition Dita Von Teese Perrier Bottle. And that was nearly two years ago. Dita Von Teese was a very fun solve in more ways than one! and certainly much easier than this Coke Bottle #4 (the latter according to fellow puzzle blogger Allard Walker's naming classification).

I have had the Coke Bottle #4 for quite a while now, I would say more than several years and just this evening decided to take it out to have a play (I still have about 4 more unsolved bottles including a opaque Coke Bottle, another of Wil's designs).

Coke Bottle #4 consist of a regular Coke bottle with a plastic cap, attached to it is a thick chain with a small padlock secured on the end. The padlock is inside the bottle and is restrained inside the bottle by a single chain link over the shackle (see photo). The chain link prevents the padlock from coming out of the mouth and the object is to unlock the padlock and take everything out.

Like most of Wil's bottle designs (and others), they look like impossible objects but we all know that its physically solvable of course; just that it may take a lot of effort and usually for impossible bottle puzzles, a fair (or even great) amount of dexterity. As you can see from the photo, you need the keys to unlock the padlock. I might add at this point that no external tools are allowed as well and you must work with only what you have been given with the puzzle. 

I did my usual bit of analysis to try to figure out the best way to unlock and remove the padlock. For a while I was getting no where and I was wondering if I am allowed to remove the set of keys from the chain. I had figured out what to do but couldn't solve the damn thing for a while with the keys still attached. I was rather impatient to get on with the puzzle so I emailed Wil Strijbos, Kevin Sadler and Allard (there's a time difference of about 7 hours between Europe and Singapore). I wasn't sure if either Allard or Kevin had solved the Coke Bottle #4 but figured at least one of them would be able to respond. Surprisingly I got a reply from all three gents within minutes of each other and all confirmed that the keys can be removed from the chain for the solve. Once I did this, I was able to unlock and remove the padlock within minutes; not too difficult I might add. Quite satisfied with my achievement I decided to leave the reassembly until the next evening. 

The difficult part came the next evening when I tried to reassemble everything back into the bottle. Like what I gathered from Allard and Kevin, the locking of the padlock back into the bottle was a real pain and caused many puzzlers untold amounts of frustration. 

Remember you can't use any "external" implements or tools, just what is provided with the puzzle. I had a fair idea how to re-lock the padlock and went about testing my theory. The re-assembly I must admit is very finicky and requires a great amount of dexterity, but its not something that is excruciatingly difficult to do. Not the kind of difficulty like when you can't solve a high level burr but the type where you know exactly what needs to be done, but you just can't seem to do it physically, given that you can only use what you have that comes with the puzzle. Nonetheless all ended well and I managed to lock the padlock again inside the bottle. Whew! 

Haleslock 2

Update 24 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

This is my 400th post! How time has flown by. And what better puzzle to write about than one coming from a really talented puzzle designer, Shane Hales from the UK. 

Shane started designing puzzles several years ago and I have had the good fortune to receive as gifts two of his very limited edition puzzles, first The Circle and later Turn The Plug. His puzzles are limited edition either because he produces only several of a particular design or he gifts them to friends. Until recently, Shane did not sell any but only gifted his puzzles to the lucky few. I am one of them lucky ones who got a Haleslock 2 as a Christmas present!

Recently Shane has progressed to producing puzzle locks. His works are not designed from ground up, example, in the style of Rainer Popp, meaning to say, he designs and produces a puzzle that looks like a lock, Instead, he goes the Dan Feldman way, where he uses existing commercial padlocks on the market and modifies them into a puzzle/trick lock. Shane's locks, the Haleslock 1 and Haleslock 2 were made available for a charity auction and sale respectively on his puzzle site but unfortunately for puzzlers, his Haleslock 2 are all sold out.

So coming back to the Haleslock 2...what is it like as a puzzle? Well, as I have alluded to, it is a typical looking padlock from a brand called Squire. The lock comes with two keys (one without any teeth as can be seen from the photo) and attached by a rather long chain to the shackle. The object of course is to un-shackle the lock.

I had read Allard Walker's blog post on how he had solved the Haleslock 2 and commented that it was "not extremely complex or complicated". For me personally, this couldn't have been further from the truth! I had solved Shane's previous puzzles, The Circle and Turn The Plug without too much frustration and without help, but for some (strange) reason, I could not solve the Haleslock 2 even after multiple sessions of playing over a number of days. Something was eluding me to the point I decided to ask Shane for not one, but two clues before I managed to figure out the first move...and the Hales Lock has four moves to free the shackle.

After the first move was done, everything else became easy and I released the shackle without a cinch. For me, the solution for the Haleslock 2 was totally unexpected. The "trick" (no pun intended) of the Haleslock 2 is IMHO a really a good one not easy to discover. With hindsight, I realized that I had missed something right at the beginning that I shouldn't have. Overall a great trick lock with an original and different idea/concept. Good work Shane!

Sliding Block Puzzle Locks

Some weeks ago puzzle collector Otis Cheng from China had mentioned on his Facebook post that he had acquired two sliding puzzle locks that had been designed by a group of students from a Beijing 12th grade middle school. The students had designed the locks with the help of their teacher who happened to be a puzzler! 

I thought they look pretty impressive and a rather unique approach to a puzzle lock design. But thanks to Otis I managed to get my hands on two such puzzle locks when I met him at IPP36 in Kyoto this August.

Both lock designs were adapted and eventually mass produced by Mi-Toys. The two locks are about the same size measuring 11cm x 7.5cm x 1.5cm (including the shackle) with one a tad smaller than the other. They are layered and formed together with laser cut wood. The moving blocks within are covered by a clear acrylic cover with cut-outs sufficient for the acompanying key to aid in moving the blocks around inside the lock. Fingers would be too big for this puzzle...so the key actually serves a useful purpose here!

The shackle of each lock is restrained by the blocks inside the lock. Both puzzles work on the principle of sliding blocks and once the blocks have been moved into their intended final positions, the shackle extends upwards and is freed.

Of the two puzzles one is relatively easy while the other (with more pieces) is quite a bit harder. While travelling back to Singapore from Kyoto, I took the opportunity to play with both locks and thankfully managed to solve both during the one hour domestic flight from Osaka to Tokyo. Hence you will notice the less than acceptable photos of the solved puzzles as they were both solved on my lap during flight.

An interesting take on the traditional sliding block puzzle or puzzle padlock, or both, whichever way you choose to see it. As of this post, I can't seem to find them on the Mi-Toys site but I think eventually they will make their way there.

Turn The Plug

Name
Turn The Plug

Designer
Shane Hales

Manufacturer & Availability
Hand-crafted by Shane Hales.

Type & Classification
Trick/Puzzle Lock

Dimensions
This a large and heavy puzzle measuring 14.5cm x 5.8cm x 10.2cm (inclusive of the base).

Materials & Construction
The block where the door lock is attached to is made from both Oak and Walnut. The lock itself looks to be the type of lock you will typically find on an office door. Affixed to the side is an ordinary looking key. Both lock and key comes from ERA, a manufacturer of door locks and components. Overall construction fit and finish is very good.

Overview
This is an "Interval Puzzle" from Shane. On Shane's puzzle site this is what he says:

"Smaller simpler puzzle designs.

I have decided to create some simpler puzzle designs while i'm working on my next project. Something easier for me to make, and also keeping everybody else's excitement alive!  Anyone that knows me knows i love locks! 
So i have created my Interval puzzles"

Turn The Plug is also my second puzzle from Shane, the first being The Circle, a great puzzle I reviewed just over two years ago on this blog.  

Shane does not sell these Interval Puzzles nor any of his "main" project puzzles, the latter which he makes just four copies at time; preferring to gift them to other close puzzler friends. The only exception was his very popular Hales Lock #1 which sold out within days of launch. 

The object of Turn The Plug is to "move the black dot on the back from "locked to "Open". Nope, you can't try to turn the knob with the black dot with you fingers, it won't work. The puzzle comes with a key that is attached to the side of the wooden block. So as not to create any spoilers here, nothing more about this key shall be mentioned. Also, no force or banging whatsoever is needed

It is obvious the lock has a part to play in the solving. This is one of those puzzles you can't say too little nor too much without giving anything away. Suffice to say, the solution has a few tricks up its sleeve and I got no where for a while, before discovering how to move the black dot to "Open"

Difficulty
For an experienced puzzler, I won't say its very difficult, but as mentioned, certainly a tad tricky and like all puzzles of this nature, some experimentation here and there is required before one gets the A-ha moment. For novices, well, that's another story.

Summary

An very nice design concept; with Shane using commercially available products and parts to fabricate into a great working puzzle. 

Open Lock

I have been after Gary Foshee's Open Lock for some time now, having missed one of Wil Strijbos' puzzle sales a couple of years back. Fortunately during IPP35 while I was exchanging puzzles with Gary during the Puzzle Exchange, I casually asked him if he had any Open Locks available and he said "go ask Wil". I didn't wait. I stopped my exchange temporarily and rushed over to Wil to quickly reserve one. In situations like this, time waits for no puzzler. Lucky for me I was one of the first, because that same night, he had sold out all the Open Locks he had.

Gary's Open Lock (also called the Transparent Lock) is just what the name says; its a naked lock with everything (well almost everything) showing. Its a pretty large lock measuring about 12 cm from the bottom to the top of the shackle and roughly the body is about 2 cm thick. The lock is made of aluminium while the shackle is forged steel. Gary doesn't make many of these because its very difficult to manufacture and so the numbers available are usually very limited and consequently, very expensive as well. In case you didn't know, the Lunatic Lock, which is commercially available was also designed by Gary Foshee.

The Open Lock can best be described as a "sequential discovery" puzzle. Meaning that you have to open the Open Lock (no pun intended) with nothing else but tools and implements that come with the lock. No external tools are permitted. In the case of the Open Lock, there is only the T-shaped hex key, instead of a key. 

The Open Lock shows its insides (of course it does!). And you will note that the shackle is locked in place by two horizontal bars, a thin one nearer the top (visible in the bottom photo) and a thick screw threaded rod at the bottom. It is obvious that these two rods must give way for the shackle to be pulled upwards and freed.

Here is where the sequential discovery part of the puzzle is. The solve is not difficult (certainly not the level of difficulty of the Popplocks), but tricky with some surprises (and A-ha moments). One has to use whatever tools available and do various tasks along the way to finally get the shackle unlocked from the body. Although it takes about seven steps to remove the shackle, it still takes a fair amount of time to complete the entire solve and to re-assemble everything.

Overall a very fun and entertaining puzzle lock which does not disappoint. Experienced puzzlers would have no problem with it. Unfortunately it seems that they are only available every couple of years and in very small numbers, very much rarer than Popplocks. So the only way to is to buy privately or through auctions, if at all they show up during the latter.

Popplock T9

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The T9 from Rainer Popp came out sometime in the middle of last year. At a behemoth 11.5cm x 7cm x 2.4cm and weighing in at 1.052kg, this is one of the largest locks in the Popplock collection. 

For previous reviews of Popplocks from T2 to T8, please click below:-
1. T2
2. T3
3. T4
4. T5
5. T6
6. T7
7. T8

Rainer manufactures and produces by hand a new model Popplock every year. I have had this lock since last August and its been in storage until several days ago. There have been two reviews of the T9 so far, from Allard and Kevin and both bloggers have sung high praises of the T9. Even though I only managed to solve mine with the help of the instruction manual, I have to agree with the two gents. It is really quite magnificent from a puzzling perspective.

There is really nothing more to be said about the T9's quality and finish. A real piece of superb craftsmanship with fine detailing. Damn expensive I might add. The body is made from a block of solid brass and the shackle is stainless steel.  At first glance, it looks like a large garden variety padlock with an ordinary looking key...except the front of the T9 has, in addition to the a key hole, a circular looking dial with rivets on the front, three of them imbued with red paint.

To solve the T9, there are basically three main stages, each with a number of steps. In most sequential discovery puzzles, the first step is usually easier (not easy) than the rest, but in the case of the T9, I was actually stumped right from stage one. Took me a while to figure out what needed to be done. Yes, the key can go inside the hole and turn round and round, but that's all to it, nothing more. With my small victory at stage one, I moved on to stage two. I had a good idea what was going on and even made progress (mind you all the while not being able to see what's happening inside the lock). However, I never made it completely past stage two. Here is where I was stuck for good and finally resorted to the instructions.

Stage three is even harder than stage two. And as Kevin mentioned in his post, you need good lighting. I would also add a good eye and make sure you have your reading glasses on too for this stage. I recommend playing under white or tungsten lighting if possible. The crucial steps in stage three are so very subtle and the mechanism so well hidden (that's provided if you can reach this point) that I don't think I would have figured them out without the instructions. With the last move, the shackle suddenly springs springs open...and there you go, the T9 is solved! Resetting the T9 is surprisingly easy, given the many steps previously....just turn the key!

Once you know the moves, sequence and what to look out for, repeat solving is quite manageable and can be done reasonably quickly, within a couple of minutes even.

With the exception of the T7 and T8, Rainer Popp has made a return to the traditional Popplock style of puzzle locks with the T9. Those who have played with the earlier versions from T2 to T6 would know what I mean. Puzzle/trick locks don't show up very often, in fact since the T8 in 2013, the only other metal puzzle lock at this level of quality and manufacture that came to the market is the Swing Lock from Splinter Justus (which I do not own). 

Very difficult yes, but overall the T9 is an excellent puzzle lock with multiple stages and steps to keep one well occupied with progress and a-ha moments along the way. Expensive also yes, but lots of puzzling value for money. The workings of the lock (from the internal diagrams in the manual) have to be seen to be believed.

As far as I can tell, unfortunately there are no T9s available commercially at the moment as all appear to have gone to private hands. Not surprising, since Rainer produces very limited units for each new model, just anywhere between fifty to less than a hundred.

[Edit 8 January 2015 - I have just been informed by Wil Strijbos that he still has one last copy of the T9 available for sale at 380 euros. If anyone is keen, please PM me via my blog email and I will put you in touch with Wil]

Lock 250 / Schloss 250

Update 23 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

Name
Lock 250 / Schloss 250

Designer
Jean-Claude Constantin, one of the most prolific puzzle designers around. Too see his work, click here.

Manufacturer
Jean Claude Constantin. Available from Mr Puzzle of Australia, Sloyd of Finland and PuzzleMaster of Canada. My copy (together with some other puzzles) came from Sloyd, great service and very reasonable shipping rates.

Type & Classification
Puzzle lock. But also a puzzle within the category of "n-ary" puzzles. For more on "n-ary" puzzles, you can read puzzle collector Goetz Schwandtner's article here. For a super humongous lock that requires over 340 million moves, you can read Allard's post about the Generation Lock. 

Dimensions
9.9cm (Width) x 14.7cm (Height) and 3.2cm (Depth). A relatively large puzzle.

Materials & Construction
Plywood layers laser cut and glued together, with external veneer. Steel screws and sliders. Construction fit and finish is very good overall. However, the sliders don't slide as smoothly as they should when the internal wooden plates have moved into certain positions. Some moves ok, some not. Slight jamming occasionally, but nothing serious.

Overview
Not the usual trick lock in the traditional sense but rather a "n-ary" puzzle shaped like a giant pad-lock.

Object is to open the shackle and to do this, all the 4 sliders must be moved left and right to end up all on the left side. It takes 250 moves to open and hence a further 250 to close. Does take a while to just open the lock. The bottom slider is the main one that facilitates the moving of the other 3 sliders above it.

If you get the moves correct, its more an exercise in repetitive moves which eventually leads to the release of the shackle. But wrong moves can set you back a bit and you have to repeat any number of steps from 2 to 20.

I made some wrong moves and took longer than really necessary to solve this one.

Difficulty Level

Not difficult once you get going and discover the pattern of how the sliders operate, although the repetition may cause some very tired fingers. But the anticipation of solving does build up gradually as you see the topmost slider moving slowly towards the left, which signals the end is (finally) near.

Summary
The Lock 250 is a nice and different take on both the trick/puzzle lock as well as the n-ary puzzle. Great concept except my own copy has been let down a bit by the execution; ie the less than efficient sliding mechanism which make for some rather tiring (and frustrating) puzzling.

Popplock T8

Update 26 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

Name
Popplock T8

Designer
Rainer Popp, who is perhaps the undisputed master of trick/puzzle lock design. Since his first lock the T1, Rainer has come up with a new puzzle lock virtually every year.

For all my reviews of Popplocks from T2 to T7 in this blog, please click below:-
1. T2
2. T3
3. T4
4. T5
5. T6
6. T7

Manufacturer
Rainer Popp. Unfortunately no longer available from the usual online retailers such as Puzzlemaster and Grand Illusions. May be available from Rainer direct or possibly Wil Strijbos.

Type & Classification
Trick/puzzle lock.

Dimensions
14cm (Length) x 3cm (Width) and 8.5cm (Height). Very heavy!

Materials & Construction
Lock body and shackle are both made of stainless steel, with some brass bits. In the tradition of Popplocks, supreme quality and manufacture with a very high price to match.

Overview

After the somewhat less than positive (and in some quarters very critical) reaction to the earlier T7 by puzzlers, many of whom had felt let down by the puzzling experience, I think Rainer has been able to regain and dominate the high ground in puzzle lock design with the T8.

The T7 is water under the bridge. As far as I can tell, every puzzler that I have been in contact with, and from what I can glean from the Internet, Facebook, puzzle forums etc, the T8 appears to be getting a standing ovation. Hence the quick sell-out by puzzle retailers, notwithstanding the very high price tag.

The T8 breaks away from the traditional "padlock look" and instead adopts a contemporary, clean and very modern styling I am add. At first glance, the uninitiated may not even think its a lock. The T8 has a stainless steel body, as opposed to the usual brass. This is only the second time Rainer has chosen to use steel; the first being the limited edition T2 (or T2VA).

The shackle runs through the cylindrical lock body which at one end sticks out a brass knob with a protruding red dot. The other end is engraved with Rainer's Popplock logo. The T8 comes without a key, so obviously it is intended that you can open the lock without one.

Rainer usually has a number of tricks up his sleeve when it comes to the Popplocks so I was trying to use all my experience with the previous six Popplocks to figure out what possible mechanism might there be which is holding the shackle in place. The T8 took me a long time; over several days of intermittent puzzling before I came upon the solution. And even here, it was not a case of logical deduction or analysis but more through trial and error (read "random trying this and that").

In the end, after I had unshackled the T8, I could only marvel at the ingenuity of the design. The solution is really so simple and elegant; but of course only after having figured it out and with hindsight.

Difficulty Level
Very difficult when you are struggling to find out the solution. Most puzzlers are stuck after the first one or two steps. Some very experienced puzzlers have taken days to solve.  But simple to execute once you know how to. Very easy (and fun) repeatable solving.

From Left: T2, T3, T4, T5, T6, T7 & T8
Only the T3, T7 & T8 do not have keys or key holes

Summary

The T8 scores top marks in my book not only for quality and design (very unique and unusual mechanism/trick), but also for the puzzling experience. Expensive but well worth it. As I mentioned in a Facebook post, I think from a practical standpoint given the way the T8 is solved, it can also actually be used like a real lock, tho' I doubt if anyone would!

Lunatic Lock

Name
Lunatic Lock

Designer
Gary Foshee

Manufacturer
My copy was bought from Ebay, a real steal at around US$5/- plus, if my memory is correct. According to the packaging, it was made by Puzzle Makers International, Taiwan. Currently available from several online retailers including Bits & Pieces, PuzzleMaster and Serious Puzzles.

Type & Classification
Trick/Puzzle Lock

Dimensions
7.5cm (Height) x 5.7cm (Width) x 1.2cm (Thickness).

Materials & Construction
Brushed aluminium for the lock body and steel for the shackle. Overall quality is slightly above average (for my copy) but everything works properly. Sure, it's not a Popplock..... but hey its also at least fifteen times cheaper!

References
See http://www.puzzle-place.com/wiki/Gary_Foshee. There are at least six puzzle blog reviews on the Lunatic Lock. See also http://www.puzzle-place.com/wiki/Lunatic_Lock

Overview
I must be one of the last bloggers to play with and review the Lunatic Lock. I have had this lock for some time now and only recently discovered it at the back of my puzzle closet.

This trick lock comes without a key nor a keyhole, but has a bolt sticking out underneath the shackle. So the only way to solve it would obviously have something to do with this particular bolt. Took me about half an hour or so of fiddling to figure out the solution.

If you compare it with the Popplock range, the internal mechanism can be considered relatively simple. But because it is hidden (unlike the Popplocks which is more sequential discovery oriented), it makes the solve a little bit more tricky. Nimble fingers and a soft touch would certainly help here.

Difficulty Level
While not a difficult puzzle lock, nonetheless it is no walk in the park by any means either and the beginner/casual puzzler would face some degree of challenge.

Summary
If you are not sure about whether you are going to like trick/puzzle locks, the Lunatic Lock is a very good introduction to the puzzle lock genre. Inexpensive and pain free to try before plonking down serious cash for the (much) more up-scale and very expensive Popplocks.

Popplock T7

If you thought that Rainer Popp's puzzle locks could not get any bigger than the humongous T5, think again! Weighing in at a massive 1.1kg, Rainer's latest creation, the T7 is a behemoth. Measuring 12.6cm high, 6.4wide and 3cm thick, its taller and 200 grams heavier than the T5. The T7 has a rather unique octagonal cross-sectional shape with a steel button on one of the sides and a round knurled knob at the base of the lock.

The lock body is milled from a solid block of brass while the shackle is stainless steel. Like the rest of the Popplock family, build quality, fit and finish is first class. Once the lock is opened, you will also discover that the attention to detail in the construction of the inside is really incredible. From an aesthetic standpoint, both externally and internally, this is probably one of the most beautifully and intricately made puzzle locks I have come across.

From a puzzling perspective, I found the T7 much easier compared to its earlier cousins. I managed to release the shackle within minutes rather than hours. The solution to unlocking the lock has to do with manipulating the knurled knob at the bottom. Puzzlers who are familiar with the Revomaze would know exactly what I am talking about.

An additional feature, which I thought was rather clever and a real plus is that the T7 can be modified to make the solution varying degrees harder. The T7 comes equipped with all that is necessary for the owner to make it as easy or as hard to solve as he/she chooses. Oli has dealt with this much more extensively in his review of the T7 so I will not duplicate the details here. As always, Popplocks are not cheap, and the T7 is no exception.

The T7 is quite a radical departure from the earlier Popplocks. All the earlier models I have played with; the T2, T3, T4, T5 and T6 have one or more clever "tricks" involved. The T7 I felt, unfortunately lacked the typical Popplock surprises one has come to expect.

A number of puzzlers in the community also felt let down by the T7, especially given the very expensive price tag that it came with. However, I would like to mention that these puzzlers probably have been saturated and "spoilt" by the Revomaze and hence understandably consider the T7 not up to standard. My humble opinion is that if there were no Revomaze in existence today, I am pretty confident that the T7 would likely have been considered by many as one of Rainer's best creations. Despite the seemingly unavoidable T7-Revomaze comparison, I think most puzzlers would agree that the solution to the T7 (or any puzzle lock for that matter) is quite imaginative and unexpected.

Personally I have only one criticism of the T7, and that is perhaps Rainer could have made the lock a much harder solve to begin with; then at least there would have been a fair amount of challenge expected from a typical Popplock, never mind the lack of trick(s). Aside from this and notwithstanding the less than positive comments from some quarters, I still consider the T7 to rank up there with the rest of its brethren. Expensive? Yes. Worth the money? Yes. Collectible? Definitely.

Danlock Model B

Update 23 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

Every puzzle review that I have come across on the Danlock has praised it. I have always wondered what was so special about it, after all, the lock looks like any another padlock. From an aesthetic point of view, it certainly does not have the Popplock-style embellishments nor the typical over-the-top dimensions.

It was only several weeks ago that I received the Model B from it's designer Dan Feldman. I waited for nearly 9 months as it was out of stock then. 

The lock itself looks pretty ordinary. Dan had chosen to use a stock lock made by the Nabob company in Israel for his puzzle. The lock measures about 8.5cm tall and 5 cm wide. It is larger than a Popplock T6, but smaller than all the other Popplocks in terms of size and weight. It has the usual brass body but instead of steel, the shackle is also brass. As a real functioning lock, the quality is very good and looks well capable of deterring break-ins.

The "trademark" of the Danlock which makes it recognizable is the broken key that comes with the lock. The object of the puzzle is not just to unlock the shackle but to relock it with everything back to their original place. Dan states in the puzzle instructions that everything that is needed to solve the lock is present; the ring that hold the two pieces of the broken key is not needed, neither is the draw-string pouch that accompanies the puzzle. In a way, the Danlock could be classified as a sequential discovery puzzle.

Unlocking the lock is easy part. When you look at the pieces you have, it is obvious that the broken key shard has to be used somehow. Using the broken key, I happily unlocked the lock in a jiffy. The real (and very difficult) challenge is to restore the lock back to its original state, with both the unbroken key and broken key attached back to the shackle. 

I was stumped for a number of days at this stage; trying different things but with no success. Finally I contacted fellow puzzle blogger Kevin Sadler for a clue. He gave me a hint and I re-examined carefully everything I had in front of me again; the lock body, shackle and the 2 keys. I decided to experiment with some moves I hadn't tried previously nor thought of. Lo and behold, my efforts were rewarded not too long after that. I managed to reinstate the Danlock to its original state. Certain aspects of the solution is very well disguised and the action steps required to completely solve the puzzle were quite surprising and totally unexpected. 

I feel it's by far the best and perhaps one of the most difficult trick locks I have come across. The only other lock that I would consider which can give the Danlock a run for the money is perhaps the Popplock T4. The real appeal of the Danlock lies in its ability to hide a really amazing mechanical puzzle design within the confines of an ordinary and non-script looking padlock. And unlike most other trick locks, here, both the opening and closing are part of the solving process.

Not cheap but the Danlock is good value-for-money given it's puzzling aspect. Definitely worth acquiring. The Model B is available directly from Dan Feldman.

IPP32 Exchange Puzzle From Wil Strijbos

Update 26 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

Wil Strijbos calls his Exchange Puzzle at IPP32 the "Exchange Washington DC". A bit of a mouthful here so I will just term it "The Exchange".

Wil's Exchange can be classified as an "Impossible Object". One look at the puzzle and you can see why. The Exchange is made up of a 60 ml urine sample container, within which there is a lock with key inserted, both suspended at the end of a red plastic rod that runs through the container's cap. Residing at the bottom of the container is a steel ball bearing. The bottom of the container has a cut-out hole, but not large enough for the ball bearing to pass through.

At the top end of the red rod is a screwed-in loop which hangs another key and a rectangular-shaped ring. A rubber bung helps to hold the rod in place and prevents any unnecessary sliding down. The cap has an unbroken seal so you probably wonder how Wil had managed to squeeze the lock and the other contents into the container.

The object of the Exchange is to remove the ball bearing and have the final puzzle looking exactly like the "Solution Picture" (see above photo). There is an additional challenge which is shown on the reverse of the photo below-to get the rectangular ring over the shackle of the lock inside the container.

Solving impossible objects requires logical thinking and a systematic approach. For this one, a fair amount of dexterity is also required. I discarded my usual trial and error method and actually spent some time analysing how to extract the ball bearing.

There are twelve steps to solving the puzzle as intended, at least according to my count. Without giving too much away, firstly there is no need to use force; the laws of physics cannot be defied. Secondly, do not attempt to break the seal and unscrew the cap (I don't think Wil intended it to be solved this way). Lastly, everything you need to solve the puzzle is there and no external tools are required. You just need to think creatively how to use what's been given (in a way, you can think of this like a sequential discovery type puzzle)....and if you happen to have nimble figures, this would certainly help as well.

This is my first impossible object from Wil (who has produced a number of Coke and other bottle creations in the past). I found the Exchange very enjoyable and while the removal of the ball bearing itself is not too difficult, it is the getting everything back into position that is more challenging. For a while I was caught off guard; the way forward for the last two steps was right in front of me...yet I just didn't see it.

What I like about the Exchange is that you can see everything that you are doing - no hidden this or that. Definitely worth getting  for both the fun factor and puzzling aspect. As of this post, I am still puzzling over the second challenge which seems to be a real tough cookie!

Popplock T4

Update 23 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

The word is out that Rainer Popp's T7 puzzle lock will be available sometime very soon. Hence for the last week or so, I have been labouring over the T4, hoping to solve it and round off my reviews for the Popplock series before the T7 makes it first appearance. The T4 is really one serious tough cookie of a puzzle lock...but more onto that later.

Clockwise from left: T3, T2, T5, T4 and T6

The T4 is Rainer's 4th puzzle lock in his famous Popplock series. I obtained this lock last year courtesy of Wil Strijbos who happened to have one last piece left. As far as I can tell, the T4s are all in private hands and not commercially available anywhere. For reviews of the rest of the Popplock range (except the T1), you can check out my earlier posts for the T2, T3, T5, and T6, all pictured above.

T4 with Rainer Popp's Signature Cat Face Logo

Physically the T4 is a large and very heavy lock, maybe not as large as the T5, the latter which is humongous but certainly its body is much thicker than the T2, T3 and T6 at nearly 5cm in depth. Overall height and width is about 8.7cm by 6cm. The body is uniformly round and symmetrically shaped on both sides front and back. The lock is milled from a single solid block of brass and the shackle is stainless steel. As with all of Rainer's locks, the quality of construction, fit and finish is really excellent and all moving parts are manufactured to incredible tolerances. In front of the lock is Rainer's signature "cat face" logo. The T4 comes with a steel key but on first inspection there appears no key hole anywhere to be found for a key to be inserted....strange!

There are 5 steps to opening the T4 according to Rainer. Well, depending on how you count each step, Steps 1 and 2 are relatively easy and pretty obvious. I managed them in several seconds. However the next couple of steps stumped me...and I made no progress whatsoever for quite some time. No amount of shaking, tapping, tugging etc helped. My fingers were numb and hands tired. I had very much expected the T4 to be difficult and especially Step 3 to be the major obstacle after having read the experiences of puzzle bloggers Oli, Brian, Jeff and Jonas with the T4; but I did not imagine it would be that difficult!  It came to a point where I decided that I really needed a hint to move forward as I was getting nowhere after Steps 1 and 2.

Oli came to my rescue and after an exchange of emails over several days, I managed to overcome Step 3. Step 3 is so well disguised that I would not have been able to solve it on my own. A big thanks to Oli for giving me only one tiny hint at a time so as not to spoil my fun (or frustration) in solving the T4. Step 4 was easy, no sweat. But then it was Step 5 that got me stuck in my tracks again. Again, very tricky! Thankfully this time round, through some trial and error, I achieved Step 5 much more quickly and with that, I finally pulled the shackle out of the lock...whew!!

As I mentioned in my earlier posts on the Popplock series, the T4 is generally considered the hardest in the range from T2-T6. I am really glad I left it to the last, otherwise it would be been pretty discouraging for me if I had started with the T4 before the rest. I personally think that the T4 is so much harder than the next most difficult lock in line, the T6. On hindsight, the T5, which came out after the T4, seems comparatively easy. It was the T6 which brought the difficulty quotient back up a couple of notches. 

Now the wait for me and other puzzle lock lovers is the T7. From what I gather, the T7 will really be huge; I don't mean the physical size...as I have not even seen it yet, but it would be huge in terms of challenge (and in all likelihood, the price as well!). Stay tuned!

Bowling Alley In A Briefcase

I managed to snag this Bowling Alley In A Briefcase puzzle during the recent Jacques Haubrich Puzzle Auction for quite a reasonable price (well, reasonable in so far as dedicated puzzle auctions generally go). Designed by Kathleen Malcolmson and made by Norman Sandfield, this was their IPP26 exchange puzzle in 2006 in Boston.

Some time back, I had already come across Malcolmson's and Sandfield's three briefcase puzzles while searching for their availability on the internet; the Double Locked Briefcase Puzzle for IPP24 in Toyko, the Bollixed Briefcase Puzzle which was an entry in the IPP25 2005 Puzzle Design Competition in Helsinki and this one, the Bowling Alley Briefcase. I had also come across an online photo (Warning: Spoiler Alert) of an opened Bowling Alley Briefcase, so roughly I had an inkling how the puzzle worked. Notwithstanding, these puzzles were not available anywhere then (nor even now) and when this Bowling Alley Briefcase came up in the Haubrich auction, I grabbed the chance to go for it.


I would say this is a rather unique puzzle because most puzzle designers and makers create something from scratch or ground up using various materials such as aluminium, plastic or wood but instead, Kathleen Malcolmson has taken an existing item, an aluminium briefcase business cardholder (which is available commercially online) and turned it into a puzzle. In my view, this may be perhaps a harder way to produce a puzzle, since the designer/maker has to work within the constraints and restrictions of an existing object. 


First off, the puzzle is a good size for the palm, measuring 9.9cm x 6.7cm x 1.6cm. Made of aluminium, it is a cute briefcase in miniature form, complete with a handle and working lock latches. The object of course is to open the briefcase and here, clear instructions on the lid state that "no major force is required". I would imagine the designer thought this was necessary to prevent undue damage through the unintended forcing open of the lid by either over-enthusiastic or inexperienced puzzlers. Quality of my copy is very good and the briefcase looks almost brand new with no blemishes or marks.

The first step was easy - I undid the lock latches which sprung open, but the lid remained tightly shut. Mind you I had already seen a photo and know what the inside of the briefcase looks like. The lid is kept shut via an internal mechanism which has to be unlocked. But even having seen the internals, it still took a bit of time for me to figure out how to solve the locking mechanism properly. The solution is actually quite simple and elegant and one can only be impressed at the ingenuity of the design. The difficulty lies in not being able to see what is happening inside the briefcase. 


The Bowling Alley Briefcase is similar to the genre of puzzles such as Remove The Yoke, Brass Treasure Chest and Centrale where there is a hidden mechanism inside the puzzle that can only be solved via a number of sequential steps taken in the right order. If you have read my reviews of those puzzles, you will realise I didn't have any luck with any of those. Without any aid, I think this is really a difficult puzzle and I don't think I would have been able to solve it on my own. Brian Pletcher in his review of the same puzzle said he too scratched his head over it for quite a long time before finally solving it. 


Overall, a rather unusual, unique and challenging puzzle, very hard to come by and I am glad I managed to get hold of one. Too bad it can't hold any of my business cards tho'