Popplock T6

In January this year, I had reviewed the Popplock T3 and Popplock T5 in this blog. While sufficiently challenging, both the T3 and T5 were the two easiest of the Popplock series to solve. This is not to say they are easy; not at all, but easier than the rest. With the T6, the difficulty quotient seems to have gone up several notches. It took me a couple of weeks over a number of sessions before I managed to "crack" it open.

Measuring a diminutive 5cm x 4cm x 1.5cm in the locked position, the T6 is the smallest in the Popplock series and also the most affordable. The T6 is made of 4 layers of steel held together by rivets (here owners have a choice of copper or aluminium) to form the lock body. I chose the copper rivet version as I felt a contrast of colours gave the lock more character and uniqueness. The twin shackles are also formed from two thick layers of steel. All this is probably necessary to keep the cost down. The rest of the series from T1 to T5 is milled from a single block of brass (with the exception of the Limited Edition all-steel T2). While the T6 is a fraction of what it's larger siblings cost, there is no lacking in quality.

In the usual Rainer Popp style, the construction, fit and finish of the T6 is excellent. Despite its small size, the T6 still feels relatively hefty in the hand and probably serves its function as a normal lock just as well as a non-puzzle lock of similar dimensions.

Depending on how you count, there are a total of 5 or 6 steps to opening the lock. To those who are still struggling with the T6, the rivets do not play a part in the solving, neither does just simply inserting the key into the keyhole and trying to unlock it in the usual way. To solve it, you must turn the key in a certain way and in different directions. However, this will only get you to about the second last step of the solution. There is one final step which must be executed before the shackles can be released. This final step is totally unexpected for a puzzle of this nature. It really came as a real surprise to me when I eventually discovered it after my longish struggle with the T6. A very clever and usual mechanism indeed! Hint: there is a clue left by Rainer to give some indication how the shackles might be released but you have to study the T6 carefully.

Overall, a very challenging puzzle lock with a surprising twist at the end. If this is any indication of the increasing level of difficulty of the next two locks in the series I am going to attempt, ie the T2 and T4, well, I would have to hunker down for a long and arduous battle ahead....stay tuned for my review of the T2 after I have solved it!

Four other puzzlers have reviewed and given their thumbs up to this tiny lock which packs a quite a wallop. Do check out Neil's, Oli's, Allard's and Kevin's blogs for their take on it.

Popplock T4

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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!

Popplock T3

Happy New Year everyone! My first post for the new year will feature the Popplock T3 which actually has been around for some time already, since 2009. I obtained the T3 from lock collector Peter Friedhelm von Knorre. The T3 is part of a series of six puzzle locks (T1 to T6) designed and manufactured by Rainer Popp of Germany. Having so far acquired the entire series from T2 to T6 (except the ultra/super rare T1, of which I am informed by Rainer that there are only 30 in existence), I was wondering which lock would be best to start my Popplock adventure with. Prudence and good sense suggested that I should start with the easiest and work my way towards the hardest. Having read the reviews of Allard, Oli, Brian, Jeff and Jonas and after checking with Oli, it seemed that the T3 was the easiest of the lot that I should begin with.

While not physically the largest lock in the series, The T3 is in fact the second smallest after the T6. Construction, fit and finish of the T3 is really excellent. Dimensionally the T3 is 10.3cm tall, 5.4cm wide and about 2.2cm thick and it is really hefty in the hand. A real quality product, which accounts for the rather high cost. The lock body is milled from a solid block of brass and the shackle is steel. In the middle of the T3 is a circular disc which is actually a knurled dial (not shown in the photo, but visible from the other side of the body) that runs through the centre of the lock. The face of the dial is engraved with the Popplock logo. This dial can turn both clockwise and anti-clockwise as well as be depressed into the brass body. The shackle runs through the body and protrudes out the bottom end by over 2cm. Unlike the other Popplocks, the T3 does not come with a key and there is also no key hole.

The objective of the T3 is of course to unlock the shackle. There are 4 steps to opening and unlocking the T3; well...depending on how you choose to count each step. These consist of, amongst other things, manipulating and twisting the dial. I took about 2.5 hours of on-off puzzling to solve the T3. Once you discover the solution, it is really simple to repeat solving the T3. You can literally do it in under 10 seconds! The mechanism involved appears to be deceptively simple, but because the lock is so well crafted, the final key (no pun intended) to solving the T3 is really very tricky and clever and unexpected. This step is certainly not easily discoverable, to say the least. I was really quite surprised at the way the T3 is solved.

Overall, I felt quite satisfied that I had solved this puzzle with minimal frustration and without resorting to the accompanied solution....a nice way to start off the puzzling year! And now, for the next lock up the difficulty scale.... the T5!

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.

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]

Danlock Model B

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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.

Popplock T2

This is my fourth review of the Popplock series of puzzle locks by tricklock maestro Rainer Popp. Earlier in this blog, I had written about, in ascending order of difficulty the T3, T5  and T6. The next one up now is the T2, which is considered as the second hardest after the T4, not counting the very rare and elusive T1.

The T2 is a big lock (although not as massive as the T5) and measures about 10.7cm tall, 5.6cm wide and 2.2cm thick. The body is manufactured out of a solid block of brass and comes with a stainless steel shackle, making it a very heavy puzzle indeed. The lock comes with a key and a little solid rod with a sharp needle-like end. There is also a limited edition numbered version of the T2 made entirely of stainless steel named the T2VA. As with all Rainer Popp's locks, quality, fit and finish of the T2 is excellent. All moving parts are smooth as they should be. But of course such craftsmanship comes at a price and the T2 is very expensive. As of this review, the T2 appears to be only available from Finish online retailer Oy Sloyd Ab. In fact, it is probably the only Popplock left that is still available commercially as far as I can tell. I obtained mine from Wil Strijbos sometime last year; it was one of the few that he had left.

The T2 while resembling a big conventional padlock in almost every way does have some unusual external features consisting of 4 steel screws (which appears that can only be removed with a special Allen key) and six brass circular tabs each with a hole in the centre. Also, the key hole is on the front of the lock instead of the more usual bottom.

According to Rainer Popp, there are six steps required to open the lock and these are sequential. The T2 took me about fifity minutes to an hour to figure out and solve. For me it was my usual method of trying this and that with both the key and rod to see what works...there was really no systematic manner which I went about it since I had no clue as to what the internal mechanism of the lock was like. My previous experience with the T3, T5 and T6 did not help either. The first two steps are pretty easy and obvious. However steps three to six are far more difficult and if you get the sequence wrong, the lock well, remains locked. I was confounded with the steps for a while until I managed to get the hang of it in the right order. Once the T2 is unlocked, the shackle is freed by pulling it out. It does not spring out like a traditional lock. To relock, you have to push the shackle back in place and reverse the steps for unlocking.

While I did mention above that the T2 is second hardest, I actually found the T2 much easier than the T6, the latter which took me a lot longer to solve. Notwithstanding, I think the T2 has more than enough challenge and with its superb build quality, well worth the money and a real collector's puzzle. Four other puzzlers have blogged about the T2; you may wish to check out Oli's, Jeff's, Jonas' and Brian's puzzle blogs. Until Rainer Popp makes available the T7 which I hope will be sometime pretty soon, my next and last review of his lock series will be the T4; which by general consensus is the hardest of the lot...stay tuned!

Popplock T8

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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 T5

After solving the T3 recently, I decided to try my hand on my next puzzle lock, the humongous T5. Although the T5 is the fifth lock in the Popplock series, from what I gather, its the second easiest to solve after the T3.

The T5 is a monster! Measuring a massive 10cm tall, 7cm wide and 4.4 cm thick, it weighs a whopping 900g.  That's about a third more than a Revomaze Extreme, which is considered already very heavy for a puzzle. Your hands get tired quickly while playing with this puzzle lock. The T5 is reminiscent of the old style "bullring" locks. The T5 body is milled out of a solid block of brass while the shackle is made of stainless steel. Quality of the T5 is first class with excellent precision, fit and finish. This puzzle feels super solid and probably can withstand anything short of a nuclear explosion. But such quality comes at a price and the T5 like all the other Popplocks, is very expensive. Notwithstanding, this solid T5 will outlast me and be puzzled over by my descendants from the next couple of generations. About 100 of these locks were produced in 2010 but currently none are commercially available except perhaps through private sales.

There are 4 steps to unlocking the T5 and I easily discovered the first 3. However the last step eluded me for quite a few days. Each time I would get stuck after step No3 and spend a long while pushing, twisting and pulling at the various parts of the T5 in my vain attempts to free the shackle...but with no success. Both Oli and Brian had commented in their blogs that the final step is the most challenging and the key (no pun intended) to unlocking the T5. After being stuck for some time, I suddenly realised that the last step was actually right before my eyes...it was my own perception of how a lock should be opened that had prevented me from solving the T5 much quicker! Indeed the final step is very clever and for me, totally unexpected. Looking back now with hindsight, the T5 is actually a rather fairly simple puzzle lock to solve.

Overall, the T5 is well conceived and an excellent puzzle in all respects (other than the price). As far as I can tell, it is not commercially available from any of the usual online puzzle retailers. So if one does surface from a private sale, just spend the money and don't miss the chance to acquire one!