Concentric Arc

You would have probably guessed that this is another Robrecht Louage design. The Concentric Arc, exchanged by David Pullen at IPP37 in Paris last year.

http://mechanical-puzzles.com/concentric-arc/

Naked (Coloured) Maze

This "new" design of mine is not really new....at least not the concept. There are a number of similar puzzles incorporating see-through maze channels, including some interesting ones like the Cubus, the Boston Subway and The Lunatic Revealed.

I wanted to try my hand at designing a hidden maze and I also know a guy who can do laser cutting and familiar with the puzzles (packing ones) that he has been churning out for me. It was also an opportunity to try out Burr Tools for this design...a puzzle with only ONE moving piece.

Basically the Naked Maze consists of 3 layers of 10mm thick acrylic (plexiglass) that is glued together and these 3 are sandwiched by a 3mm top and 3mm bottom translucent coloured layer. Each of the 3 main layers have maze channels cut into it and the combination of the 3 layers results in both horizontal and vertical channels throughout the "box".

The maze has a number of twists and turns and in this first prototype, there are about 12 dead-ends. The object is to pass a ball bearing through the hole in the green layer, navigate and exit the ball from the hole in the orange layer. For this puzzle, I used a 9.5mm ball bearing that is heavy enough and fits very nicely inside the channels.

Because I used transparent acrylic, you can actually see the ball from the side of the puzzle as well as through the top and bottom coloured translucent layers. However, while you can see the ball, the channels are not that easy to determine and the dead-ends make the puzzle a tad harder. For a really difficult puzzle, the maze can be constructed of all black (opaque) acrylic and there would be no way to see the channels and/or the ball, making it a really "blind" maze in every sense of the word.

I know how the channels run (cos I designed them) so it wasn't difficult for me to navigate the ball to the exit rather quickly. I am curious to see how another puzzler or non-puzzler would perform, so this coming weekend, I will try it on some unsuspecting friends and also ask award-winning puzzle designer Goh Pit Khiam to have a go at it when we next catch up. My next prototype will be a 4 layer maze which should make it even more challenging, particularly if its a blacked-out totally blind one.

And did I mention its really cool to see the solve on Burr Tools...as you watch a little cube (representing the ball bearing), going in one hole and out the exit, racing through the channels using the shortest route possible!

8 Stars Labyrinth

Name
8 Stars Labyrinth

Designer
Robrecht Louage. The 8SL was also Robrecht's entry to the IPP35 Puzzle Design Competition.

Manufacturer & Availability
Manufactured and sold by Robrecht himself. He may still have some copies available. 

Type & Classification
Route finding/Maze

Dimensions
12cm x 8cm x 2.5cm

Materials & Construction
The puzzle is made of Trespa (a very strong and durable composite laminate made of resin reinforced by cellulose fibres generally used for interior table tops) with a translucent covering made of frosted acrylic. Construction, fit and finish is superb with very tight tolerances and everything accurately cut (especially the maze channels). A very high quality and solid puzzle.

Overview

Robrecht Louage is very well known for his "remove the coin" puzzles such as his 1 € Labyrinth and Remove The Yolk. And of course who can forget his IPP31 award winning 4 Steps Visible Lock. Then he has designed several of the more typical maze style puzzles like the Larva and La Cerradura Doble. 

The 8SL seems to be a bit of a departure from both of these styles. Instead what we have here is a puzzle which requires you to navigate a little ball bearing (7.5mm diameter) through a series of channels fraught with a number of traps and obstacles along the way. 

Object is to put the ball bearing in the hole "IN" and get the ball through the maze and its obstacles and then exit the hole marked "OUT". Take a look at the photo and you will know what I mean.

Difficulty Level
The 8SL is a bit beyond moderate difficulty. Quite a number of traps along the way. While some of the obstacles are visible through the translucent cover and its obvious what needs to be done, some are not and requires a bit of trial and error. And in some cases, dexterity is required. There are also four traps that are hidden from view (the blacked out areas on the cover) and these require some thinking as to how to pass the ball through them. 

I had previously designed a couple of puzzles involving moving ball bearings (see my BIC#1 and BIC#2) and so had some inkling of how the traps might work. But despite this, I still took nearly 45 minutes to solve the puzzle. Gabriel Fernandez took just 10 minutes! I guess I spent the most time on the bottom hidden maze. Its almost right next to the finish point but because its hidden and the ball is only visible through some of the holes at the bottom plate, I made a number of unsuccessful attempts before getting the ball back out to the top channel.

Summary

Overall a nice, fun and more than sufficiently challenging puzzle; not the most difficult by any means of course. And at times, you have to navigate blind. But a great concept in puzzle design, no less. What I like about the 8SL is that you get the "a-ha" moments as you successfully tackle each trap/obstacle. You can feel your progress and can take your time to finish the solve in stages.

A Coffin Puzzle

Nope...this is not a puzzle from a super famous designer of the same name we all know so well. 

But this puzzle (a.k.a Escape The Plague, ETP) is actually the design of and IPP34 Exchange Puzzle from Kate Jones, who runs Gamepuzzles, a US online retailer of games and puzzles, the latter which are also all designed in-house.

If there was a prize at IPP34 for packaging, ETP would surely have won hands down for originality. ETP is a "maze connection" puzzle where the first challenge is to form a single "escape route", by placing the 16 square tiles within a square formed by the 4 side strips and navigating from the start point (red dot) to the exit gate (round dot). The second challenge is the arrange the tiles to form separate loops. 

ETP was designed around the theme of The Great Plague Of London, a major epidemic which killed hundreds of thousands of people in England during 1665-1666.

In "deathly" fashion and true to its theme, the laser cut tiles and strips are packaged in a miniature wooden coffin; which is probably just large enough to contain a small (dead) rat. The puzzle even comes with a sheet containing instructions and the history of The Great Plague.

The puzzle has more than one solution and the total number of solutions are not known. Kate is offering a nice prize to the first puzzler that can offer proof of the number of solutions. Well, I wasn't gunning for Kate's prize but merely content to find at least one solution. And I did! While not very difficult, it's no walk in the park either. There are 16 possible positions for the tiles and each tile has 4 different orientations. The side strips forming the square have 6 possible arrangements. To top it off, the route has to run through each of the 16 tiles as well as along all the 4 strips in a single continuous direction with no doubling back or crossing paths. It took me a while to figure out the entire route and I encountered several dead ends along the way before finally reaching the exit. 

ETP is limited to 125 copies, so there may still be some left. If anyone is interested, you may contact Kate via Gamepuzzles.

Simultaneous Maze

This is another interesting design from William Hu. Called the Simultaneous Maze, the object is to extract a maze plate from the box frame, while manipulating the three vertically sliding square pieces.

Made by Eric Fuller from Maple, Jatoba and acrylic, construction fit and finish is excellent and all moving pieces slide smoothly. Aesthetically, it really is a very pleasing looking puzzle with a nice colour combo and contrast. The choice of acrylic for the maze plate is a good one, since I doubt wood would have been able to take the stresses of play over time, given the way the channels in the maze are cut. However, I did detect some flexing even though the plate is 5mm thick. I think a 7-8mm thickness would have been a better choice. Let's put it this way...you can't be too rough with this one.

The puzzle provides a fair amount of challenge and while not unduly difficult in terms of what needs to be done, it is however, rather tricky. I found myself stuck a bit at the early stages until I discovered something which I had overlooked at the beginning. This is one of those puzzles that to move two steps forward, you may need to take one step backwards, in a manner of speaking. Once solved, the resetting is in the reverse, but still, unless you have memorized all the moves, it will still take some effort (and trial and error, which happened to me) to insert the maze plate back into position.

Larva

The Larva (and Ladybird which featured at IPP34 in London this August) are the latest designs from Belgian designer Robrecht Louage. 

Robrecht is very well known in the puzzling community for his "remove-the-coin" and hidden maze/route finding puzzles. 

Amongst his designs are the La Cerradura Doble, 1 Euro Labyrinth, Remove The Yolk and Escape From Alcatraz. Robrecht's most famous design; the 4 Steps Visible Lock was also the winner of the Grand Jury prize at the IPP31 Nob Yoshigahara Puzzle Design Competition in Berlin in 2011.

Object is to remove a Euro 50 cent coin through a cut-out in the upper cover. While the previous remove-the-coin puzzles involved a hidden maze, the Larva's consist of navigating two metal sliders through two visible and movable maze plates. The Larva appears to be a new design take.....a "cross" between the La Cerradura Doble and 1 Euro Labyrinth.

The puzzle is made of Trespa and acrylic and is very well made. Everything is precisely machined cut to very tight tolerances and fit and finish is excellent. The Larva name and worm etchings add to the fine detailing.

From a puzzling standpoint, it is not an overly difficult puzzle for more experienced puzzlers, especially those who have played with Robrecht's previous works. But it is no walk in the park either. One of the challenges is to figure out how the two maze plates interact with each other and which direction either is suppose to go in order for the coin to be freed.

Personally I found it a bit more difficult than La Cerradura Doble. However because you can see what you are doing and can chart your progress as you go along, you feel the urge to continue to the end and not put it down; just the sort of puzzle to occupy you for a good half to one hour on a lazy Saturday afternoon, with an end in sight and not too much stress. The Larva is fun and very manageable.

For those of you who may not be aware, the Larva and Ladybird puzzles is a collaboration between Robrecht and puzzle collector Michel van Ipenburg. If anyone is interested in acquiring any one of these puzzles, please PM me via my blog email and I will link you up with the aforementioned gentlemen.

Pentomino Maze

Name
Pentomino Maze

Designer
Tamas Vanyo. A very prolific designer with numerous designs to-date. Click here to see his latest designs.

Manufacturer
Pelikan. Currently available from PuzzleMaster.

Type & Classification
Interlocking, sequential movement

Dimensions
10cm (Length) x 6cm (Width) and 3cm (Height). 

Materials & Construction
The frame is Maple while the pieces are Mahogany. As usual, very well made and everything fits and slides together smoothly and nicely.

Overview

This is my third puzzle from Tamas, the previous two being the Orsi and Noncsi reviewed a while back.

Pentominoes have a place in my heart. My first five wooden puzzle designs were based on Pentominoes. Aside from this, I also tend to like non-cube shaped puzzles.

Unlike my amateurishly designed puzzles, Tamas' sophisticated version here consist of an irregular shaped maze frame to which the pieces, consisting of 12 pairs of pentominoes (connected together) must be inserted in to form a rectangular solid box.

As the name implies, the puzzle is indeed like a maze and you need to "navigate" the pieces through a single opening of the frame. Be careful here though as the frame can be rather delicate since its only connected at two places and excessive force may result in breakage.

Removing the pieces is relatively simple since its just a matter of sliding the first piece out and the rest will follow suit. 

Re-assembly (everything in reverse) is far more difficult if you mix up the pieces, their orientation or forget the order they come out. My suggestion is that you photo document your disassembly moves. Trying to first find the rectangular shape of the box with the pieces away from the frame probably won't help much since there are 2339 ways to form a 6 x 10 rectangle using all the 12 pentominoes. Tamas didn't make it easy for this one. But rest assured, there are no rotations needed here.

Difficulty Level

Easy to take apart but very difficult to put together (if you happen to choose to scramble up the pieces and lose your way). But help is at hand for those lost via either Burr Tools or www.puzzlewillbeplayed.com.

Summary
A different take on a very nice interlocking puzzle with a Pentominoes theme, fully utilising all 12 flat pentomino shapes.

1 € Labyrinth Puzzle

Name
1 € Labyrinth Puzzle

Designer
Robrecht Louage.

Manufacturer
Robrecht Louage. Puzzle directly available from him via his email found on IPP32 site. Priced at 20€ but it's really only 19€ because you get 1€ back from the puzzle...if you manage to get it out that is.

Type & Classification
Maze; Route Finding.

Dimensions
18.6cm (Length) x 7cm (Width) x 1.5cm (Thick)

Materials & Construction
Trespa (a very strong and durable composite laminate made of resin reinforced by cellulose fibres generally used for interior table tops), transparent acrylic, steel ball bearing and screws. Like all of Robrecht's previous puzzles, quality, fit and finish here is very good. Looking through the clear acrylic panel, the maze inside appears to be very nicely and finely cut by laser. The choice of materials used is in my opinion very suitable for this type of puzzle; in terms of quality and durability versus affordability.

IPP
The 1€ Labyrinth Puzzle was a competition entry in the IPP32 Nob Yoshigahara Puzzle Design Competition in Washington, USA, 9-12 August 2012. Robrecht's 4 Step Visible Lock won the Jury Grand Prize at IPP31 in Berlin the previous year.

Overview
This puzzle came to me courtesy of Robrecht and is his 4th puzzle in my collection. The other three are the 4 Steps Visible Lock, Remove The Yoke and La Cerradura Doble all which I have reviewed previously in this blog.

In some ways similar to the 4 Steps Visible Lock, the object is to extract the 1€ coin from puzzle. To achieve this, you have to move the acrylic panel left and right by navigating a ball bearing through a maze inside. I found the 1€ Labyrinth much harder and trickier to solve. It took me nearly an hour whereas the 4 Steps Visible Lock was solved under fifteen minutes. The added difficulty was the fact that the maze is only partially visible and sometimes you will lose sight of the ball bearing.

Difficulty Level
Challenging and tricky but not unduly difficult. Those who have solved the 4 Steps Visible Lock would probably find it easier as there is a similar step involved.

Summary
Overall, a puzzle that is fun to solve and one which can be solved repeatedly (and quickly) once you know the trick/mechanism involved. For a rather well made puzzle, it is also very reasonable priced and value for money. The puzzle will make a nice addition to any collection. But the 4 Steps Visible Lock still remains my top favourite of the four puzzles mentioned.

Boston Subway

The Boston Subway was super-prolific puzzle designer Oskar Van Deventer's IPP26 Exchange Puzzle. My guess is that the design and name of the puzzle was in keeping with the theme of the host city of IPP26, Boston, USA in 2006. The Subway was designed by Oskar but made by George Miller. I won this puzzle recently in an auction held on www.puzzleparadise.ca.

The Subway is a very cute pocket-sized maze puzzle, which was what attracted my attention in the first place. Measuring a very handy 9cm x 7.5cm x 1.5cm, it is made up of five layers of clear acrylic joined together. Atop the puzzle is a little red "rod" or magnetic wand which is used (from the outside) to navigate a very tiny magnetic disc inside the maze from the start point to the end point, from HOME to WORK and back HOME.

This is a 3-dimensional maze consisting of an array of both vertical and horizontal paths as well as side-way channels, no curves, but just like a real city subway system with all its levels, walkways and lifts. Although my copy came to me second-hand, the quality of construction and finish is very good.

This puzzle is very challenging since the clear layers of acrylic make it very hard to see the various paths, channels and openings clearly (no pun intended) and the disc being so small. For me, it was quite a bit of strain on the eyes. I fiddled with the puzzle for a pretty long time, dragging the disc all over the maze with the wand, trying to reach my destination but got nowhere.

The fact that the disc sometimes just froze at some of intersections of the the channels and openings didn't help either. Was it electrical static that caused the disc to get stuck now and again? I am not sure. In the end, I solved it by referring to the solution. I later discovered that playing with the maze in front of a computer screen in a dimly lit room showed up the maze's paths very much more clearly!

I asked Oskar why a magnetic disc was chosen (given the kind of difficulty I faced) instead of perhaps using a small ball bearing, which to me seems a better choice. Oskar replied that his original version was to use a ball bearing but implementing the disc was George's idea. Anyhow it was felt that the disc involved less dexterity and more control with the wand. Well, who am I to argue with Oskar anyway?

Not easy to solve given the maze design and materials used and also the requirement of the wand to move the disc around. I wish I could pry open the acrylic layers and replace the disc with a ball bearing but that would mean an irreversibly damaged puzzle.  Nevertheless a uniquely themed maze and certainly a rare and collectible puzzle.

RevoLUTION Ball Puzzle

This is my 100th post!!!

How time flies since my first post over a year and a half ago. For this post, I have decided (instead of the usual puzzle review) to showcase a puzzle of my own creation; something that I designed myself.

This puzzle of mine is inspired by the genre of the hidden maze puzzle, the latter which usually consist of a blind maze, the object of which is to navigate a marble or ball bearing from a start point to an end point.  Examples of such puzzles are the Lost Marble Puzzle and Magic Dice. The most famous of all the hidden maze puzzles in recent years is of course none other than the Revomaze.

Externally my puzzle appears to resemble a Revomaze Silver Extreme. It is approximately 10.5cm long and slightly over 3.5cm in diameter. It is made of aluminium and steel. But here’s where any similarity ends. Unlike the Revomaze series which all have extremely difficult to solve and intricate hidden maze designs, my little project is rather simple and very amateurish. 

I managed to source aluminium cheaply from a local supplier and by good fortune, a metal fabricator willing to produce a single unit of my puzzle at a very reasonable price.

The puzzle consists of 6 circular discs, each approximately 1.2cm thick and stacked together to form a cylinder shape. The discs are held together with an extended steel screw rod running through the discs and secured at the other end by two nuts. 

The object of the puzzle is to navigate a 6mm ball bearing from a side hole in the topmost disc, through each of the stacked discs and out through a similar side hole at the bottom disc. The discs are able to rotate freely and to navigate the ball bearing, you turn each disc to allow the ball bearing to pass through, from one to the next. Each of the discs has a hole drilled through and the trick is to align the holes to form a “passage” for the ball bearing to pass. 

Dexterity is required here since you will need to rotate the discs to feel (and hear) the ball bearing drop from one disc to the next. To make the puzzle much harder, I drilled some “blind” holes on each of the disc, so that if the ball bearing falls into a blind hole, you will need to turn the puzzle upside down to let the ball bearing fall out to re-start again. This has actually made the puzzle a lot more difficult than necessary as I can testify to.

This is my first puzzle design project and I am quite happy I managed at least to get a prototype unit produced that actually works.

I have just finished a second puzzle design and its now in the hands of my fabricator friend. This puzzle involves a ball bearing inside a cylinder that needs to be removed (and no, it’s nothing like Wil Strijbos’ Aluminium Cylinder Box or Washer Cylinder; I am not even remotely close to such genius).

Many thanks to Erhan Cubukcuoglu of Puzzlehan for his comments and advice on puzzle making and hidden mazes.

Update (19 January 2013) - My second puzzle design, which I call the Ball In Cylinder Puzzle, has been produced. Details can be found HERE.

Cubus

The Cubus is a 3-dimensional labyrinth puzzle designed by Jeremy Goode and available from Xmatrix. This is the smaller of the 2 sizes available; the larger version called the Quadrus. Although described as pocket size, I doubt if anyone can fit a Cubus which measures about 2 3/4 inches square, comfortably into a shirt or trouser pocket. More likely it can fit into a jacket or coat pocket or handbag.

The Cubus that I acquired is the "blue" version which has the 3D maze made out of a bluish colour transparent acrylic (or as some would call it perspex). The maze itself looks highly complicated and is housed within a clear acrylic cube.  Both the Quadrus and Cubus also come in a light yellow version. The Cubus was shortlisted Gift Of The Year 2010 and although this may come as a surprise to many, it was also entered for the recent 2011 IPP Puzzle Design Competition, even though both the Cubus and Quadrus have been on sale for quite some time already. Someone on the Revomaze forum commented that as long as a puzzle is designed within 2 years of the competition date, that puzzle would still be eligible to enter, which therefore explains why.

I find the construction of the Cubus to be first rate. All the 6 sides forming the cube are neatly fused together and there are no rough edges or corners of any sort. Overall quality is very good and the Cubus feels solid in the hand. Do note though that acrylic can scratch easily so be careful about the surface you place a Cubus or Quadrus on...I know this because I use to own acrylic fish tanks!

The object of the puzzle is to navigate a small ball bearing from the silver coloured top frame to the bottom gold coloured frame through the 3D maze and then back again. In the first photo above, the silver frame is shown as the top. Unless you are in some kind of a speed competition, it doesn't really matter whether you start from silver to gold or vice-versa; the point is to use gravity (and dexterity) to get the ball bearing to travel through the 3D maze from top to bottom.

I took about 35mins just to complete one direction, albeit at a very leisurely pace while watching TV. The Xmatrix site claims that it is possible to complete both directions in 4 minutes.  I suppose there must have been some  capable individual(s) who can achieve this kind of record time. While challenging enough for a serious puzzler, I think where the Cubus can really shine is as a coffee table or executive puzzle; where just about anyone (puzzler or not, adult or kid) can pick it up, admire its see-through 3D maze, have a play with it and then put it down.

Straight Forward

The Straight Forward from Mr Puzzle Australia was a participating entrant in the 2008 IPP Puzzle Design Competition. Designed by Brian Young, it is a maze type puzzle consisting of a rectangular block of wood with a centre trough or "dug-out" drain stretching from one end to the other, over which is covered by a sheet of perspex (acrylic). Although physically its simple and innocent looking enough, the way to solve this puzzle is anything but simple nor straight forward (no pun intended). The puzzle is made of Queensland Blackbean wood and part of Mr Puzzle's "craftsman range of superior wooden puzzles". Judging by the workmanship and finish of my piece, the Straight Forward is indeed a high quality item.

The puzzle itself measures about 6 3/4 inches long, 2 inches wide and 3/4 inch thick. The aim of the puzzle is to move the ball bearing from the "Start" position at one end of the puzzle to the "Finish" position at the opposite end. Getting in the way of the ball bearing moving from end to end are three tiny metal (brass I think) pegs that slide in and out from holes on either side of the trough or drain. Depending on how you tilt the puzzle, at any one time at least one or two of the three pegs will slide out of their own holes and "block" the ball bearing in its path, hence making it seemingly impossible to move it to the "Finish" position as intended.

I spent several hours on this puzzle but could not get the ball bearing to reach its destination. I decided then to look at the solution, which really surprised me. I would say that the way to solve this puzzle is actually quite clever in a certain sense, in that the solution was really not what I had expected in a puzzle of this nature. But then again, its the unexpected twist I think, that makes a puzzle unique and interesting. The way this puzzle is solved reminds me of the often quoted saying; "sometimes the easiest way is the obvious way". But then again, the obvious way is not always as obvious as it seems. Although Mr Puzzle rates it as level 7 (out of 10) in difficulty, I would say the puzzle more likely deserves an 8.

Blind Labyrint 1A & 1C

It has been mentioned more than once on the internet that the Blind Labyrint (no, its not misspelled) is the grandfather of the Revomaze. I could not agree more with this statement. The Blind Labyrint series of puzzles were designed in the early 1980s by Lauri Kaira. According to Sloyd where I acquired both puzzles, only about 2000 units were made. Sloyd informs me that there are actually only two puzzles in the series, graded 1A and 1C (there is no 1B in between), the 1C as being difficult. Both 1A and 1C are still available and Sloyd has categorised them as collectors' puzzles.

The puzzle is entirely made of aluminium, comprising two main parts, the maze portion and the sleeve portion. The maze is "inscribed" (if this is the appropriate word to use) onto a burnished aluminium tube. The maze does not run the entire length of the tube but rather ends just somewhere before the halfway point. I suppose if the maze did run the entire length, the puzzle would undoubtedly be a lot harder than it is. At the other end of the aluminium tube, a short section of the black sleeve is attached permanently.  The second part is the sleeve portion which is entirely in black and holds a small (steel) pin used to navigate the maze. When the puzzle is solved, both parts form nicely into a single black tube. The puzzle is 3 1/2 inches long and has an external tube diameter of 1 3/8 inches.

The puzzle components are overall well made and of high quality. Fit and finish is generally good.....subject to one caveat which I shall elaborate below.

The object of the puzzle is of course to navigate the maze with the pin attached to the black sleeve, and to move the sleeve to cover entirely the burnished aluminium tube. 1A is a one-directional maze meaning that there is only one entry point for the pin. The pin will follow a single twisting path towards the end. Version 1C which is the hardest has two entry points and the maze is an "open" design, with a various paths to the final solved stage but fraught with numerous dead ends.

Blind Labyrint 1A & 1C in the foreground

Being somewhat ambitious, I started with 1C first. I managed to surprise myself when I was able to navigate the pin from start to finish rather quickly, at most 15 minutes I think. Feeling rather smug that I had solved it so quickly and wondering if the puzzle truly deserved its 1C rating, I started to backtrack, ie to navigate the maze backwards and remove the sleeve from the tube. Here is where I had to swallow my ego and pride after over an hour of struggling....I somehow could not seem to find my way back out! No matter what I tried, I keep getting myself into a dead end and had to find my way back to the starting point to start over again...(sounds familiar with the reset in the Revomaze?).

In the process of trying to disassemble the puzzle, at one point I got both the tube and sleeve jammed pretty badly and had to use a certain amount of force to free both parts. While doing so, I heard certain sickening crunching noises as metal rubbed against metal, much like scratching your nails on a blackboard. Thankfully after several attempts over a couple nights, I finally managed to dislodge the sleeve from the maze tube.

Here is where the downside of the puzzle shows itself. Unlike the Removmaze, the pin on the sleeve is not spring loaded. The maze itself also has relatively sharp edges at the bends. As a result moving the pin through the maze is not as smooth or easy as one would have liked. In fact you will hear rough grinding noises from time to time as you twist and turn. Perhaps the tolerances may be too tight, which results in a lack of sufficient "free-play" of the pin within the paths of the maze. One must avoid using any force or the pin will jam as I had experienced. An almost gentle delicate touch is required to push, pull or twist the sleeve through the maze tube to avoid getting stuck and possibly damaging the maze . Handled carefully, the puzzle was problem-free.

Notwithstanding the above, one must remember that this series of puzzles is 30 years old! They were made at  a time when technology was not as advanced, unlike today's modern puzzles like the Revomaze which have the benefit of computerised and precision manufacturing techniques.