Neil's Puzzle Building Blog
5Feb/134

Revomaze Clear Sleeve – Followup

This entry is part 7 of 11 in the series Revomaze

A little while back I wrote about the process of turning a clear sleeve for the Revomaze puzzles, however I hadn't really completed the project at that time. I didn't have springs, and I was still trying to figure out how to put a spring in there so that I could complete the project and have a fully working sleeve. I've now finished the process, found springs, a way to put them in the sleeve, and have a set of fully working sleeves. Read on to find out the end of the story...

The Finished Sleeve - Photo courtesy of Allard

The Finished Sleeve - Photo courtesy of Allard

Thanks to Allard for the excellent image above. For more of his thoughts and a clear perspective, go have a look at his blog.

Before going off and making many more of the sleeves, I had to make sure that it was possible to make it into a working puzzle. That meant I had to solve the issue of the spring. From the Revomaze website, there is a pin and spring kit listed in case you managed to lose the set from your puzzle. Sadly they were showing out of stock and to be fair, it was a fairly expensive route to take, given that I only needed the spring. I decided to contact Chris Pitt, to see if he could help, or at least help out with dimensions of the spring and also how deep the spring hole is drilled into the sleeve. Sadly I never did receive a response back from Chris, so I had to look at alternate avenues.

Fortunately, a good friend had a spare spring or two and offered to measure it for me so that I could try to find a replacement. He even went so far as to measure the length compressed, and of course managed to have the tiny thing launch itself from the calipers and get lost in the carpet.

Top to bottom:  Threaded plug, my spring, official spring, official pin.

Top to bottom: Threaded plug, my spring, official spring, official pin.

It turns out that the spring measurements are: Outer diameter 2.90mm, Length 5.98mm and Compressed length 3.9mm. It really is tiny, and therein lies a problem. It's a completely custom size. I spent a lot of time hunting online spring makers to get an exact match (and that's without knowing the compression load) and just couldn't find one. I did finally get something that's very close and decided to settle on it, but even then it wasn't cheap. To buy just one of these is $7 each! The price drops as you order in bulk, but still not a cheap part.

As you can see from the photo above, the spring I found is slightly thinner in terms of the wire thickness, but pretty close in the other dimensions. The 1 euro coin should give you a feel for just how small these are.

A week later the spring arrived, and I was a step closer to a working maze. I still had the issue to work out the drill depth for the spring/pin hole. While I had been waiting there was some talk on the Revomaze forums about how to do this, and Thayneq suggested having the pin/spring being removable. Well I went off and experimented with a tap to be able to thread the outer sleeve, and put a screw plug in there. Turns out that a 6-32 tap is too small for the pin, and a 8-32 is too large. In the end though this worked to my advantage. The pin itself is 2.90mm wide, so I was able to drill a hole all the way through one side of the sleeve for the pin, then drill 3.7mm using the larger drill bit to take an 8-32 thread and plug.

This actually solves three problems. Obviously the pin is now removable, so if anything goes wrong when you're solving a maze, just remove the pin. Secondly, I've not had to drill all the way through the sleeve from the other side and then plug the hole. This is the way the official sleeves are made, and the plugged hole is then covered with the Revomaze sticker. As you know I'm not affiliated with Revomaze in any way, and don't have stickers, so the 'plug' was just going to be an eyesore. I'm also pretty sure that I don't have a long enough drill bit to get all the way through either, so that was a nice bonus. Finally, the screw plug allows the tension of the spring to be adjusted so that the movement in the maze 'feels right'.

Note: The Image below is deliberately dark to ensure that no solution details for the maze are given away.

The plug covering the spring without giving anything away of the maze solution.

The plug covering the spring without giving anything away of the maze solution.

With all the pieces in place, I had to take the plunge and try it on one of my test sleeves. I put the ridged sleeve I had in the vice, carefully drilled it, and then re-drilled for the plug. Taking the pin from my blue maze, popping that in the hole, followed by the spring and then the plug I was able to check the compression of the spring, and compare that to the depth the pin sat on the official sleeve. After some fine adjustment of the screw until I was happy, I took the pin back out; assembled the blue core and inserted it into the sleeve.

Having now sent a few of these out, my friend with the spare spring has tried both the official spring, and the one I found, and prefers mine because the spring compresses a little more meaning that the plug can be screwed in a little further. He's also done some other testing, but I'll come back to that later.

After a little jiggle the pin dropped into the hole, and I was able to turn the maze and reset it. That familiar click left me with a huge grin on my face, and of course this time I could see exactly what had happened. The question now was whether the maze was solvable!

Very cautiously, I started to navigate the maze. Of course I'm now holding the puzzle 'upside down' and looking at the pin rather than the sticker. Despite working with the ridged sleeve, and there being a fair bit of distortion along the length of the maze, the section under the pin is perfectly visible, and it's easy to navigate. At the first trap, I fall off, and hear that familiar click. Somehow it seems even more satisfying being able to see the pin fall off! After a couple of tries, I make it through the maze, past the tricky section with ease, and the pin easily drops back into the core, and I can remove it from the sleeve. IT WORKS!

As with anything in science, doing it once isn't good enough, it has to be repeatable, so after picking the pins up from the floor (Ed: You'd think with the number of these I've solved I'd not drop the pins by now) I re-assembled the core and put it back in again. Playing around I tried moving to various parts in the maze, and dropping into a reset and restarting; each time grinning because I was controlling the click. Having navigated to the end again, I tried to remove the pin, and found it didn't want to come out. Puzzled I tried the usual tapping and jiggling, but it wasn't dropping. Of course I could see the pin and couldn't work out what was stopping it. No worry though I unscrewed the plug, and removed the pin that way ...

... Then realised what an idiot I'd been. Rather than turning the puzzle 'upside down' so that the pin fell into the core, I'd been trying to get it to drop into the sleeve hole. Just shows how being able to see what you're doing doesn't always help!

So with the proof of concept working, I took a quick video to show the operation and sent that to a couple of close friends. Now I had to start making these as the requests were coming in pretty quickly!

Some of the production sleeves, with a much clearer view

Some of the production sleeves, with a much clearer view

Something which had bothered be about the initial two sleeves I'd made was the 'bubbles' which are visible on the inside of the sleeve. This occurs due to the high temperature created by the friction when drilling out the core, but I wanted to try to reduce that and get as close to a clear, unobstructed sleeve as I could. With a little bit of work, and some liquid cooling for the drill bit I think you'll agree I succeeded, and the sleeves are now much clearer. Just look at that shot at the top of this post from Allard. His images really show off how clear the sleeve is, and I have a good few more from him that I just can't show as they give huge hints to the solution of the revomaze shown.

Using the saw as a staging area for production

Using the saw as a staging area for production

As you can see, production is now underway. Given that these are all hand turned, and finished, it still takes a good few hours per sleeve, but from the feedback I've had from the people who have one, they're pretty happy, and that makes me pretty happy too.

One thing to point out is that the tolerances on my core are slightly larger than those from the official source. Nothing in the Revomaze design is standard sizes. The core is custom, the sleeve is custom, the spring is custom, the pin is custom, and as such you can't buy tools which match the dimensions. As such I have had to make things as close as possible, but close is not exact. Having played with some of the mazes, Silver, Lime and Handmade as specific examples, there are elements in these mazes which do not work exactly as expected due to the larger gaps in the internal sleeve dimension. It is possible to solve these mazes, but some extra care is required, and some parts of the solution become trickier than with the official sleeve. I do know that Blue, Green, Bronze, Black, Orange, Gold, Red all work with no issues and really look quite stunning when displayed in these sleeves.

There is one further extension that I am looking at. I had a request for transparent colour matched sleeves for each maze. That requires custom casting of coloured acrylic, so for now it's further away from reality. I do have paint based pens which are designed for working on acrylic and may add colour bands to the sleeves so you can see which maze is in a sleeve from a distance, but that's still to come.

Hope you've enjoyed the look at the project, and keep an eye out for a time lapse video of the process coming soon...



29Mar/130

Making a Clear Revomaze Sleeve Video

This entry is part 8 of 11 in the series Revomaze

So in case you're not subscribed to my You Tube channel, in which case you'd have missed this, I created a video showing the process of making one of the clear Revomaze Sleeves. Since I'm not taking any more orders, and will be shipping out the last of the orders I do have fairly soon, I thought you might like to see exactly what goes into making one of these, rather than just the pictures I posted in the past.

Hope you enjoy!

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30Dec/124

Revomaze Sleeve Project

This entry is part 9 of 11 in the series Revomaze

As many of you know, I've owned and solved all of the Revomaze Series One puzzles released, including the Gold puzzle, which I'll write about soon. For a long time on the Revomaze Forums, a clear sleeve which would allow you to see the maze as you solved it has been talked about and many people have asked for one. Well having added the lathe to my list of tools, I thought I'd have a shot at making one.

Since getting the lathe, I've made a few pens, some bowls, all just learning how to use the tools, and get the shapes I want made. I mostly work with wood, as that's where my real love is, however I have played with a few acrylics as well. I find the acrylic to be a pain to work with, since it tends to create thin streamers of plastic which just wrap around whatever you're working on, and obscures your view of the work. Still, there's no way I could make a clear sleeve from wood.

Clear sleeve starting point.  A 2

Clear sleeve starting point. A 2"x2"x8" block of Acrylic.

It all starts with a block of clear acrylic. This piece is 2"x2"x8", which will be enough to make two sleeves. I got it from Tap Plastics here in the bay area. They'll custom cut sheets while you wait, and their prices are pretty good. I'm no expert with the plastics, but I can certainly recommend them.

The block turned to a cylinder.

The block turned to a cylinder.

First up, I need to take this perfectly clear block, and make a complete mess of it; otherwise known as turning it round. Doing that removes the beautiful clear finish, and turns the whole thing a rather cloudy opaque grey colour. When I'm working with Acrylics, I need to wear my respirator, as the smell created when working it tends to give me a headache. Not bad practice anyway, but something I have found I have to do. As it turns out, I'm also somewhat allergic to the material too. When I'd finished turning the block into a cylinder, and brushed all the tiny shavings off my arms, I found that I'd reacted rather badly to it. Time for a shower and some anti-histamine!

The initial shape of the sleeve

The initial shape of the sleeve

Having cleaned up, and put on long sleeves, I came back and shaped the outer surface of what would become the sleeve. Using the sleeve from my bronze maze as a template I matched the dimensions as closely as possible, including the ridges along the main body of the sleeve, and of course, making sure that the length was exact, since the intent is to make a fully functioning sleeve.

At this point, I've kept the sleeve attached to the main piece of perspex as I still need to drill out the central hole where the shaft will be. Before I go and drill that out though, I want to get the clear finish back so that I can see what I'm doing when drilling things.

Outer surface sanded to 12000 grit.

Outer surface sanded to 12000 grit.

After around half an hour of work, I end up with the finish above. This is wet sanded all the way up to 12000 grit to give a finish close to how the block arrived.

Ready to start drilling

Ready to start drilling

With that done, and the cylinder being transparent again it's time to change our the tail stock on the lathe for a 15/16" forstner bit to drill out the hole in the sleeve. Given the length of the hole I was drilling, the drill bit alone wasn't going to be long enough to make the cut. I had bought a bit extender so that I'd be able to drill the length I needed.

Starting to drill

Starting to drill

Ribbons of acrylic as the drill bit cores the sleeve

Ribbons of acrylic as the drill bit cores the sleeve

As you can see, with a sharp bit, the cut creates long streamers at the beginning of the cut, but before long, the heat almost melts the acrylic, and you have to be careful to eject the shavings before they solidify behind the head of the drill bit, and make it impossible to remove the drill bit.

'Bubbles' on the inside as the drill cuts

'Bubbles' on the inside as the drill cuts

The internal reflections are stunning

The internal reflections are stunning

Even though the drill leaves a rough surface on the inside of the sleeve, given the work sanding it earlier, it looks really good. Once the entire core is drilled out, it will be sanded up to 12000 grit the same as the outside, before being polished to a high shine.

The Finished Sleeve

The Finished Sleeve

Having completed the drilling of the core, I parted off the sleeve, and finished sanding the ends to get the same finish as the rest of the sleeve, things are just about ready. Some plastic polish is applied, and then a coat of Ren Wax to really finish the shine. As you can see, the inner core isn't perfect, but with more sanding I could get things back to a perfect finish. In fact I've gone back and made a second sleeve without the ridges which is far clearer than this sleeve.

A comparison with the original sleeve

A comparison with the original sleeve

Both clear versions side by side.

Both clear versions side by side.


So the real test is left. Can you see the core? Well the answer is a resounding yes. The core is easily visible in the sleeve, and everything fits perfectly. I'm pretty happy with the results.

The Sleeve with a maze in it

The Sleeve with a maze in it



26Feb/143

Revomaze R2 – Mercury

This entry is part 10 of 11 in the series Revomaze

If you've read my posts on the Revomaze puzzles, you'll know the first generation of puzzles ended with the release and solving of the Gold Puzzle. There are a few special editions out there, but for me solving the Gold, was the end of the journey on the R1 puzzles. Chris Pitt, has come out with an entirely new design of puzzle, a second generation of Revomaze puzzles, the R2's. The first in the series is Mercury.

Revomaze R2 - Mercury

Revomaze R2 - Mercury

This second series is based on the planets in the solar system, and the closest to the Sun, Mercury, is the first to be released. The series has had a difficult birth, with the company trying to raise funds to buy CNC machines to bring all the production in-house, and move away from the reliance on engineering companies to produce the limited run puzzles they wanted. To that end, "Voyager Status" was created. This was an up front payment to guarantee the price of each puzzle in the series (up to 10 puzzles) for early adopters. For that you'd receive a limited edition coin (stored inside the puzzle of course), your puzzle would be part of the initial limited edition run of 100 puzzles and would be engraved with a serial number to set it apart from other general release puzzles to be released later.

So back on the 12th March 2013, I sent Revomaze £50 of my hard-earned cash, and sealed myself a place on the voyage to the R2. At some point over the course of the next 8 months there were a few changes to what Voyager status meant, and a decision was made at Revo HQ to limit the R2 run to only the 100 puzzles from the Voyager sign-up. The result of this decision is that the puzzles would only be made to meet the Voyager demand (100 max) and no more would be produced or sold until the Voyager members have ALL of their puzzles from the entire series. So at this point, if you missed out on Voyager status, expect it to be 3 years before you get your hands on a Mercury, or any other puzzle in the series. Note that this assumes a release schedule of 3 puzzles per year.

Not long after the Voyager announcements, the option was given to the first 20 people who wanted to pay for the puzzle to receive the puzzle ahead of the main batch, and be part of a 'Beta Trial' to allow Chris to sort any issues, and make sure the puzzle worked perfectly. Since I'm always happy to help bringing a new puzzle to life, I agreed to be one of the first batch. On the 1st May 2013, I paid for my puzzle, and began the wait for the R2.

Mercury #24

Mercury #24

Background covered, I should probably start talking about the puzzle, as I'm sure that's why you're here. I received my puzzle on the 14th February 2014 and eagerly opened the package when I got home from work, to start playing with the new puzzle. My plan was to take it to the California Puzzle Party on the 15th, and let people play with it there. In fact Chris had express shipped the puzzle to me to ensure that I had it for the Puzzle Party. (Note: He'd done the same for a puzzler on the East coast, and also to some of the puzzlers in the Midlands) Before taking it to the party though I wanted to have some time to play and understand the puzzle. Foolishly, I'd hoped that I could open it before the party. I spent 2-3 hours with it on the 14th trying to understand what was going on, and start mapping out the paths inside the new maze. Most of that was just spent getting used to how different this puzzle is to the original series. It's a completely different animal that needs a very different touch to be able to solve it. And yes, I did take my wife out for dinner that night... I'm a romantic at heart.

The raw maze before it's finished

The raw maze before it's finished

The puzzle itself is made from a couple of solid blocks of aluminium and measures 4-1/8" in diameter by 1" tall. Including the knob for the draw bar the puzzle is 4-5/8" and weighs in at 800g. Now I'll be honest, despite being heavier than the original R1's, the puzzle feels lighter. Perhaps just the weight being spread over a larger diameter helps.

Unlike the R1 where the pin was in the sleeve, and the maze on the central core (or draw bar if you like) requiring you to twist, push and pull the core to navigate the maze, the R2 is a little different. The pin is attached to the draw bar, and the maze is etched onto the titanium coloured disk which rotates inside the black outer case. To navigate the maze you need to both push and pull the draw bar while simultaneously rotating the disk. This requires a lot more coordination than the original maze, and is a very different experience. Any skills you may have learned from solving an R1, will be of little use to you here.

Despite my best efforts and a very crude map, I certainly didn't solve Mercury before the Saturday puzzle party. One issue which did arise as I played with it was that the silky smooth rotation that the puzzle exhibited on the Friday night, wasn't quite as smooth by the time I arrived at the puzzle party. I wish I'd realised before going as the puzzle was mostly unusable given the amount of friction between the maze plate and the case. We required two hands on the disk to turn it in any direction, and really any chance of playing with the puzzle or solving it were gone.

Talking with Chris, he suggested WD-40 would help. Skeptical as I was, I took the can of WD-40 to the puzzle, giving it a good coating, and spin it did. The friction issues were completely resolved, and it moved better than it had when it arrived. Over the course of the next week, I didn't have a great deal of time to spend with the puzzle, but I dabbled on and off mapping as I could and trying to understand what I was 'seeing'.

Mercury during solving

Mercury during solving

Mapping the R2 is a completely different challenge to an R1. With the R1, you can think of unrolling the maze to a flat plane (since effectively that's what it is - wrapped onto a cylinder) but the R2 is already flat, and is circular. Some Polar graph paper may be useful here. Fortunately, the centre of the disk has 24 notches, and the dimples on the outer rim match to 15 degree increments. Handy for reference! I started out with regular graph paper making a very crude attempt with a compass. Let's just say it wasn't elegant, but it worked. A couple of people pointed me to that wonderful invention - the Internet - to download some polar paper, and I transferred things to there.

One thing you'll find in Mercury is that it's full of curves. Actually it's full of circles! Chris claims that the design of the maze is meant to represent the cratered appearance of the planet itself, and I guess I can see that. As I mapped, I found that there was a chunk of the map which I couldn't get to , just a little clockwise of the serial number, and part around 10pm. Now knowing that nothing would be wasted in here, I knew that's where I had to get to, but finding how was proving challenging. The other very concerning aspect I discovered was a trail leading through ~25% of the maze, where everything I had was trap. This was starting to look a lot like a Green. And I hate Green.

After a good few hours trying to find how to get to these new areas, find it I did, and my fears were confirmed. The puzzle becomes a serious dexterity challenge, needing the lightest of touches, and an excellent map. To get there, is a challenging section that I am sure will cause a lot of frustration (it did for me), assuming you can find it. The entrance is very challenging to find, and needs some very careful exploration of the maze.

Given that I have one of the first copies, there's a few issues in the puzzle which Chris is already solving, as quickly as they are identified.

  • The Spring is a little light, meaning that it's possible (and even easy) to hug the walls a little tight, and as a result get to parts of the maze through a route which was not intended. That's fixed with a stronger spring in the draw bar.
  • There is a slight amount of play in the draw bar, meaning that it can rotate a fraction while you're solving. It's not a problem that affects the maze, and it certainly won't help you, but that will be tightened up in the later releases.
  • The last and biggest issue with the early release is that the pin has a fairly rounded profile as you'll see in the photo below. That means that in some areas where there are ledges in the puzzle, the pin won't stay on the ledge, without applying some pressure to the wall. That's being fixed with a different profile for the pin head.

As a result of these issues, a number of people have managed to open the maze very quickly having taken a path which was not intended. I didn't find these shorter paths, and completed the maze as intended. The benefit of having produced this short run is that Chris is learning how the puzzle is used by someone who doesn't know what's going on inside, and by the time these get into general production for the remaining 80 in the run, they will all be perfect. It was a very sensible decision by Chris, and one which I hope he is aware was the best way to launch a new design, and make sure it's exactly the way he intended.

Mercury #24 - Open

Mercury #24 - Open

From start to finish it took me around 8.5 hours to open the Mercury, and I'll be honest, it's a challenging puzzle, not for the faint of heart. It's difficult from start to finish, and darn right evil from 50% through to the end. I'd even go so far as to say that the very last few millimeters of the puzzle are Satan incarnate. This is perhaps one of the most challenging static puzzle that Chris has released to date, and to my mind is far too challenging for the first puzzle in the series. Yes, you can argue that it took me less than 10 hours to open it, so it can't be that difficult, considering how long it took me to open Silver from the R1 series, however I go back and re-solve Bronze and Silver. I never go back to Green, and I'm unlikely to want to ever go back and re-solve Mercury.


As a small aside, when the puzzle was opened, I found some small flakes of metal sitting in the case of the puzzle. Presumably from the grinding as a result of the friction between the two large plates of aluminium. It doesn't affect the puzzle, and I certainly don't see any damage to the maze, but clearly there is some wear as a result of using the puzzle.

Metal shavings in the case

Metal shavings in the case



11Jun/151

Revomaze Copper

This entry is part 11 of 11 in the series Revomaze

It's been quite a while since I've sat down and written anything on my blog, and I'm sure many of my readers had given up on me. I am still here, I'm still puzzling, and still making more new puzzles, so nothing has really changed. Life sometimes just gets busy, and the time to sit down and write something worthy of reading is the thing that slips through the cracks first. That said, today I'm looking at the newest puzzle to come from Revomaze, which they kindly sent me a copy to review for you. This is the Copper V1 puzzle.

The Revomaze R1 Copper

The Revomaze R1 Copper

The newer puzzles coming from Revo HQ are showing up in these nice new boxes, which give the puzzle a little extra padding during transit, and leave you with a good looking box to keep the puzzle in when you're not solving it or displaying it somewhere else. There's still a little work needs to be done on the box to prevent the core from taking a knock during transit but this is a good step forward from the old fish net and plastic bag wrapping we had seen. Much more fitting of a puzzle in this price range, and quality.

New Boxes

New Boxes

As with all the Revo puzzles I've had in the past, the initial look and feel is great. These are still high quality puzzles, made with an attention to detail. The Copper, like it's predecessors weighs in around the 600g mark and certainly put a strain on my hands again.

It had been over a year since I'd worked on a Revo R1, and the familiar sore hands and fingers were back. It's recommended to work on the puzzle in short sessions, and I can't agree more. If you've not played with one for a while, your hands are going to thank you for taking a break. Fortunately there are convenient spots in the puzzle where you can put it down and not lose progress.

The Copper is a move back to the original static maze style, such as the Blue and Green puzzles, which I and many other puzzlers really enjoyed. There's no moving sliders, or free floating ball bearings in this puzzle to confuse and confound you. Just a traditional maze, with Chris' own devilish traps and pitfalls to navigate. That said it's not all old and familiar stuff in here. There's been a couple of modifications to the pin that are going to catch the unwary puzzler, so be warned, this isn't simple by any measure.

As a regular reader you'll know I own (almost) all the available Revomaze puzzles, and have successfully opened all of them with varying solve times from a few months to a few days. They're all challenging puzzles, and all for different reasons. I enjoy the puzzles that either make me think or are just enjoyable to solve. Bronze still ranks as my favourite in the series, with Blue being a close second. The reason for those choices comes down to two things. Bronze was a significant challenge to understand the dynamic features, but wasn't so difficult to be frustrating. Blue is just a really fun puzzle. While initially difficult to understand what was going on, once you understood the principles of the puzzle, it was both repeatable, and enjoyable to solve. Now add to that the Revo Mini which is a tiny scaled version of the blue maze, and there's a lot of positives from those two designs.

The Copper claims to "Triple the fun", and I'll agree to some extent with that statement. The internals are unlike any of the static mazes to have come before, and there's certainly more in there. As far as the fun, the initial part of the puzzle contains one of my least favourite features in a hidden maze puzzle. The dreaded bridge.

Much like the Green, the bridge frustrated me more than provided fun, and Copper has that same frustration level for me. Don't take that as a negative on the puzzle as a whole, just that it's not one of my favourite challenges. The dexterity sections can be overly difficult and if you fail near the end, restarting can be quite off-putting. That said, the satisfaction when you complete it is certainly well earned.

Personalised Serial 'Number'

Personalised Serial 'Number'

Given that Chris now has many of the machines in house, personalised engraving is possible as you can see from the serial number on my puzzle. I certainly didn't request this, and it was great to have this reveal as I started working on the puzzle.

One thing of note, at least for me is the strength of the spring in the copy I have. I'm not sure if this is across the board or not, but I feel that the movement of the puzzle is quite "stiff". The power of the spring along with the modifications to the pin made the navigation more challenging than I remember. There's a lot packed into this puzzle, and with sore fingers I found it quite the task to keep making progress in a single session. Taking regular breaks is the only way to get through this one. I don't think we'll see anyone doing speed runs to get the fasted solve time in the near future. I think most will be happy to solve the puzzle, and see the work that went into the core when they're done.

If you're on the fence about getting a Copper, and want a serious challenge, without the worry of ball bearings running awry, or dynamic devices to confound, then go ahead and pick one up. There's a lot to like about this puzzle.