I would like to present my Open Master Pentultimate. This puzzle, when it is sitting on a desk, seems innocent enough:


VIDEO

And indeed, when you pick it up it looks like this:


So this is my Open Master Pentultimate. It was obviously inspired by the open puzzles of Tony Fisher. However, having the freedom of 3D printing I am not limited by existing puzzles. Tony's Open Petaminx for instance has a Megaminx on the 'inside' but having it there does not really add anything since the Megaminx is also on the outside. My version is a bit like a Multidodecahedron, with a (bandaged) Megaminx on the inside and a (bandaged) Master Pentultimate on the outside. This means the outside can be solved while the inside is still scrambled or vice-versa.
A mayor advantage over my Multidodecahedron is that it is far much easier to see inside.

VIDEO



This puzzle only really has 3 turnable faces. This was achieved by removing the cuts surrounding one corner. An alternative would have been to remove the 5 cuts surrounding a center, which would have essentially resulted in a Pentultimate (with internal parts visible). I decided to stick some gold stickers on the open part since without them it just looked very dark. I think this is nicer.
The puzzle is 40mm on an edge. It's quite large so the puzzle on the inside is also nice and large. The hole is about 60mm in diameter.

Photographing this puzzle was quite hard. Even though it looks really nice in real life and the stickers inside are well visible and vibrant, getting enough light in for the camera was difficult. I took several auto-bracketed shots which I later composed to form the final images (HDR photography). I also used a flashlight to get some light inside. But still, I want to empathize that seeing inside this puzzle is far easier than seeing inside a Multidodecahedron. Check out the video, I think it shows the colors better than the photos I took. What's also weird is that your two eyes play tricks on you, you can see a little more of the puzzle than I can get on a camera which only has a single lens.



The rotational movement on this puzzle is very smooth. I have not used springs in this design as that would have required the inner puzzle to become smaller which would have been a shame. The feeling of this puzzle is therefor a little different from other puzzles which do use springs like my Multidodecahedron but it's still very good.

VIDEO

This puzzle is available as a DIY kit (WSF) for about $205/€195 from Shapeways (I can only see EUR prices so the USD price is an estimate). Due to a recent price change, WSF polished is now a pretty affordable option at only $215/€205. I am also selling assembled copies but the waiting time is currently a little bit longer.

Click here to buy the Open Pentultimate from my Shapeways shop

I love it. The gold stickers work and the coloured insides have a very neat look since they kind of "sit back" more than on mine. Superb.

It's nice to see this finally released. I am glad that you decided to go with 3 turnable faces, rather than 5. I think the hole is very pleasing to the eyes, and is quite big enough (I know that was an original concern).
Great work, as always.

-Doug

WOW!

This looks like a Geode!

WOW, that's amazing Tom. What smooth turning as well! It's awesome how one person can inspire another and how designers can create something that sparks excitement in other designers like this =)

Very nice puzzle. And a very nice packing of the puzzle's pieces...

I'm curious... is the spider core and the ring around the opening all printed as a single piece? I was expecting the above picture to answer that question for me but you have pieces packed so tightly I can't tell.

Carl

How far have gone?
We started slaughtering MasterPentultimates ...
Great achievement and well edited images.

Carl, yes, it is one part.

Wow! Very nice!!

Very cool, Tom. How the heck did you pack the pieces so well for the print? Is it a Solidworks add-in? Or did you get the Netfabb plugin that Shapeways uses? (I thought it was rather expensive...)

Eitan

Look here:

http://twistypuzzles.com/forum/viewtopic.php?f=9&t=23931

Short answer is he wrote his own software.

Carl

Tom, do you have any plans to distribute this software? I would love a copy!

Does it pack SolidWorks parts into an assembly? Or does it pack STL files into a bigger STL? Or something else?

-Eitan

What Eitan said.

Excellent puzzle Tom. This is definitely my favourite Open Puzzle. Looks like it should be a really tough challenge too.


The latter.

Excuse the posting after a short pause, but I was just wondering- if designed with a 'void' mechanism, could the center stalks be forgone? It looks like it could be done with a void Megaminx, but I know nothing of puzzle design. Though it may make alignment more of a pain, I feel it would make a positive impact on the aesthetics of the puzzle.