Friday 29 April 2011

Stewart Coffin Seven Block

One of the puzzles in the box from Kayleb’s Corner was a Stewart Coffin Seven Block puzzle. I hadn’t been able to find out anything about it in a brief search on the web before I ordered it and it’s always hard to tell what you’re in for when you get an unknown cube assembly / disassembly puzzle like this. I was hoping that I wouldn’t be disappointed, but the Coffin moniker should have been all the reassurance I needed...
The puzzle came in a cute little decorative box with no particular markings on it, and the puzzle itself is a reasonably non-descript 4*4*4 cube made of maple. There’s a little white sticker with the words ”Stewart Coffin Seven Block “ on one side, but other than that, it looks just like a simple cube construction. So you take it out of the box carefully, just so that it doesn’t fall apart (Yeah, right! Little did I know...) and start looking at the cube – no obvious easy ways in, no pieces trying to make a bid for freedom yet – looks nice. 

OK, so it didn’t fall apart – good start ... so let’s find a way in – start pushing and pulling at the most likely candidates, hmm, not much give at all ... OK let’s try some of the edges – nope, nothing there. Corners? Nope. Opposite corners? Nope ... Hmmm ... Ah!! I know, friction along the faces in many directions – maybe it’s one of those co-ordinated motion cubes ... 6 faces later, nope, not that either ... Retreats to think while placing the puzzle back in the box...

Thinks ... for a while ... comes back to it a while later (not quite so careful about taking it out the box this time!) and tries a few new theories – none of which do anything at all ... 

Hmmm, maybe it’s one of those in-jokes, you know the ones where the pieces are all actually glued together? Given how little movement there is between the pieces, this could actually be feasible! Puts it away to think some more ... and laugh at the fact that I was worried about it falling apart or not presenting much of a challenge!
A couple of sessions later I finally manage to work out how the key piece works, and it’s brilliant! 

It keeps its secrets incredibly well hidden, and even once released, the rest of the cube is slow to give up its secrets – it’s like peeling and onion until you eventually have the seven pieces apart – ah, so that’s where it gets its name from. [Yes dear eagle-eyed reader, there is a piece missing from that picture - the key-piece, just to make it a little more interesting for you...]

While I was writing up this post I got hold of Georges to ask him about the puzzle and it turns out it came from Bernhard Schweitzer and there’s a short write-up in Bernhard’s Puzzlewood Gallery.

It’s a cracking cube puzzle...

Late addendum: I had to smile when I noticed this... I'd used my favourite search engine when I was trying to find out about this puzzle, and turned up not a lot... so I had to smile when I noticed that one of the traffic sources for for my blog was in fact a Google search for "stewart coffin seven block" - and this is now the first page you get when you search for that... which just goes to show that not enough people have been writing about this puzzle on the web!


  1. Thanks for writing about the Seven Block - glad to see this puzzle is being made! It is a great design, but I think it tends to be a bit forgotten.

    I made several of these a while ago and really enjoyed the design. The CD I sent to Chris will have some photos on it of the Seven Blocks I made.

    Thanks again!

  2. Brilliant Scott - it'll definitely find it's way onto the wiki then! This one really surprised me as a great little puzzle...