Rubik's Cube

One other thought. I know some people use a smart phone to detect initial state of the sides and  communicate back to the solver by bluetoooth...

Pretty impressive work @squeaky,

Both of the woodworking pieces are truly works of art.   And the Rubik's Cube solver appears to be one very well-built machine as well.

I do have a question on your favorite woodworking model.   Are the designs inlays, or were they done by using masks and stains?   I'm just curious because if they are actual inlays that's some pretty intricate inlay work.

I can see where you have the skills to create a large Rubik's Cube that could solve itself by rolling around on the lounge floor as you have said.  You obviously have the skill and talent to pull it off.   That would be a unique project.  You might be the first to create a self-solving Rubik's Cube. 

Hi Stevn,

Yes it is quite a decision....  will think about it

Yes I know George Hart … we had some correspondence a few years ago.

At that time  I think only the two of us appeared to be making these sort of things.

Catch you next week

Joseph 

Hi James,

The decorative sides to these dodecahedrons are all inlayed.

They are done on a CNC machine with very small diameter cutters.... note the sharp corners.

The twelve faces all display a religious motif  … I chose what I considered to be the most popular religions from around the world.

Actually the most difficult part of constructing these types of models is cutting the dihedral angles (the angle between each face)

I do these angles on a CNC and work to three places of decimals. If the dihedral is only very slightly wrong then there is no way that the final shape is going to close the figure. It will be too tight to insert of  or it will be sloppy.

I am enclosing a close up of the star of David. 

Have a nice weekend

Joseph

Posted by: @squeaky

I do these angles on a CNC and work to three places of decimals.

I was thinking this would be extremely critical work.   I'll bet there's still a lot of hand finishing even using the CNC machine. 

Here's another idea for your Rubik's Cube.  Instead of having the traditional colored faces you could inlay mathematical symbols on each square.  The artistic creativity is probably endless.  

You could even have famous equations inlaid onto each face of the solved cube, and those equations would then only be readable when the cube is solved.   Maxwell's equations on one face.  Einstein's General and Special  Relativity on another.  Boltzman's Entropy equation on another.  Schrodinger's equation on another, and so on.   That would really be impressive I think.  Probably fairly unique too, although I don't really know about that. 

Did you hear the story about Schrodinger and Heisenberg getting pulled over on the thruway by the cops ?

Cop : Do you know how fast you were going ?

Heisenberg : No, but I knew where I was

Cop : That's enough funny man. Open the trunk

Cop looks in trunk, and comes back

Cop : Did you know you've got a dead cat in your trunk ?

Schrodinger : I do now

@spyder

You just gave me a new idea!

How about a Escher/Schrodinger Cube?

In the unsolved state it just looks like random cat parts.

Solve it one way and those parts come together to display a living cat on all the faces.

Solve it another way and the parts come together to display a dead cat.

Can it be done?

It would take an Escher genius to figure it out, but they are probably out there.  Someone ought to put the idea out there an an Escher forum board.  I'll bet some Escher fans would work on the problem.   Once they solve the art problem @squeaky could set up his CNC machine to make the inlays.

Just think Joseph, you could have the cube start out in the dead cat configuration on the lounge floor.  Then have it start to roll around transforming itself into a live cat.   Is that cool or what?

@robo-pi

James, you and I would make a great team !

You could come up with crazy ideas, and then it would be my job...

To completely and utterly fail at building them

Just keep the ventilators handy for when my house starts smoking

One last thing on this sort of thing any ideas on constructing a torus knot... using this type of construction.... bit off forum1

Joseph

Posted by: @squeaky

One last thing on this sort of thing any ideas on constructing a torus knot... using this type of construction....

Not knowing the methods used in your construction it's impossible to say.   The torus you have displayed there could have been placed in a lathe or turn table for finishing because it loans itself to being spun easily.  You certainly couldn't do that with a torus knot.

My first thoughts would be to make a torus knot in three identical pieces and then laminate them together to make the completed knot.   Being made in three pieces would allow for better access to each piece during construction.  The three pieces could be made perfectly symmetrical.  At least I think so.  This would allow all three pieces to share any jigs or fixtures you might use to make them.  Then just laminate the three pieces together when they are finished.

That's how I would approach it.   If you're using a CNC machine in the process, you would only need to design the parts for 1/3 of the knotted torus and then just make three of those.

@robo-pi

what a fascinating concept for a puzzle.

The notion of parts that can be assembled in two ways is challenging enough regardless of what the two resulting forms would look like. I guess I would start there and then try to "shape" them later.

But... The more I think of it, being able to create a 3D puzzle that results in a solid sculptural form and yet the parts are constructable using regular tools is actually quite challenging enough for me. I've seen wooden cubes and spheres of course, and the clear plastic apple, but not a lot of other examples come to mind.

stven

@stven

3-D geometry is something a person could devote their entire life to and still not have scratched the surface.  The possibilities are almost as endless as the human imagination.   Plus even if you end up proving that something is impossible that can often bring you fame in the mathematical community.  Assuming no one else had beaten you to it.  ? 

I have a fold-up desk that I designed entire off the top of my head.  I was searching for a design and couldn't find one so I made my own.   I can't find any photos of it, but I have the real thing right here.  I might try to take some photos of it today.

It's a wooden desk that folds up to the size of slightly larger than a large rural mailbox.   When opened up it expands into a desk about 30" wide by 20" deep.  It has 6 drawers and vertical dividers for storing envelopes paper, and even small books.

I'll see if I can get some picture of it today.   It's not exactly a puzzle, but it kind of felt that way when I was designing it.

Wow, I'd love to see the photos.

And here are a couple I did with help from George Hart.

Here are photos of the fold-up desk I designed.  I call it as "Straddle Desk" since you need to straddle the legs when sitting at it.   The first  picture is totally folded up of course.  The second picture legs are folded out to support the desktop leaves.  Then the leaves are unsnapped from anchors that hold them up and then folded down onto the support legs.  Then the front halves of the desktop are folded back.  You can see them partially folded back in the blurry photo. ? 

When they are fully folded back they clip onto the same clips that held the leaves up.  This holds them securely in place.  I designed 6 drawers in this desk.  3 drawers on one of the fold-out sections, and 3 drawers in half of the middle section.  Obviously the arrangement of drawers is optional.   You could have draws in both fold-out sections and none in the middle for a more symmetric look.  Of  if you are a drawer fanatic you could have drawers everywhere allowing 12 drawers in total.

I designed this with the intention of manufacturing them as selling them as "Straddle Desks"  (my trademark name).  I figured that in today's world with so many people living in small spaces they would be in high demand.  I never went into business making them so I'll never know how it might have gone over.  The one  you see in the photo is the only one on Planet Earth. ?   At least of this exact design.  I've never seen anything else like it.  I've searched Google Images for "Fold-up Desk" and have yet to see anything like this one.  So it does appear to be one-of-a-kind.

I designed and built this about 3 or 4 decades ago.   Strangely (an partly due to the fact that I just recently obtained a sawmill), I've started cutting some rough-cut lumber with the intention of making some more. I though I might put some up on Ebay and see what I can get for them.  In fact, I never thought to search eBay for Fold-up Desk.  Let me go do that now,....

Ok, they do have some fold-up desks, but nothing like this.  Most of their fold-up desks are made of modern materials and look rather cheaply made.   Some of the nicer wooden ones they have are actually wall-mounted and just fold down from the wall.   So apparently this baby is quite unique.   I really should make up a dozen and these and see what I can get for them on eBay or Etsy.   They aren't hard to build once you have the design figured out.