# DIY - Rubik's Cube - Blind Man's Cube - Metal Rubiks Cube

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## Introduction: DIY - Rubik's Cube - Blind Man's Cube - Metal Rubiks Cube

This is a Rubik's cube the is shape-oriented rather than color oriented for solving in the dark or for those who are without sight. It is inspired of the now unavailable "Blind Man's Cube" that was made years ago by Politechinka. See: http://www.twistypuzzles.com/cgi-bin/puzzle.cgi?pid=63&allprices=1

This cube brings a unique characteristic to solving a Rubik's cube that no other cube does... the ability to say "I solved it without even looking at it once."

Rather than building hand-eye coordination, it builds hand-mind coordination.

I find that solving this cube is a challenge above and beyond a normal rubik's cube. It takes me significantly longer to solve than a normal cube. But as a result my speedcubing times on regular cubes have dropped exponentially. Because it uses areas of my brain a normal cube do not (memory/perspective... seeing it in touch and shapes rather than eyesight and color).

It is also a bit heavier than a normal rubik's cube... helping me build muscle/speed for my speedcubing (speedcube is where you try to solve it as fast as possible.)

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## Step 1: What You Need

To make this cube you will need the following:

-A Rubiks's Cube (authentic or fake)
-54 Uniquely Shaped Metal or Plastic Tabs (more on this in how-to)
-2 Part Epoxy for use with plastic/metals
-Toothpicks or like for mixing/applying epoxy
-Duct Tape
-Isopropyl Alcohol
-Paper Towel(s)

## Step 2: Obtain Rubik's Cube

First of all any rubik's cube will work. It is estimated that over 300 million authentic or knock-off Rubik's Cubes exist. This should cost (at time of typing this) around \$10 for a new authentic Rubik's cube. However there are a TON of them on E-Bay for much cheaper.

## Step 3: Obtain 54 Round or Raised Square Metal Tabs of 6 Different Raised Shape Designs

You are kinda on your own for this one, I pried mine off of an old chair in my garage and filed the backs off with a dremel. If using an authentic sized rubik's cube, these will need to be smaller than 5/8th's of an inch square, and preferably no deeper than 1/16th of an inch (or the cube will become noticably cumbersome in size). If you can only find 5 shapes... don't fret... remember that a single side missing shapes is still an identifyer (provided all other sides have identifyers). Other options (not as cool looking in my opinion) are sandpaper, wood, cardboard, plastic, etc. Scrapbook or craft stores might be a good place to shop for something like this.

WARNING 1: The Designs must FEEL different from each other. Each shape needs to have a distinguishing characteristic to differentiate it by touch rather than sight. THIS IS IMPERATIVE.

WARNING 2: It is best to ensure that each of the 6 shapes is quadratically symetric* in design (i.e. turning the shape 90 degrees yeilds same design as before turned). This ensures that after mixing and solving... the cube looks complete (note that one of my shapes does not follow this rule).

Many who are new to Rubik's cubes are unaware of the fact that if you were to draw arrows on each square of the cube when you buy it, solving it to perfection is not as easy as some pieces will not be soundly placed (arrows in all same directions). See picture for understanding... you see the colors are all in place... but the cube is not truly solved. Unless you know how to solve a cube like this... you will want to ensure the designs on the tabs are symetric as I mentioned.

• - I am not sure if this is even a word, it just made sense in my juvenile vocabulary.

## Step 4: Peel Stickers Off Cube

I used my fingernail to remove, and then used isopropyl alcohol to deal with left-over adhesive. Also... the stickers are a TWO-PART sticker in that the color is covered by a second sticker of Clear-coat (this may not be the case in non-authentic or legacy Rubik's cubes). So make sure you get both.

## Step 5: Etch the Cube in Prep for Epoxy

Using your choice of a razor blade (careful!!!) etch the center of plastic squares with 8-way cross-hatch so that Epoxy will hold better to the etch than just the smooth plastic (this may not be necessary if the glue you use bonds to the plastic).

## Step 6: Etch Back of Metal Tabs/pieces

Like you did with the center if the Rubik's cube centers... Using your choice of a razor blade (Serious... BE CAREFUL!!!) etch the backs of the metal tabs with a 8-way cross-hatch. To do this safely I layed a piece of duct-tape upside down and used two pieces of right-side -up duct tape, and laid the tabs down accordingly, then etched the back with a box-cutter knife with a new blade.

## Step 7: Clean Cube and Tabs With Alcohol

Clean backs of tabs and surfaces with isopropyl (or your choice) of alcohol... this ensures the bond will not be effected by fingerprint oils and any other foreign materials.

WARNING: This will not harm an authentic Rubik's cube. If your cube is not authentic... it might be made from a form of Acrylic... if this is the case either SKIP THIS STEP, or use soap and water and let completly dry... as alcohol would melt/crack/damage your acrylic cube.

## Step 8: Epoxy Pieces to Cube

Using a 2-part epoxy, bond each side of 9 shapes to the cube centers. Use as little as possible but ensure a complete bond.

NOTE: I would have used gorilla glue, but did not want to clamp these down (a necessary step requiring clamps I did not have). Also... Gorilla Glue (as awesome as it is, seriously that stuff HOLDS) expands 3 times and if not used carfully would look messy... because of this I used a Super-Glue based 2-part epoxy.

## Step 9: You Are Done! Metal Rubik's Cube Complete.

Congrats! Contact me if you have any questions while building one.

Additional Note: I left the center piece (originally covered by white stickers) out that shows the engraved "Rubiks" logo. While solving I found it had a good impact in identifying that side and it looks cool (my opinion).

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## 153 Discussions

bro it looks good but ,there is a problem where do find the tabs

Where did you find the metal tabs?

Here is a guy who knows his stuff.

For anyone else trying this or anything like this: I've found that you can pretty thoroughly remove the leftover adhesive from the cube faces using the stickers themselves. Just push them onto the leftover glue, remove, and repeat. A dozen or so sticks on the leftover glue and it's pretty clean.

I'm using this personally, as I don't want to take the extra time to truly clean the faces, and I'm finding it works fine and does a decent job.

Wow! This is awesome! I am so grateful for this post. My dad is blind and his wife is legally blind. They are coming down to visit for father's day. I'm always looking for something new to add to the trip and this will be perfect! In case anyone out there was checking specifically for activities or games blind people can enjoy- my dad loves to play- bop it. You can pick one up at walmart for about \$18 usually. http://www.hasbro.com/games/en_us/bopit/

My attempt. I'm going to give it to my dad this weekend for Father's day. =)

Another thing people don't know is that unless you take the cube apart and put it back together wrong, there will always be an even number of incorrectly solved centers, unless they are all correct. That being said, if you can solve a Rubik's Cube with a beginner's Layer method, then you can at least make sure 5 of the centers are correct while solving, thus the last will with automatically have to fall into the right direction.

that's not true: centers never move, they can only spin in place the opposite centers are always opposite all other pieces can move, but corners stay as corners and non-corners stay as non-corners

The terminology of "incorrectly solved centers" is just relativity: either the centers are fixed (and always solved) while the sides and corners move around them, or you "solve" a framework of sides and corners in situ while the corners move through that framework. Arguing about which perspective is "right" is equivalent to arguing about the "reality" of centrifugal vs. centripetal forces.

The centers are not "always solved" in the true sense of the word. Arguing about which perspective is "right" does merit some gravity. According to Rubiks there is "only one solved state" which is denoted as "all faces of 9 squares having the same color". However this is not one solution, there are hundreds (thousands?, I am lazy today and don't want to research the math, anyone else game) of possible "true" states that merit the cube being "solved" by Rubik's rationale. That is because even in a solved state... the 6 centers still have 4 possible states each of rotation without you knowing if it is in the "original pre-scrambled state". Only with a supercube can you truly know if you solved it 100%... as the centers have an arrow denoting the "truly" solved or unsolved state of the center peices. That is of course if you want to get down to that level of solving... if Rubik's solution befits your lifestyle... so be it.

No, there is only 1 solved state. The centers are fixed with the edge peices rotating around the cube, in the x, y, and z vertices. So if we are looking at the blue face, and the orange face is to the right, then there is an edge piece in between them that is both blue and orange. This piece needs to return to that same spot. That particular piece has two faces, which cannot move Independently of each other, and must be in that particular spot to be correct. There is only 1 solution to the Rubik cube, and only 1 state that fits the bill.

Good points. I was using "solved" in the same sense as Rubik: the visual (or tactile, given this I'ble's topic :-) appearance of the exterior surfaces, rather than the internal degrees of freedom.

Something I don't know is whether it is possible to manipulate a cube such that a given center (or combination of centers) can be rotated relative to the edges and corners, while ending up with the same solid-color faces. This is your second point; it may in fact be impossible given the engineering of the joints.

As for the number of solved states, we can do the math here. The corners provide a reference frame -- because each one has three unique colors,
their positions relative to one another are fixed, so therefore there is only 1 solved state for them. With the corners fixed, each edge in turn can have only one position and orientation, and therefore there is also a single solved state.
That leaves only the four internal degrees of freedom for the six centers; the total number of such states would be 46 = 212 = 4,096.

Again, I don't know whether those states are reachable. If they are, then your discussion above about the meaning of "solved" is on point. If not, then the solution state is unique for any cube which is not disassembled and reassembled.

The centers can only be rotated in pairs. So instead of 4^6 = 4,096 states. We have (4^6)/2 = 2048 states. If there are arrows on the faces, then only one will be the solved state. Rotating the centers in pairs is not difficult however. So getting the "quadrilateral symmetry" for the tiles is not needed.

There are permutations that allow for cycling the center in a supercube, they are asked about a lot on boards, and I don't know them by heart. thanks for hitting the math... so there are 4,095 possible solutions that are not true... very interesting. That being said... I hate supercubes. lol.

Grandpa: I solved it!!!! Kid:Solved what? Grandpa: Supercube Kid: In like what, a week? Grandpa: 72 years!!! Kid: You have no life (Grandpa has a heart-atack and promtly dies)

good point, did not think of that, um... that would be cool if there was a instructables on how to make a printer that printed morse code... super power full lazer printer! he he!

Braille printers exist. They take heavy braille paper and use pins to punch in the braille.