[HN Gopher] Making a Stainless Steel Rubik's Cube
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Making a Stainless Steel Rubik's Cube
Author : camtarn
Score : 168 points
Date : 2022-03-25 14:18 UTC (8 hours ago)
(HTM) web link (lulabs.net)
(TXT) w3m dump (lulabs.net)
| CarVac wrote:
| I never realized before that the sliding surfaces inside the cube
| are cylindrical, not spherical.
| s1mon wrote:
| Doing some quick image searches for teardowns, it seems that
| different models have been done both ways. Some with spherical
| bearings and some with intersecting cylinders. It makes some
| sense that either way works, as you're only ever rotating
| around one axis at a time.
| jacquesm wrote:
| Wow, what a gorgeous piece of work. If you ever want to make
| something out of 304 and you're having problems: if you are too
| gentle with your cuts it will tend to 'smear', you _really_ need
| to cut, probably a lot more aggressive than you might think if
| you are used to taking it easy on Aluminum and other soft metals
| which are pretty forgiving. 304 is not. The machinists joke is
| that it isn 't hard, it's just hard to work.
| at_a_remove wrote:
| I saw a video
| (https://www.youtube.com/watch?v=4iB7kkCy1xM&t=160s) on EDM
| machining and the tolerances were magnificently tight. I had
| since wondered if such techniques would work for building a "one-
| move" Lemarchand Box ( _Hellraiser_ ), assuming that engraving
| various designs would utterly obscure the actually disjoint
| pieces.
|
| I am not sure what steel you would need. Something dimensionally
| stable, to be sure.
| Damogran6 wrote:
| I just bought a shower cassette removal tool (looks like Moen
| 104421), it's machined aluminum. I'm pretty sure I could make it
| myself...I couldn't make it for $15 and no time spent. This makes
| me sad.
| RobertRoberts wrote:
| He missed an opportunity to color the engravings on each side
| with the same colors from the original cube. I think it would
| have looked even better. But still incredible regardless.
| lisper wrote:
| My first thought was: how the heck could you assemble a metal
| cube? Putting a plastic one together relies on the springiness of
| the material in order to place the final piece, but metal won't
| give in the same way. The solution:
|
| > The face centers each receive a hollow stem that screws into
| the 5/16-24 thread. This assembly holds a captive spring-loaded
| screw, which screws into the core. The spring provides some give
| to the entire unit and allows the cube to be assembled and
| disassembled easily by snapping pieces in.
|
| Brilliant!
| globular-toast wrote:
| I had the same thought but just tested with a fairly standard
| "premium" plastic cube (not Rubick's brand) and I think it
| works in the same way. There are springs and that allows
| assembly/disassembly and I think it would work with a less
| flexible material. Not sure if the Rubick's brand ones are the
| same or if they really do rely on flexible plastic.
| mjb wrote:
| That's very cool, and a beautiful piece in the end. Good choice
| to do it in 303. 316 really is a pain.
|
| The ingenuity required to get things like this one on manual
| tools (especially pre-DRO, but even now) is amazing. Starting out
| machining, I expected the machining to be the hard part, but
| often a lot more time is spent on planning, fixturing, set-up,
| and so on. For example, the idea of making custom vise jaws to
| hold odd-shaped parts seemed crazy to me the first time I heard
| it, and now its just a completely normal way to behave. CNC makes
| things a whole lot easier, from being able to do complex shapes
| with CAD/CAM, to simple things like interpolated circles (when
| the mill cuts a circular shape by moving X and Y simultaneously,
| a seemingly trivial thing that's nearly impossible on a manual*).
| Having a 4th or 5th axis makes complex stuff even easier, and
| often completely avoids the need for wacky fixturing.
|
| The lathe fixturing here is especially fun. A lot of old hobby
| books are written assuming you have only a lathe and no mill.
| Fun, often scary, fixturing was the order of the day.
|
| * Ok, you can do crazy things with boring heads, but getting it
| right is really hard.
| jacquesm wrote:
| Yes, fixing stuff is one of the harder problems, as is avoiding
| toolstrikes or having to re-grip something because your
| carefully laid plans are messed up by the cutting depth or
| stability of your tools. Sometimes you spend more time figuring
| out how to safely grip a workpiece than you do on the actual
| machining.
| bsder wrote:
| "Devil's chewing gum" describing 304/316 stainless for
| machining is pure poetry.
| nickcw wrote:
| A mirror cube made like this would be perfect as it doesn't need
| any markings on the faces.
|
| https://en.wikipedia.org/wiki/Mirror_blocks
|
| (The mirror cube is my favourite shape mod!)
| aardvark179 wrote:
| A ghost cube would be nice too.
| selectronics wrote:
| Very cool!
|
| Follow up idea, which I'm sure adds tons more complexity: have
| each face be a different material or finish. E.g. one face is
| stainless, another anodized aluminum, zinc plated for a third,
| brass on another. Each of the edge pieces would have to be a two-
| part assembly, and the corners composed of the three materials
| joined together (joinery, screws, brazing).
|
| That surely would feel strange with the varying densities and
| thermal masses while solving, but would look very cool. To be
| fair, it appears from the pictures that each center piece's
| pattern is symmetric, which avoids the difficult part of aligning
| those when solving (center often doesn't line up when solving a
| cube with pictures on the faces in place of a solid color).
|
| Probably far too niche for selling these to be profitable, but
| I'd love to have one.
| jstanley wrote:
| > center often doesn't line up when solving a cube with
| pictures on the faces in place of a solid color
|
| I don't understand this. If you have a corner piece in the
| wrong corner then won't the colours on the adjacent faces be
| wrong?
| BoppreH wrote:
| The corner and edge pieces are guaranteed to have the right
| orientation, but the center pieces can be in any 90deg
| orientation. Imagine an arrow printed on a center piece; a
| cube can be solved and still have that arrow pointing to any
| of the 4 neighboring sides.
|
| Here's a video explaining special algorithms to rotate only
| the center piece: https://www.youtube.com/watch?v=fk1eCZNCTB4
| jstanley wrote:
| Ah, interesting, thanks! So it's possible to reach a
| configuration where _every_ side has the centre rotated but
| all the colours match up. I would not have believed that
| without seeing it.
| somebodynew wrote:
| I think that it would be difficult to keep everything clean
| enough to avoid galvanic corrosion at the metal interfaces once
| someone has touched it. I experienced surprisingly rapid
| corrosion when securing copper lugs using zinc-plated steel
| nuts and bolts until I started handling them exclusively with
| gloves.
| gotaquestion wrote:
| My tendons are cowering in fear. How fast does it do finger
| tricks? It seems like there'd be a lot of resistance since so
| much surface-to-surface contact, where speedcubes typically flex
| on springs so that the shape of the cube changes to cut rotation
| on different curved planes.
| DominoTree wrote:
| You opened the box... we came
| derbOac wrote:
| I would have liked to hear more about why the author was
| disappointed with the aluminum cube. I'd think it would be
| lighter and easier to handle.
| ummonk wrote:
| From the article on the aluminum cube:
| http://lulabs.net/machining/cube/
|
| > The flat bottoms of the face centers do not allow the cube to
| turn as smoothly as it should; a problem that was rectified
| with a different design in the new cube.
| jhgb wrote:
| I was kind of hoping the faces would be heat-colored but I
| imagine that would have been a bit more complex.
| convolvatron wrote:
| just need an oven with good temp control. there is this lovely
| bronze color you can get on stainless.its strangely alot more
| stable than color you get from heat treating mild steel...but i
| bet it would rub off if you used it a nontrivial amount
| jhgb wrote:
| The problem I imagine would be with the corner pieces. You'd
| need three different temperatures for the three different
| faces (with stable temperature across each face). I imagine
| that achieving this might be still technologically possible
| but almost certainly non-trivial.
| skykooler wrote:
| The only way I could see of achieving that would be to heat
| each face very rapidly with something like a high-powered
| infrared laser, so it can reach oxide-forming temperature
| before the heat has time to spread. The low thermal
| conductivity of stainless steel compared to many other
| metals would actually be rather useful here.
| s0teri0s wrote:
| I wonder if it is whisper quiet in use, or if it makes any kind
| of scraping noises when manipulated.
| huhtenberg wrote:
| Sort of tangentially related. Had this page bookmarked years ago
| because the craftsmanship on the puzzles is absolutely incredible
| -
|
| http://www.pelikanpuzzles.eu/en/gallery.html
| woah wrote:
| This may some day be the last remaining Rubik's cube
| Dig1t wrote:
| This is so cool, stuff like this makes me wish I had studied
| mechanical engineering instead of computer science.
|
| Does anyone know of a good route for learning the software stack
| associated with this stuff? I keep up with some maker YT channels
| like Stuff Made Here and they usually do an okay job of showing
| which machines were used and how each piece was made. But what
| they usually never show is which programs they used to model and
| mock up their creations before they started machining.
|
| I'd really love to learn more about CAD modeling and designing
| these kinds of projects but I don't know how to get started.
| mjb wrote:
| This Old Tony, Blondihacks, Wintergatan, and others have done
| end-to-end videos from CAD to machining to assembly. I
| particularly recommend Blondihacks' beginner videos: well
| produced, fun to watch, and cover nearly everything you need to
| know to get started.
|
| Also, face the reality you won't be doing work like this on day
| one. But you will make something fun.
| 42jd wrote:
| Wintergatan is doing a lot of live design/cad sessions the
| past few weeks on his "wintergatan live" channel which might
| be useful or interesting
| skykooler wrote:
| Clickspring's videos are also full of excellent tips,
| particularly for small lathe work.
| sokoloff wrote:
| I'd add Clough42 to that excellent list.
| maicro wrote:
| I don't know of any great resources, but from my personal
| experience and understanding of the landscape is that Fusion360
| is the most common real CAD program used by hobbyists, and
| small shops (especially those that are basically "hobbyist
| bought a bigger mill and moved into a larger garage"). Some of
| the bigger places will use SolidWorks (which is what 95% of my
| CAD experience is in), but the price there is way out of the
| range of someone just trying to learn.
|
| In general, the aspect you're asking about is called an
| "assembly" - where you can bring in multiple parts that you
| have designed (and even design new parts "in place") to see how
| they go together and, to a minor extend, interact. I say "minor
| extent" there because most assembly systems aren't running full
| physics simulations or collision detection, at least most of
| the time - SolidWorks will happily let you design and assemble
| a model that is physically impossible to put together, while
| letting you rotate bodies through each other.
|
| So yeah, I'd recommend starting with Fusion360. There are
| plenty of resources out there for learning it, but I do know
| that Grimsmo Knives and NYC CNC have videos showing how they
| specifically use it.
|
| Here's what seems like a very in-depth video from Grimsmo on
| 5-axis machining (so definitely not applicable to just starting
| to learn, but this is the first I found - I know plenty of
| their other videos have details about fixturing and setup):
| https://www.youtube.com/watch?v=XqhctiVZtRU
|
| NYC CNC has an entire playlist called "Fusion 360 for
| Beginners": https://www.youtube.com/nyccnc/playlists ; I
| haven't watched any of that, but I've watched plenty of their
| videos and enjoyed them, so think that playlist should be at
| least a bit helpful.
|
| There's plenty more detail here, but I don't have the time at
| the moment to dig deeper - if you have any questions, feel free
| to leave them here and I'll see what I can dig up.
| nereye wrote:
| > Some of the bigger places will use SolidWorks (which is
| what 95% of my CAD experience is in), but the price there is
| way out of the range of someone just trying to learn.
|
| FWIW, SolidWorks does have a low cost option ($99 a year):
|
| https://discover.solidworks.com/makers
|
| And arguably there also features included in the above that
| are not available in the free version of Fusion 360
| (available in the paid version, which has similar licensing
| costs to full blown SolidWorks).
| thequux wrote:
| Solidworks now has a version for makers that costs
| EUR100/year. IMHO, that's a completely reasonable price for a
| tool of that caliber.
| Dig1t wrote:
| Wow, thanks so much. This is super helpful!
|
| I'll absolutely dig into this stuff more. Even just knowing
| about the assembly thing is very helpful.
| teraflop wrote:
| Fusion 360 has a free version and is very approachable. It's
| pretty popular among 3D printing hobbyists, but you can use it
| for all kinds of 2D and 3D designs.
| newaccount74 wrote:
| Fusion 360 is pretty neat for hobbyists. I've used it for 3D
| printing and for CNC milling in a makerspace.
| s1mon wrote:
| Onshape also has a free tier [0] and is popular amongst
| hobbyists and education.
|
| [0] https://www.onshape.com/en/products/free
| jwise0 wrote:
| I was Chris's housemate at the time, the victim of the
| hours of 'sssshhhh sssshhhh shhhhh'. Interestingly, he
| rendered this mostly by drawing boxes in pov-ray -- I'm not
| sure what he used to make dimensioned drawings, but it was
| definitely not any of the modern CAD tools, and they were
| mostly for his reference.
|
| But these days, I _do_ highly recommend Onshape -- it
| breaks down a lot of the 'rules' that I thought I knew
| about CAD software. I started using it about two months
| ago; one of my clients uses it for real industrial design
| of some IoT hardware, so it is powerful enough to do real
| things. Before I started using Onshape, I thought that 1)
| all CAD software was a million billion gigabytes, and
| required stupidly powerful hardware for no readily apparent
| reason, and 2) had an annoying licensing model that
| requires you to jump through hoops to get access to the
| free tier. Well, neither of these are true with Onshape: I
| went from 'hmm, maybe I should try this for my personal
| projects' to 'constraining a sketch' in about 90 seconds
| ... on Linux ... in Firefox ... on my Shenzhen ThinkPad ...
| with an Intel GPU. I was blown away at how much it failed
| to suck.
|
| Anyway, my suggestion on choosing software is: it probably
| doesn't all that much matter. What you want to learn is the
| CAD mindset, not the software. An experienced MechE once
| told me that if you are not careful, you can end up writing
| 'spaghetti CAD'. These tools these days give you a lot of
| features that are, in theory, more expressive, but in
| practice, can result in unmanufacturable parts or
| unmaintainable designs: be careful!
| jhgb wrote:
| > Before I started using Onshape, I thought that 1) all
| CAD software was a million billion gigabytes, and
| required stupidly powerful hardware for no readily
| apparent reason
|
| So I take it you have never seen OKAD? ;)
| http://www.ultratechnology.com/okad.htm
| ehsanu1 wrote:
| Watch all the CAD streams from wintergatan live.
| Melatonic wrote:
| I would say start messing around in Blender and do a few basic
| youtube tutorials just to get a feel for sculpting
|
| Then you could probably test using a desktop CNC machine at
| some kind of maker space (or even some libraries now have
| them!)
| Klaster_1 wrote:
| So I'm a software engineer too, but also a cyclist. A
| weightweenie. At certain point, you begin to mix and match
| totally incompatible parts, solvable with a modest
| manufacturing capability. For me, the learning path was
| basically the same as with programming - lots of motivation,
| access to internet and tools (a machinist). Back in school, we
| were taught part sketching and machining basics, which helped a
| bit. I picked FreeCAD out of available open source solutions,
| watched a lot of great tutorials on YouTube and, though trial
| and error, managed to produce designs good enough to serve the
| purpose. Machinist services in Russia are incredibly cheap,
| especially if they have their own machines in a garage. With
| small beginner projects, the price of error is just your time
| and materials, don't be afraid to experiment.
|
| On a side note, my mechanical engineer acquaintance complains
| that he should have followed the CS route because programmers
| earn substantially more here. The grass is greener.
| Izikiel43 wrote:
| Or you can be this guy, who has a Bachelors in Mechanical
| engineering, a Masters in CS, and does crazy stuff:
|
| https://www.youtube.com/c/stuffmadehere
| httpz wrote:
| It may not the most suitable for hobbyists but your local
| community college may offer some classes and access to machines
| at a very affordable price.
| SapporoChris wrote:
| I definately enjoyed the article, but apologies. I enjoyed the
| referrenced article https://kellycordes.com/2009/11/02/the-fun-
| scale/ much more. Perhaps it's just my mood at the moment, but it
| had me laughing out loud.
|
| Regarding the Stainless Steel Rubik's Cube. What a work of art!
| camtarn wrote:
| I also loved the linked article - the concept of Type II Fun is
| definitely one I'll be adding to my vocabulary :)
| damir wrote:
| Shut up and take my money!
|
| Seriously, I want to buy this, like right now...
| tintor wrote:
| Same! Especially the heavy steel one.
| idoh wrote:
| Same. How much would you pay? I'd do $500 easy.
| jamestimmins wrote:
| This is extremely cool!
|
| I wonder if the relative similarity of the designs on the faces
| makes it particularly difficult to tell them apart, although if
| it's mostly for display that shouldn't matter much.
| omoikane wrote:
| > Although it may be neat to look at, it weighs a massive three
| pounds (~1.4 kg) and is very tiring to manipulate. Solving this
| is more a test of the wrists than of the mind!
|
| This was the punchline I was looking for. The aluminum version
| seem like a more desirable version at 500g.
| chaoxu wrote:
| I wonder if one can hollow out the individual cubes to decrease
| the weight.
| lapetitejort wrote:
| Or you could increase the weight by using tungsten or
| depleted uranium.
| isoprophlex wrote:
| Weighs more than a kg... Makes me wonder if machining a tungsten
| Rubik's Cube is feasible
| tintor wrote:
| In Tungsten: 41.6lb / 18.9kg. Train your mind and your arms at
| the same time.
|
| https://www.thisiswhyimbroke.com/the-4-tungsten-cube/
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