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Comment by winkeltripel | Hacker News Reader

I think it can switch drill bits to make fine-passes, and sanding/deburring. I could also be wrong, but I'm lazy enough to want that automated, so CNC probably does it.

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Deep pockets with fine corners are very tricky to machine, since it's hard to make an end mill that's all of long, narrow, and tough enough not to break. I'm sure it's possible, but it would be expensive, and that's before we even talk about the complex tool paths and consequent setup overhead that'd be involved. (And that's assuming there's nothing so deep it'd require EDM, in which case don't even bother asking, you won't be able to afford it.)

There's no mechanical reason why these parts need a fine surface finish anyway, since they're just display pieces. So it makes sense IMO to just do everything via Shapeways, since they already have support for a "white-label" manufacturing service that should make the whole process very easy.

(Hero Forge uses this, for example. It's not true white label since they do mention the partnership, but it may as well be; once you finish designing a model, you pay for the print through the Hero Forge site and a month later you get a box in the mail from Shapeways.)

That said, it looks like Github just gives you a .stl file to do what you like with; the prestige piece in steel looks to be just a one-off for the originator of the software they're using to do the "skylines" feature in the first place. In theory, I guess you could take that STL into Fusion 360 or something and turn it into CNC tool paths, and then you'd just need to find a CNC-equipped job shop that'll turn it into a paperweight for you. (Good luck! And don't expect it to be cheap...)

It's a shame the feature can't seem to see private repository contributions; most of the code I work on daily is hosted in private repos on a Github org, but those commits don't show up here, and that makes for a pretty sad result given that I barely touched any of my personal public repos last year. Nice soundtrack, though!

Found in the Skyline FAQ that you can turn on anonymously sharing private repo contributions: https://docs.github.com/en/github/setting-up-and-managing-yo...

Related: I finally remembered enough of this to look it up successfully! While it's quite old - as I recall, I first saw it posted, in classic photocopier-samizdat style, on a wall of my grandfather's machine shop, when I was a tiny child and he nearing retirement age - I feel it may have new relevance, in these exciting days of computer-aided design and machining, and so post it here for the benefit of all and sundry.

"The Designer" - Author unknown.

    The designer sat at his drafting board
    A wealth of knowledge in his head was stored
    Of what can be done on a radial drill
    Or a turret lathe or a vertical mill.
    
    But above all things a knack he had
    Of driving gentle machinists mad.
    So he mused as he thoughtfully scratched his bean
    "Just how can I make this thing hard to machine?"
    
    If I make this body perfectly straight
    The job had ought to come out first rate
    But it'd be so easy to turn and to bore
    That it never would make a machinist sore.
    
    So I'll put a compound taper there
    And a couple of angles to make them swear
    And brass would serve for this little gear
    But its too damned easy to work, I fear.
    
    So just to make the machinist squeal
    I'll make him mill it from tungsten steel
    And I'll put these holes that hold the cap
    Down underneath where they can't be tapped.
    
    Now if they can make this it'll just be by luck
    Cause it can't be held by dog or by chuck
    And it can't be planed and it can't be ground
    So I feel my design is unusually sound.
    
    And he shouted in glee, "Success at last!
    This goddam thing can't even be cast."

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