Christmas Ornament RBS

I've gotten some feedback on http://groups.yahoo.com/group/rollingballsculptures/ ...

Here's one person's message:

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Christmas Ornament RBS on Shapeways

Hi Jim:

That is amazing, truly. You are a pioneer. In a few years companies might
even be printing out of metal.

How much bigger can these be printed?
A one inch ball and a two foot wide piece?
And will they print in other colors?
Are that many connectors required, or could the number be halved?
And if you wanted to add a switch, and have two tracks, you could use a
large washer like what I use on my work, where the ball falls through the
(slightly larger than the ball) hole in the washer and falls randomly onto
either of the two tracks below. No moving parts - perfect for this printing
application. You can see this in work on the videos of Blue and Twinkle on
my web site: www.stephenjendro.com.

Great work there Jim.

Stephen

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Here's my response:

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Christmas Ornament RBS on Shapeways


Thanks for the kind words.

BTW, Shapeways already prints in stainless steel!!!

The reason why I made it small was because they charge by the volume of plastic
(or metal) that you use not by the bounding box. So for example a 2 mm wide 10
cm long stick straight or wound up would cost the same. So the smaller you make
it the cheaper it will be.

The rbs christmas ornament in plastic is like $10 and in stainless still is like
$50 something. So you can see it costs a lot more to print in metal but yes,
that would be the ultimate goal that I would like is to print it in metal if it
just wasn't so darn expensive to do.

Making bigger ones of course would become prohibitively expensive very quickly.
They do have size limits but you can make fairly big objects in steel:
100x45x25cm. And of course if you're crafy enough you could make sections that
could be joined together if you need to make things bigger than their printing
size limits. You can find out more about their materials and size limits on
their materials options page: http://www.shapeways.com/about/material-options

One way to save money is to hollow out the inside to save volume. You have to
leave holes for the support material to come out. So if you made a 1 inch ball,
you'd probably want to make it like a whiffel ball with holes so that the dust
inside could be shaken out. Otherwise, if you made a solid 1 inch ball in steel
it might be very expensive! It would be tons cheaper just to buy a 1 inch
bearing somewhere else than to have them print it.

Small RBSs may be ok, but Shapeways may not be practical for making bigger RBSs
anyway because of the expense. Perhaps Shapeways might be nice for making
special jigs or making parts of an rbs that could be copied or reproduced or
even for making a mold to reproduce rbs parts or something like that. Or for
that hard to make feature that makes your RBS cool! But probably making a whole
big rbs from Shapeways would be too expensive for my current income level.

They have some other colors but they basically dye the entire part. Like you
can't print individual voxels (3d pixels?) in different colors. I wish they
could, that would be awesome. You can paint the parts, though, so at least
there's that.

On the connectors, rungs, yes, I could probably get away with a lot less
connectors. I just chose a distance that looked ok to me. I'll probably reduce
that in future rbs like you probably suspected.

You can create moving parts! You have to leave about 0.5mm distance between the
axel and the hub and you can have a moving part. Any closer and a hub may get
fused to the axel. So you could make hinges and such. The flexible platic
material choice is flexible enough that you can even design a spring into your
design. With steel and the other plastics they're too tough to do that, though.
So one guy made a wind up car. What's cool is it comes out of the printer
completely assembled gears, spring and all and just works. One guy is in the
process of making a whole wall clock gears, pendulum and all that will be
completely assembled and work right out of the printer. 3d printing is very
cool and definitely worth looking into!

Thanks again.

Watch the video: http://www.youtube.com/watch?v=ikVwr1E6hoo