

Rodin Bike Wheels - jorgem
https://www.kickstarter.com/projects/1103970298/rodin-bike-wheels?ref=live

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rodinwheels
Hi guys, a good friend of mine sent me the link to this conversation which is
very good and maybe I can add some clarity. Patented 3Drsr is closing the gap
between 3D Printing & mass manufacturing for hollow structural parts. 3D Rapid
Structural Replication allows us to produce parts not possible with injection
molding. In the case of the Rodin Wheels, injection molding cannot produce a
seamless hollow wheel with hook bead rim, internal ribbing and variable wall
thickness where needed to counter stress. 3D Printing can reproduce the wheel
in the same complex form but they are not nearly structural enough, took 32
hours each to build on the FDM printer and ended up costing about $3,000 ea.
In contrast 3Drsr will produce, under high temp and pressure the otherwise
impossible complex fully structural wheel in under 5 mins for less than $200
each during the Kickstarter campaign. Also it really isn't BS that as the
composite material cools it forms and aligns in interlocking chains that make
the final cooled part want to hold the solidified state. As for the tooling
time, we are not planning on employing rapid tooling techniques which we would
normally do for more reasonable sized parts. Thanks for being interested and
talking about 3Drsr Technology and Rodin Wheels.

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quasque
Sounds like they've just slapped a fancy sounding name onto injection
moulding, given that they specify a 2.5 month timeline for tooling.

That said, it's likely a novel implementation of injection moulding technique
for this particular application, and so I don't mean to sound like I'm
denigrating it - but it doesn't seem accurate to frame it as a successor to 3D
printing (as the original HN title did).

Edit: relevant patents assigned to the founder of the Kickstarter campaign -
WO1994016911A1, WO1995004666A1; this is definitely injection moulding

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jorgem
The title did get changed. I think the reason it was titled "after 3d
printing" was because you can make a prototype with 3d printing, but what do
you do when you want to go to production?

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devinmontgomery
I got nothing from the project description, but here's the patent:
[https://www.google.com/patents/US6516866](https://www.google.com/patents/US6516866)

It sounds like a mashup of injection molding and lost wax casting (what they
call "lost core molding").

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fest
Once I got to the part about material memory and molecular level, my bullshit
detector tripped.

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JackA
Well, I believe polymer chain alignment is used quite a lot in manufacturing
to improve strength in the desired directions. However, given that I couldn't
see any info on what this '3DRSR' actually is, I am also sceptical. At the end
of the video the bloke mentions needing to pay for tooling.... is this for
their '3DRSR' machine, or do you need tooling to be made for each 3D printed
part, in which case it isn't really 3D printing?

Sounds rather like they're throwing in some buzz words to make their plastic
moulded wheel sound cool.

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rodinwheels
jorgem has it right. If you can get your mind around how complex it really is
to make the entire wheel hollow with ribs inside with the flowing spokes
getting wider as they get closer to the hub area while at the same time the
wall thickness is increasing this can not be produced with "injection molding"
3D Printing can make duplicate the shape but the printed wheel is too weak,
takes a lot of hours each to make and costs way too much.

3Drsr Technology sets designers free to make amazingly complex hollow
structural parts quickly and at reasonable cost.

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taybin
4D printing obviously. I want this in my hand:
[https://www.youtube.com/watch?v=5xN4DxdiFrs](https://www.youtube.com/watch?v=5xN4DxdiFrs)

