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• #577
just empty a bottle of ink on yer dining table then.can anyone tell me apart from copying the sloping t tube what else he has done.no slight, a genuine question.
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• #578
yeah,bit like that barmaid i got off with
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• #579
i agree to an extent its a very grey area between style and art to the engineers giving it the v sign
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• #580
3d titanium full sus MTB. I saw this in the flesh at some trade show I went to in Birmingham. As mentioned above all the tubes have internal webbing. Ignoring the actual design of the bike, technically it looked ok.
http://www.pinkbike.com/news/Worlds-first-3D-printed-bike-2014.html
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• #581
yeah must be fun to go down hill for a good 20mins
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• #582
As for 3D printing, I am wondering... Does it produce structurally strong pieces (compared to forged metal, for example) ?
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• #583
Due to the UCI we ARE stuck with conventional frames forever.. unless you want to grow a beard and wear sock/sandle combo and ride HPVs.
Oh and for modern frames design see CFD and wind tunnels not Faber Castell.
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• #584
Surely they'll have to change the rules sometime?
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• #585
Can you imagine the TdF with the whole peloton in...
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• #586
Of course they'll have to draw the line somewhere, but stuff like:
Should be allowed.
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• #587
I'd rock the last two.. but only for my commute.
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• #588
This:
is actually quite good...
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• #589
As for 3D printing, I am wondering... Does it produce structurally strong pieces (compared to forged metal, for example) ?
Not as materially strong as some traditional metalworking processes, although the best additive manufacturing processes can get pretty close, and make up the deficit by more precisely putting the material where, and only where, it is needed, so for a given mass, the structural strength can exceed legacy methods, since some complex forms simply can't be made by traditional processes so the final component retains some essentially redundant material which traditional tooling couldn't remove.
If your legacy process was casting (as it was for high end frame lugs), I think Selective Laser Melting might actually be able to produce better results, as there is potentially tighter control on the cooling rate.
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• #590
stuff like [unlikely collection] Should be allowed
The problem the UCI has is in regulatory draughting. They made enough of a balls up when they just drew a bike of conventional 11-tube shape and added some random dimensional limits. Constructing a sensible definition of an acceptable bicycle without first drawing a bicycle is surprisingly tricky. You have to start with a human being, and limit the position he can adopt, then define how he may touch the bicycle, and finally create a mathematical envelope to contain all the parts of the bicycle which hold those contact points together. When you think you've got that about right (i.e. it works for all morphologies, and all cycling disciplines, and it doesn't have any loop holes), you get to the hard bit; designing a way of enforcing the regulations in a way which is consistent with the needs of race organisation, international trade agreements etc.
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• #591
As for 3D printing, I am wondering... Does it produce structurally strong pieces (compared to forged metal, for example) ?
It does but with some significant drawbacks. While the grain size and structure can be well controlled. With titanium for example, some electron beam melting methods, such as Arcam, can produce a bulk material with better properties than the wrought equivalent. Assuming you get consistent melting through the layer. However, the major drawback is surface finish, which is generally terrible and a function of the thermal conductivity of the metal. Macro and microscopically extremely rough. While for the most part these rough surfaces can be machined or precision linnished off this can only be performed (at significant cost in both time and money, which can defeat the obtect of rapid prototype manufacturing methods) on external surfaces. So when you have a nice complex structure where material is only placed where it needs to be, if there are surfaces that are internal, enclosed or unreachable it leaves a really poor surface riddled with pits and holes that are excellent crack initiation points. This hugely limits the fatigue life of such a part. This is something most people don't realise or even address but is the reason such parts are not used, in F1 for example, for fatigue critical parts but may be used for components such as the roll hoop, which is highly structural (in the event of a roll-over crash) but not subjected to any fatigue loading during its life.
This surface roughness factor, which can go as deep as 0.5mm or more, can have major implications on achievable component wall thicknesses.tldr: yes and no.
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• #593
didn't know where to put it ... anti porn
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• #594
Another eBike replacement rear wheel thing. This time it's solar powered!
Probably a reep. Whevs.
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• #595
available at a evans near you from jan 2015
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• #597
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• #598
haha hah very true ~!
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• #599
epic skidz
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• #600
The Smart e-bike was saved from the worst excesses of art-school wankers by the discipline of the engineers who actually put it into production, although it's odd that nobody thought at any stage of the process that users might actually want to carry their shopping on it.
For worse:
For better:
wicked,if i needed a vintage nos part that would be great.