[Closed] Custom 3D printed frame anyone?

http://bastion-cycles.com

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or just plain old Ti @ 1000gm

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It's pretty, but I think we're still at the stage of using 3D printing so you can say "I've got a 3D printed bike".

How about mass produced threads?

[url= http://singletrackworld.com/wp-content/uploads/2016/05/robot-bike-company-r160-like-nothing-youve-ever-seen/ ]http://singletrackworld.com/wp-content/uploads/2016/05/robot-bike-company-r160-like-nothing-youve-ever-seen/[/url]

[url= http://singletrackworld.com/forum/topic/robot-bike-company-r160-%E2%80%93-like-nothing-you%E2%80%99ve-ever-seen ]http://singletrackworld.com/forum/topic/robot-bike-company-r160-%E2%80%93-like-nothing-you%E2%80%99ve-ever-seen[/url]

[url= http://singletrackworld.com/forum/topic/robot-bike-co-r160 ]http://singletrackworld.com/forum/topic/robot-bike-co-r160[/url]

Pretty sure Starling Cycles talks about using it on his rear triangles at some point.

Indeed ben - personally I don't even really get this need to have custom geometry frames, given the vast majority of people will end up with much the same as they could have bought off the shelf anyway.

Hullo, Joe from Starling Cycles. I am indeed thinking about using additive manufacturing (AM) for some swingarm parts.

I have some experience from a previous research job I had, particularly into structural optimisation. I'm particularly interested in reducing weight and part count for my yoke region. The idea is to first produce the optimised structure, then I'll get some plastic prototypes made to see how it works with a real swingarm manufacture.

Then I'll look into cost of production. It may be it has to sit on the shelf until the cost of 3D printing comes down, but then I'll be ready to go quickly. Being built in a shed, doesn't mean it can't be high tech! The opportunities offered by AM are pretty good.

Personally I've spent ten years working in composites, and I think AM has a better future ahead of it.

Interesting comment Joe. What about the future for completely machine-made composites? (That is, with fibres running from end to end and so on.) Tiny robots weaving them perhaps? Genetically modified spiders spinning their webs in a co-ordinated way?

we're working on that...

(it'll be a while till we have to recruit the spiders though)

A friend of mine had quite a few sets of steel 3D printed lugs made, the cost wasn't as high as I thought they would be and he figured that a lot of the cost was eaten up by simplified manufacture later down the line.

I do a lot of design work for 3D printing and the vast majority of it never really goes anywhere as the client either wants something for a posh press realise and nothing more or they soon realise that 3D printing still has limitations and you cant actually "print anything you want".

Personally I've spent ten years working in composites

Where ? , this is the bit I really find interesting, what people bring from other industriess, we used to see a lot of this at Ansys

Ten years working for suppliers for Airbus, mostly in composite research. More on the stress analysis, and concept development side rather than materials and manufacturing.

I just need to time to get the development going for my frames.

Question

Wouldn't a proper stress analysis, of load paths, lead to a printed frame looking much more like this

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This is not a frame, obviously, but I hope you get the point (geodesic esque)

Isn't anything else just replacing tubes with tubes ?

Do you think it'll be cheaper if I just want the CAD file? 😆

Yes totally. The optimisation programs result in very organic shapes. The issues comes with trying to turn this into a CAD file that the 3D printer can use. Also the interfaces, bolted regions etc, tend to need to follow standard design guidleines.

When I was working on AM for a wingbox rib demonstrator, the optimisation software gave some beautiful (in a HR Geiger type way) structures. But turning them into something that could be drawn in CAD and subsequently manufactured with sensible interfaces (that needed to be machined for tolerance issues), meant we moved away from this. Although it did look more organic than a normal design.

With bikes there the additional issue of it being organic and aesthetic. If you don't like Geiger, you may not like the look of it. The Robot bike just uses the AM to allow differnet lugs to be used. No structural optimisation, in the computer generated sense, has been used.

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Taken from [url= http://pencerw.com/feed/2016/6/18/another-iteration-of-my-bike-stem ]here[/url], apparently the author indends to have it printed (and presumably, tested, like his earlier [url= http://pencerw.com/feed/2015/8/6/3d-printing-titanium-learning-to-learn-from-success ]seatmast topper[/url] and [url= http://pencerw.com/feed/2016/6/21/seatposts-tested ]seatpost[/url])

That'll be a bugger to get clean.

My son & I had a fascinating chat with the guy from Miranda Pro whilst at Bespoked. According to him, cost wise, Ti was cheaper to print than steel as although the Ti material was more costly, it printed quicker than steel and thus machine time was less with Ti. Machine run time was the costly factor.

He said to my son, that the 3D print future belonged to his lifetime & reckoned that every town will one day, have a 3D print shop with the ability to print any metal that can be atomized.

Oooh I like that stem

The thing about structural optimisation is, that it works only in relation to the input FEA mesh that it's given. On a (relatively) large structure or available space such as a bike frame, the individual element size required to reveal a geodesic structure in 3D space would be tiny, thus the total amount of elements required to map the space would be enormous.

That stem above is just a lattice overlayed on topology optimisation result; I'd barely class it as optimised and wouldn't use one...ever.