3D Printing

World's first 3D-printed titanium bicycle frame could lead to cheaper, lighter bikes

World's first 3D-printed titan...
The MX-6 Evo mountain bike, sporting its 3D-printed titanium frame
The MX-6 Evo mountain bike, sporting its 3D-printed titanium frame
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The components of the seatpost bracket were printed together on one build platform
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The components of the seatpost bracket were printed together on one build platform
The steps in the MX-6 Evo's build process
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The steps in the MX-6 Evo's build process
The MX-6 Evo mountain bike, sporting its 3D-printed titanium frame
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The MX-6 Evo mountain bike, sporting its 3D-printed titanium frame
The MX-6 Evo mountain bike, sporting its 3D-printed titanium frame
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The MX-6 Evo mountain bike, sporting its 3D-printed titanium frame
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When it comes to a high strength-to-weight ratio, titanium is just about the best material out there for manufacturing bicycle frames. Unfortunately, those frames are also quite expensive. They could be about to come down in price, however – two British companies recently teamed up to create the world's first 3D-printed titanium bike frame.

Renishaw, an additive manufacturing firm, joined forces with Empire Cycles to build the one-off titanium MX-6 Evo mountain bike. Empire already offers a production aluminum version of the MX-6.

The frame was built using an AM250 laser melting machine manufactured by Renishaw. In the build process, a high-power ytterbium fibre laser was used to selectively fuse together particles of a titanium alloy powder. Layers of those fused-together particles were built up one upon the other, to form the finished sections of the frame. Those sections were then bonded together using an adhesive.

The components of the seatpost bracket were printed together on one build platform
The components of the seatpost bracket were printed together on one build platform

Because titanium has a higher density than aluminum, less of it had to be used if Empire wanted a finished bike that was lighter than the stock model. To make that happen, topological optimization software was used – it structurally assessed computer models of each part of the frame, and determined where less material could be used without negatively affecting strength.

As a result, at a total of 1,400 grams (3 lb), the finished Evo frame weighs 33 percent less than its aluminum counterpart. When its seatpost bracket was tested, it exceeded the EN 14766 mountain bike strength standard by six times. The strength of the frame as a whole is still being tested.

So, how could this project lead to cheaper titanium frames? For one thing, in the laser melting process, there's no waste – all of the titanium alloy powder that isn't fused to make one frame can be reused in another, plus the topological optimization process ensures that less of it is needed in the first place. Additionally, no special machining has to be created or set up for specific frame designs, which would be the case with cast metal.

It should also be relatively simple to tweak frame designs as needed, or to add custom features to individual frames. And finally, it shouldn't be any more difficult to create components with complex shapes than those that are relatively basic.

The European Aeronautic Defence and Space Company (EADS) has previously created a 3D-printed bicycle frame, although it was made from nylon.

Source: Renishaw via Stuff

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22 comments
Slowburn
If you can laser weld powder into solid mettle why cant you laser weld two pieces of solid mettle together even if you need a little powder to help?
Danny Rose
Frame 1.4Kg!
Gadgeteer
Slowburn, Direct metal laser sintering fuses a thin layer of powder at a time. Each layer is in the order of microns thick. It doesn't produce enough energy to penetrate deep into a part, which would also risk heat distortion. If you want to weld titanium parts, you'll have to rely on good, old fashioned TIG welding, which is too risky with a frame like this that's been lightened as much as possible.
Mark Penver
I suggest the Author reads about laser sintering titanium and the costs. time and size all need to be taken into consideration. That's probably a good £40k frame they've built there - if not more. http://www.core77.com/blog/exclusive/exclusive_photos_making-of_the_queens_baton_for_the_xx_commonwealth_designed_by_4c_design_ltd_25735.asp
Robert Craven
Be careful on you phrasing of cause and effect. Lead is also denser than aluminum but it wouldn't make a great bike frame. Titanium is stronger than aluminum might be a better phrase.
Bruce H. Anderson
The other thing to consider is bed size on the 3D printer. To do an entire frame in one piece would need a bed at least one yard or meter square. The picture looks like several parts were made concurrenlty on a bed that might be 8"x8". Still, quite the accomplishment. And like the 1911 recently done elsewhere, quite the price tag I bet.
Brainfarth
Given the size of the bed that would be needed for printing and the inefficiencies that would go along with printing a whole frame, pieces are the key. And even though I have welded Ti quite a bit, the socketed route is the way to go. You only have to glue the pieces together. Where as the TIG welding of them would require a special jig, argon purging of the frame, specialized welding cups and skilled labor. And maybe the first couple bikes could cost in the 10's of thousands to help recoup R&D, but with an efficient crew that would keep the flow of parts flowing through their million dollar printer, I could see the prices dropping to a somewhat reasonable level.
James McAllister
Although the article says there is no wast, It appears to me that there is some wasted material. The base and the "sprue" sections in the photo appear to be titanium which would be separated and become scrap. As far as joining the pieces, I believe titanium can be brazed, perhaps with a titanium/silver alloy in a vacuum furnace. That would result in an extremely durable final assembly.
moreover
Brainfarth has it right: creating the connecting pieces is where 3d printing works best. Once you have those joints it's easy to finish the bike with mass produced tubes.
PerryRObray
Be interesting to see case studies in extreme environments. Asphalt areas in the southwest U.S.A. apparently get around 130 degrees Fahrenheit. The far north gets very cold too. Not to mention stress testing in extreme freestyle, downhill mtn biking, ect.... A very competent testing evaluation should be very interesting.