3D printing -> totally custom Ti stems

[wallymann]

i just ran across this from last year, but it makes total sense for getting that perfect fit: 3D printed stems in Ti!!! i know there are lots of builders that make custom stems, but honestly a TIG'd or fillet-brazed stem aesthetic just doesnt look right with most modern bikes.

seriously, this is awesome. i have literally 15 extra stems in my service-course that i've accumulated as i've dialed in position on a range of bikes thru the years. instead of searching high-and-low for some mythical stem to to minimize spacers and/or get that perfect position, just punch in the desired reach/angle/diameters and maybe some other options like # of bolts, clamp height, finish, etc. submit your order and the mfg can print the perfect stem for your needs...voila!

i dont know that the fancy lattice-structure is necessary, but hey -- that could be an option too -- it works for holland and their exo-grid frames!

http://brimages.bikeboardmedia.netdna-cdn.com/wp-content/uploads/2015/11/Van-Nicholas-3D-printed-titanium-mesh-bicycle-stem01-600x400.jpg

[54ny77]

that is very cool but there's no friggin' way i would entrust my family jewels to that vs. tried & true forged alu stuff from any major manufacturer. and yes, i know there's failures there too, but am hoping statistical anomalies are favorable on my side....

[tumbler]

i just ran across this from last year, but it makes total sense for getting that perfect fit: 3D printed stems in Ti!!! i know there are lots of builders that make custom stems, but honestly a TIG'd or fillet-brazed stem aesthetic just doesnt look right with most modern bikes.


Aesthetics are obviously personal preference, but I would prefer a traditional stem over this on just about any bike, modern or traditional. This just doesn't look right.

I've never understood the draw of 3D printing beyond making small plastic parts or toys. Are they actually able to print metal that compares strength-wise to forged or CNC'd parts? Maybe I don't understand the process, it just seems like that would be hard to do when you are assembling something by printing a million tiny dots of it.

[ergott]

I could see them printing that stem out and doing a carbon wrap around it for the finished product. Not sure if that's viable or not.

[wallymann]

that is very cool but there's no friggin' way i would entrust my family jewels to that vs. tried & true forged alu stuff from any major manufacturer. and yes, i know there's failures there too, but am hoping statistical anomalies are favorable on my side....

there's nothing inherently wrong with 3D printing a structural member in high-stress applications where safety and structural integrity is a primary consideration.

3D printed Ti is successfully used in cryogenically fueled rocket engines, gas-turbine engines, and other structural aerospace applications. we're talking temperature swings from hundreds of degrees below zero to thousands of degress above zero and pressures/stresses astronomically higher than anyone human would expose a bicycle stem to...it all comes down to proper engineering and design.

I could see them printing that stem out and doing a carbon wrap around it for the finished product. Not sure if that's viable or not.

i think the latticework is just to showcase the process. in reality, i think it'd be way better to design with a solid surface. lattice work is just showing off their skills, like these guys:
http://1.bp.blogspot.com/-6X_5ymYkY0k/UWwxRYyvcSI/AAAAAAAAYxM/5R-5sR0p-BM/s1600/store-ascend-frame.jpg

holland has already shown that a combined Ti/CF structure can work with their exo-grid tubes!
http://hollandcycles.com/wp-content/uploads/2014/02/c10.jpg
http://theformed.com/wp-content/uploads/2012/12/Screen-Shot-2012-12-18-at-11.38.09-1024x563.png

[Tickdoc]

21st century drillium. Kewl.

[ultraman6970]

Those stems look awesome, do you think they will work the same way as a normal one or they will snap??

[berserk87]

I wonder if the wind would whistle through those stems when riding.

[KidWok]

Makes a nice cheese grater too! Looks cool...would also wonder if it holds up as well as forged parts.

Tai

[OtayBW]

there's nothing inherently wrong with 3D printing a structural member in high-stress applications where safety and structural integrity is a primary consideration. I think it is material/context-dependent. I don't know about 3D printed metals, but I can say that some of the folks in the group I work with are trying to develop/improve 3D printed concrete structures for everything from pre-cast members to complete low-cost housing units. One of the big factors is adhesion/cohesion between printed layers and overall compressive/flexural strength, etc. It's a non-trivial consideration - at least in this application.

[RFC]

If I'm correct, the term "3D Printing" encompasses a variety of fabrication techniques, i.e.,

-- Adding material to create an object.

-- Transforming material from one state to another -- liquid plastic to solid.

-- Removing material from a larger block.

What they have in common is that the process is computer driven.

I am assuming that these stems are fabricated with the third technique, the removal of material.

[OtayBW]

If I'm correct, the term "3D Printing" encompasses a variety of fabrication techniques, i.e.,

-- Adding material to create an object.

-- Transforming material from one state to another -- liquid plastic to solid.

-- Removing material from a larger block.

What they have in common is that the process is computer driven.

I am assuming that these stems are fabricated with the third technique, the removal of material.
I view it as largely depositional/additive fabrication vs. machining, but either way, I would be concerned about strength etc. considerations where appropriate.

[RFC]

I view it as largely depositional/additive fabrication vs. machining.

I have seen the liquid to solid fabrication is action. The liquid plastic is created to solidify when exposed to a particular light frequency. Basically, it looks like an aquarium full of liquid plastic with a computer controlled pin point light that continues to follow the planned shape. As the liquid solidifies, the liquid level is reduced to the next layer, and so forth

Often used to create toy prototypes, etc.

And I've seen the material removal method. Used by dentists to create replacement teeth.

3D printing has been around for a couple of decades. What has changed in recent years is the sophistication of the process to create much more complex, multipart objects and the accessibility of the process to specialty custom manufacturers and home hobbyists.

[drewellison]

I'd like a 3D printed stem with the following features ...
1. bottle cap opener opening on one side.
2. a little compartment hatch on the other so you can store your emergency tools inside.
3. built in bell or a mounting system for a spur bell.

Damn, I should be in product development. :bike:

[makoti]

Do you think they whistle in the wind? That would be very annoying.

[berserk87]

Do you think they whistle in the wind? That would be very annoying.

I don't know, really. I was just funnin' around on that.

[sandyrs]

I'd like a 3D printed stem with the following features ...
1. bottle cap opener opening on one side.
2. a little compartment hatch on the other so you can store your emergency tools inside.
3. built in bell or a mounting system for a spur bell.

Damn, I should be in product development. :bike:

Storage for a nip of Fireball would be ideal.

[wallymann]

I think it is material/context-dependent. I don't know about 3D printed metals, but I can say that some of the folks in the group I work with are trying to develop/improve 3D printed concrete structures for everything from pre-cast members to complete low-cost housing units. One of the big factors is adhesion/cohesion between printed layers and overall compressive/flexural strength, etc. It's a non-trivial consideration - at least in this application.

material dependent, yes. non-trivial, yes.

but like i said, 3D printing using laser-sintered titanium and nickel alloys is used in rocket engines, jet engines, aerodynamic structures. you know...where safety-of-flight is all-important and things blow up catastrophically if something fails. i doubt anyone would be consider using 3D printed concrete or plastic for structural bike parts, that would be asinine.

[oldpotatoe]

https://www.youtube.com/watch?v=UO7RNReR9Ys

[wallymann]

"That was only a prototype. We had never plans to put this in production. We don't bring it in production."