Not sure the wheel cutout form you have is necessary. It would not sit close to the wheel as is.

As for the strength of material, depends on how heavy you plan on loading it and the thickness of material.

Also, how do you plan on keeping it from slipping on the seatpost. Friction force? Probably would he ok if you got the dimensions just right. Likely some modification will be necessary after printed to get it just right.

As for aero, who knows. It's in an area that sees a fair bit of turbulent air anyways.

Also, consider width. As I'm designing a p3 bb bento I have found it needs to be decently wide to fit what you need. Internal width needs to fit a co2 cartridge.

I did realize the wheel cutout. And then went to bed.

As for keeping it on from sliding on the seat post, I was thinking friction fit, with a layer of electrical tape on the seat post first. If that didn't grab it really well, I would wrap 2-3 layers of tape just below the mount, so it couldn't slide lower.

And loading it, I would fit a tube, tire lever, co2+nozzle.

As for internal width, good point. I'll likely spend today revising it.

It's a good start. Just wanted to provide some things to think about.

Aero, all any body will be able to do is guess.

I would guess if it would help clean up frame to he more bear in some way, it would be helpful

Yes, and thank you. If I had my own printer, I could just throw several together and see what works best. My school has a printer, but I don't go back until Sept. I will probably find someone in my area who prints for people.

PS: is your bb storage box for the NP3?

Is that a student version of solidworks?

If so, you should have access to the Flow Simulation modules :-)

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It is indeed :) I've only played around with that a little; I'll try more today.

I've only taken one year of engineering at my school and that was two years ago so I'm a bit out of practice :D

Yes it is.

And I have a 3D printer. But not really practical if you plan to itterate.

ETA: Also, No reason to make it in pieces unless you plane to add and remove the box on a regular basis.

The only problem I envision is if I make it in one piece it starts getting close or larger to many 3D printers max size.

True. Plus the ability to remove is always nice if you want.

The larger the part the more $$ it costs (disproportionately). Also, weight is a concern as plastic is light but that much plastic will add significant weight/material (which in turn will increase build times and in turn cost more $$.

I've been messing around with designing a draft box also for my Felt bike too. I've found that my build size for the box alone is coming in at almost $93 bucks in its current iteration (still haven't designed mounting points or a lid yet). The footprint of my box is 15x15.5x4.5 (all in cm). Shape is based on an strut airfoil for mine to be somewhat aero. I'll probably use velcro straps and put some slots in mine to save costs and design effort though. But, I still have to finish the design first.

Currently, I am using Shapeways to cost things out for my design.

What are the dimensions of the finished part?

I've got a 3D printer with a 10"x10"x10" build volume.

-moyes

It looks fun, but I suspect there would be more gained by just strapping the c02, tube and lever invisibly under the seat.

What printer?

Right now it comes in at 4.75" x 8" x 1.25".
Many printers I've seen have an 8x8x8 build surface.

I've added a decent amount of width after I went out and measured a can of pitstop. It looks even less aero now (I'll try and figure out data later) and weight is at .99lbs. If aero looks poor enough I'll make this my second priority and see if I can make a bb box for my P3 classic. I'm thinking attach to bottle bolts and hug the seat tube. Well see

This right up my alley..I just finished up high school (headed to UVA Mech-E in the fall), and my senior thesis project for honors was my own design of an aero-road helmet (used AutoCad, 3D printer, and small wind-tunnel). Saved 9W at 30mph. Was mentored along the way by the guys at Specialized.

The 3D printer you'll likely have access to will probably not be capable of printing a surface with a low CdA. No matter what level of definition you set it to. Remember, it's not injection-mold plastic. Depending on what printer you have, it may lay down the material in a hollow honeycomb pattern. I know MakerBot does this. This limits your ability to sand down to a more ideal surface when refining after the print. Sand too much, expose the honeycomb pockets, and you've got air pockets on an "aero" design. Not good!

Your questions:
1) It won't be as fast as riding without it, most likely. There are a few small improvements you could make. Taper the edges a bit, try to achieve more of an airfoil shape. Wheel cutout probably not necessary. I would look at some other designs out there and take the bits you see as necessary. Also, you should have access to flow modeling in the student version of Solidworks. Test, refine, test, refine, test, etc.

2) I talked about materials above a little bit, mostly their shortfalls. I don't see strength of the material as an issue. My printed scale model helmet was strong enough to be blown at 50mph into the back of a wind tunnel with a metal grate (woops) and remain completely intact. How much you load it up could impact it, slightly, but that plastic is pretty strong.

3) A few final suggestions:
- Those pins could fall out at speed, unless you've got a lock-in mechanism that the picture doesn't show.
- The 3d printer I had access to (typical small makerbot) only had the ability to print something 4in in length. Make sure you know your size limit, and be aware of the cost (usually charged per in^3). If you do this through a school printer, it could be free. Some libraries as well.
- If you use Makerbot, there is a weird conversion factor in going from your software's measurements to Makerware (or at least, this was the case for AutoCad).
-Make sure that it will sit flush to the seatpost without damaging it, but also without moving around. Maybe increase the size of the opening by 1mm. Use some sort of lubricant (O-Ring lube for pools is good) to fill the space and ensure that it sits flush without damage.

Overall, cool project, and it's great to see some other younger people looking into the engineering behind cycling equipment. PM me if you've got any questions, and there are likely much more qualified people than me to answer your questions here. I thought I'd chime in as I just finished a very similar project.

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"Don't you have to go be stupid somewhere else?"..."Not until 4!"

One suggestion for surface finish. Take some acetone and rub it on the finished part....it will dissolve the material some and smooth out the fine ridges created by the 3d printing process. It goes a long way to making a better surface, but be sure to thoroughly rinse it off when you are done or it will continue eating away at the part.

Makerfarm 10" i3v Prusa

Pretty nice for the price.

-moyes

Only applicable with ABS. ABS is soluble in acetone. Process is called cold vapor smoothing. Pretty easy to do.

PLA isn't soluble by acetone. There are some techniques people are playing with but nothing super easy from what I've seen.

I regularly print in both. ABS tends to have issues with warping for various reasons. PLA, not so much.

-moyes

I had contemplated printing a tool holder for a friends P3 that has the wonderful mounting screw above the bottom bracket

Since i only have the ability to print PLA which would not be thermally stable enough for this... i haven't really progressed past the "gee wouldn't it be neat if i could print something other than parts for my printer" stage.

I was almost contemplating printing positive and negative mold and laying either fiberglass (which I've worked with) or carbon fiber (which i have not).

Would plastic be better than fiberglass/CF?

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I do the same thing as them, just slower

You are absolutely correct. I have only used the Stratasys Dimension line which uses ABS.

A few things to consider:

There are some easy ways to dramatically smooth (post printing) ABS parts. So much that they will look nearly like injection molded parts. So, if the shapes are right (and this is a big 'if'), surface finish will not be an issue for aero drag.

And kind of off-topic, 3D printing is still not viable for mass production. Yet.

Until this comes out, then the revolution will really begin in earnest. Get ready, because nothing will be the same.
https://www.youtube.com/watch?v=ihR9SX7dgRo

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Advanced Aero TopTube Storage for Road, Gravel, & Tri...ZeroSlip & Direct-mount, made in the USA.
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I didn't have much of a choice of materials with printing, due to a super low budget. It was essentially the school saying, this is what we have, you can use it if you want.

Given the choice, I would go with carbon. Super light, more than strong enough for the task at hand, and we're triathletes so carbon is always the first choice.

Plastic would likely be cheaper (I'm not sure) and you'd have more opportunities to print it and refine it.

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"Don't you have to go be stupid somewhere else?"..."Not until 4!"

That looks like a simple enough part to make with a sculptable plastic and flexible sheets for the larger hollow regions.