Bicycle Frame Builder

[you14]

Hi all! I've been looking into building carbon fiber bike frames, and Sketchup looks like the perfect tool for me.

The process goes something like this:

1. Get bike measurements.
2. Model in Sketchup and export to dxf.
3. Bring dxf to cnc cutter and have foam core cut.
4. Wrap foam core in carbon fiber.
5. Pour acetone in frame do dissolve foam.

So I've been playing with Sketchup, and a few questions arise, but I'll just start with one for now.

For the tubing, how do I start with one shape (say, a circle) and end the tube another shape (a rectangle, or oval)? This is important for intersection of the down tube and the bottom bracket (Where the pedals are).

I'm sure I'll have more questions along the way, but thanks in advance for any help.

[you14]

Wow...That blend plugin is exactly what I need. Now I have to start playing around with various shapes. Customers like unique. When I get something, I'll post an image.

Thanks a bunch!

[numbthumb]

Hi, you14!
For such round-to-square transitions you can use Krill´s blend plugin or TIG´s Extrude Edges by Rails.
For bike frames, plugins like TubeAlongPath or PipeAlongPath may come in handy, as well as SU Follow Me tool.

http://forums.sketchucation.com/viewtopic.php?f=323&t=21134&st=0&sk=t&sd=a&start=45

http://forums.sketchucation.com/viewtopic.php?p=201286#p201286

Search the forums for additional info on plugins.
Cheers!

[you14]

Alright, I've successfully designed a top tube that starts as a rectangle, then blends to an oval. So that's taken care of.

Now I'm having trouble with the tube miters. All I need to do is put a half circle on the bottom of the tube, and push it, but of course, I can't on a curved surface, and the push/pull plugin I got (sorry, I don't remember the name of the author) is just messy, and inaccurate for something that needs a smooth miter.

I tried making a square tube, and pushing the half circle out, then taking the four corners off to make a circle, but the push/pull limits the offset to the intersection of the circle. (I've included a screenshot of both the miter attempt with the push/pull on curved surfaces, and the square with circle idea)

Thanks folks, I've been trying for a long time now with no success, so I'm hoping someone has done this.

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[Rich O Brien]

Is this what you mean?

Tube Mitre.skp

[you14]

@unknownuser said:

Is this what you mean?

[attachment=0:2dothqcn]<!-- ia0 -->Tube Mitre.skp<!-- ia0 -->[/attachment:2dothqcn]

AAARRRRGGGGHHHHH!!!!!!!!! How could it be so EASY???!!!!!

That is frustrating to work on it for HOURS, not getting anywhere, then do it in 45 seconds.

Good news is, I know how to do it now. And thats all that matters. Thank you rclub24 for helping me stay sane.

Well, as close to sane as I'll ever get.