How I built a carbon bike frame at home (and a bamboo frame too)

Step 2 Making the core

After I have built the frame jig and all metal parts were secured in the jig, I began to make the frame core.

I had polystyrene foam rods of the necessary diameters, made simply by using hot wire foam cutter. The cross sections of the main rods was circular, the chain stay and the seat stay were elliptical. I have wrapped these rods with one light layer of fiberglass to increase their rigidity.

In this picture you can see the aluminum parts in their exact position. The polystyrene top tube and down tube is already bonded with carved small pieces of polystyrene for the next sanding. In the front of the picture on the ground the chain stay was being prepared for sanding (to achieve proper shape) and bonding.

Comments

[DarkShadowDemon]

Also could you put up the dimensions of the jig and measurements for the metal parts placement?

[DarkShadowDemon]

Hey, what kind of glue did you use to connect the polystyrene foam together?

[Marsh]

 That is one damn fine jig setup!

[paul591]

Hello! Which way did you cut the foam for the tubes? Did you cut them to be long rectangles first then sand them down to the correct elipse?

[OneBadBird]

How did you make the polystyrene rods exactly?

[Brano]

I made them using simple hot-wire foam cutter and the templates of the tubes cross-sections.
Check http://www.instructables.com/id/Hot-wire-foam-cutter/ , http://www.instructables.com/id/Make-a-CNC-Hot-Wire-Foam-Cutter-from-parts-availab/ , http://www.instructables.com/id/Hot-Wire-Foamcutter-Battery-Powered/