A Bike is Born

I built a bike frame this weekend, I build it using bamboo and hemp with some epoxy resin and a few metal bits. Here are a few pictures of the stages of construction

It all started with a jig that holds the metal head tube and the bottom bracket

We then selected just the right bits of bamboo

Measured them up against the jig to ensure they were just right. I’d selected a few spares as well, just in case I was visited by the catastrophe fairy

Then the bamboo had to be cut to fit round the metal bits using a viscous cutting tool and an angle measuring thing (it has a name, I don’t know it)

The masking tape was there to keep splinters to a minimum, splinters are painful.

The hole is then cut at the correct angle to fit the tube. This is repeated for all the tubes…

They can then be put into place on the jig to for the first triangle. A blob of epoxy holds the tubs in place but the tape holds them in place until the epoxy is dry. The cup of tea in the corner is a vital lubricant for the novice bike builder.

The dropouts are then fixed into position on the jig…

and slots cut into the chain stays and seat stays so that they fit into the dropouts.

The chain stays are then fitted into place and fixed using epoxy

As are the seat stays.

It now looks like a frame but it doesn’t look like it will stay together in a strong wind.

The frame is held together with hemp strips that are soaked in epoxy resin and then wrapped around the tubes

Like this.

Once the joint is formed it is wrapped in electrical tape whilst the epoxy sets

Initially the epoxy gets warm as the reaction hardens it, then it cools. Once it is cool the electrical tape can be removed

And there we have it, one bike frame born from a pile of bamboo, some hemp and a few metal bits. It needs to be finished and lacquered to become a proper frame and then equipped to become a real bike but that will have to wait a while.

This was all done on a weekend course with the Bamboo Bicycle Club