The Quadricycle Build Story

16th February 2010

I've now got a design together which I am fairly happy that I can make work- I'm sure it's probably a bit over-engineered in places, but having not done that much metalwork before I think I'm going to err on the side of caution.

Below are a few screenshots of my initial CAD work.

There's no steering mechanism drawn yet, as I'm still trying to get my head around the geometry of it, and the angle of the seats and exact positions of the bottom brackets will be set once I start building and testing.

The main structure will be made out of 3"x1"x10swg (3.25mm) aluminium tubing.

The lighter grey bracket-ty looking bits are 2"x2"x1/4" aluminium angle.

The rear-wheel supports will also be made from the 2"X2" angle.

View from above/stoker side:


View from above/behind:


View from above/pilot side:


View from above/front:


View from below/pilot's side:


View from below/front. Many of the 2"x2" brackets can be clearly seen:


I intend to bolt the whole thing together, (hence all of the bracketry) as opposed to welding, as I have very limited welding experience and going by what I have read, aluminium welding is not for beginners.

Obviously, the chains are not shown on these drawings, however I'm planning on simply using two rather oversized chains to go straight from the cranks to the cassettes. I did originally start designing with the back wheels pretty much in line with the front ones, then decided all of the extra bits required to make it work would just end up being too complicated & costly!

To give an idea of scale, the wheels in the drawings are 20" rims, with MTB tyres, so round about 60cm in diameter.

Next- 8th March 2010