Early Bird Base Design

Thu, 19 May 2011

I've been working on the Early Bird model as well as a couple of other projects which I'll tell you about later. Having worked out the bird, the worm and the mechanism it is matter now of fitting it all together.

My initial plan was to fit everything into a box like the one above. I've added triangular box sections to the sides of the legs for rigidity. I planned to extend the legs so that they would go through holes in the top of the box, I could then glue the legs to the sides of the two box sections to hold the bird into place. 

The problem is that the box section is inherently flexible. 

Triangles are good where things need to be rigid. To that end I put together this shape.

The sides are nicely rigid but the centre flexes horribly.

By cutting small holes in the side of the tube sections I was able to add a second, smaller tube section running across the base. Looking good!

With the base and bird complete I could then glue the two together.

This will be a case of function leading form. The box I had originally planned is now gone. I'll suspend the cam follower and worm from below the base. I plan to make the ratchet and cam as a separate unit then join the two together using a couple of vertical beams.