Exposing the ‘obvious’

Occasionally its nice to have a minor revelation about the design, and today was time for a reasonably major one.

I’ve been building the latest prototype and since it’s actually easier to just make pentagons and half hexagons, that’s what I’ve been doing. This is another perfect example of learning by doing, since although what I’m about to write would appear pretty ‘obvious’ to anyone looking at it, no one has bothered to point it out. Building things in the computer is easy, they fit together and are nice and shiny, but nothing beats getting your hand dirty and when you’re faced with bolting a million parts together you naturally look for some shortcuts.

This isn’t really a shortcut, but pretty important all the same. There is no point designing something that costs a fortune to manufacture, not for a startup anyway, so every manufactured part that doesn’t need a process or tool saves a huge amount of time, in producing them and cost in tooling. My initial idea has always been based around three panels and one part on the edges to hold them together. These four parts need to be very strong and very precise in their manufacture. Any defect in any of them means the sphere doesn’t fit together very well, and a ‘wobbly’ sphere is not good.

Well, he’s the obvious part… why make three panels when I can just make two?

Screenshot 2015-06-01 14.32.57

The half hexagon is just a hexagon cut in two… so joining two together makes… a hexagon. If the panels are made from moulded plastic their size means the tooling for them would probably run more than $20,000 each, so reducing the panels numbers means a massive saving at the start of the project.

Pure hexagons still look a lot cleaner, but at the start of a project when every dollar saved might mean the projects survival $20k in the bank is an amazing revelation. All that’s needed is four more holes in the half hexagon and another two connectors per hexagon, and if these don’t need to be quick release they could be much simpler (although that again adds another part, which we should be trying to avoid :p).

So, again, if anyone has any other ‘obvious’ suggestions please let us know…. 🙂

2 thoughts on “Exposing the ‘obvious’

  1. I’m not that knowledgeable when it comes to practical engineering, but wouldn’t it make the whole thing more stable if you change the connectors to a plus shape (make – to +)? So that shear forces and the like can be mitigated along two axes instead of only one.

Comments are closed.