OK, I've been kicking around some ideas. The basic idea is presented here.
As you can see it's really not that complicated (mechanically at least). For this project I'm going to try to stick with 2 principles. Keep it simple and make it cheap! My intention is to build a functional 3d printer within my almost non-existent budget. Later, if successful and as finances allow, I can upgrade components to achieve higher precision.
I can break this project down into 3 parts:
I'm confident that I can build the hardware portion of the printer. It's actually much less complex than the inkjet/powder printer. In fact, I'm going to harvest much of what I need from that progect. I'm working on a design sketch which i'll post soon.
The software... well, I would love to be able to purchase comercial RP software (Magics 15) but there is no way that will ever happen. I think it's considered the gold standard because you need a pile of gold to buy it! It seems that any software that does everything I'll need (including generating support structures) falls into the catagory of "If you have to ask you can't afford it". Since I don't have access to a pile of gold, I'm going to make due with what I can afford (free) and what I already have (Powerpoint). I'll have to make due with manually adding support structures. I'm really hoping that the open source community will develop something for that.
Lastly, the chemistry. I'll worry about that after I get the hardware working. I see this as being alot like the ink/toner of 2d printers. The real money is in the consumables.
Now to sketch up some designs and start collecting materials.