Re: [CAD_CAM_EDM_DRO] Making a rapid prototyper

So what is the philosophy of this project? To develop the design completely
from scratch? To build a completed machine then replace components with
self-manufactured ones? Complete bootstrap from scratch?

A couple of comments, though.

1. If you use an melt extrusion process, you'll always have issues with
resolution. You'll chase the resolution by making finer and finer heads,
each more difficult to build than the previous. However, you do have a 3D
stage built into the machine and a finish pass against a tool would get you
as much resolution as your positioning system could deliver. You could make
cutting tools out of a ceramic and drive them with one of your steppers.

2. Your project seems heavy on the bootstrap philosophy. It might make
better progress if you incorporate elements that are intended to be replaced
by bootstrap parts later. You already have motors and die silicon and that's
a long way off to make yourself.

3. If you're looking at motor technologies to replace your steppers, there's
a branch of RC airplane, um, enthusiasts building high torque motors from
old CDROM spindle laminations. The brushless DC controller isn't all that
more complicated than a stepper controller, and if you use a high resolution
pwm to drive them, they'd make pretty effective ac servos. (Ok I take that
back about the motors. You still have a bearing problem though.)

4. There's a lot of progress in conductive polymer inks. Several groups
(including one that I visited at the University of Michigan) are working
toward making semiconductor circuits with an ink printing process like in an
inkjet printer. Being able to build a nozzle like one in an inkjet might be
possible with a cutting tool.

Well now I want one.

On 8/2/06, Sebastien Bailard <Sebastien.Bailard@...> wrote:
>
> On Tuesday 01 August 2006 12:28, Alan Marconett wrote:
> > HI Sebastien,
> >
> > I found and mentioned the RepRap project on this list just last week! A
> > bit after the bevy of posts on self-replication of a few weeks ago.
> >
> I ran across your post after sending out my email, I hadn't finished
> reading
> the backlog.
>
>


[Non-text portions of this message have been removed]