Re: [CAD_CAM_EDM_DRO] Re: RoboFac / Stewart-Gough Platform / Hexapod Milling Machine

Wayne C. Gramlich wrote:

>Whenever I read one of these CNC articles in a magazine,
>the first question I ask is "How accurate is the machine?".
>To date, the Robofac article has not discussed accuracy.
>For the amount of money he spent building the thing, I
>suspect he could have purchased a Sherline/Taig table top
>unit and done a quite straight forward CNC conversion.
>Again, it is hard to tell because he does not discuss
>prices to any level of detail.
>
>

Any suggestions for measuring accuracy?

Does Sherline or Taig make a 5 axis machine? I suspect my hexapod has a
larger work envelope.

I have spent less than $1000 on RoboFac. I didn't include a price list,
as many of the parts are scrounged, including the controlling computer.

Some of the more expensive parts that I paid for were:
metal for the frame
sheet metal bed
stepper controllers
stepper motors
anti backlash acme nuts
motor power supply
router

>I don't want to come down too hard on his work, since
>it really is quite a challenging project. But in the
>end, the question is whether or not he is able to build
>useful parts or not with his creation. So far, I have
>my doubts.
>

It's not for everyone. I have done some useful work with RoboFac,
including milling aluminum. Have a look at the CNCZone thread:
http://www.cnczone.com/forums/showthread.php?t=7467&page=4