[Coco] [Color Computer] [coco] Coco CNC

[altair8800c]

I sent a correction.

 It should have been $2,000,000.....

 -Neil







--- In ColorComputer at yahoogroups.com, Gene Heskett <gene.heskett at ...>
wrote:
>
> On Tuesday 13 February 2007, altair8800c wrote:
> >Charlie,
> >
> > Some huge Okuma's out there with 6+ pallet changers. These are
> >$2,000,000,000+ machines. Very neat to see run.
> >
> 2 Billion Dollars?  Let's just say that is a lot of money.
> 
> > -Neil
> >
> >--- In ColorComputer at yahoogroups.com, "Charlie" <chazbeenhad@> wrote:
> >> Hello! 600K a pop? Wow, what types of machines are they?
> >>
> >> I'm a CNC technical leadman for some 16+ years now. My career has
> >
> >mostly been working
> >
> >> with English and American built Cincinnati CNC mills. Mostly Arrows
> >
> >and Lancers.
> >
> >> -Charlie
> >>
> >>
> >>   ----- Original Message -----
> >>   From: George's Coco Address
> >>   To: ColorComputer at yahoogroups.com
> >>   Sent: Monday, February 12, 2007 12:55 AM
> >>   Subject: [Color Computer] [coco] Coco CNC
> >>
> >>
> >>   Okay!
> >>
> >>   I've been working on my Coco powered "Tiny CNC" machine this
> >> weekend.
> >>
> >>   Whew!
> >>
> >>   What a task! I discovered that the axis designations were all
> >
> >messed up.
> >
> >>   (You learn a LOT when working in a machine shop)
> >>
> >>   All three were wrong. X, Y and Z were wrong. So I renamed them and
> >
> >in the
> >
> >>   process, I lost the driver(B09 driver) for the REAL Y axis.
> >>
> >>   No problem, I thought. Just rename the X or Z axis driver. Well,
> >
> >it didn't
> >
> >>   work. After two days, I discover several problem with my hardware
> >
> >that
> >
> >>   proved that the port for the Y axis was wired incorrectly, the
> >
> >cable that
> >
> >>   connected it was also wired incorectly and the software to correct
> >
> >this
> >
> >>   error is now lost.
> >>
> >>   No matter about the software. I repaired my mistakes with the
> >
> >hardware and
> >
> >>   now the software to drive the servos works correctly. I can swap
> >
> >the cables
> >
> >>   to each of the servos and it works correctly.
> >>
> >>   Since I've been working at a machine shop, I was forced to buy some
> >>   precision instruments such as a dial caliper. My old vernier
> >
> >caliper was not
> >
> >>   acceptable at work.
> >>
> >>   Hmm. I really can't see any accuracy difference except for the
> >
> >fact that
> >
> >>   the dial is easier to read.
> >>
> >>   Anyway..... Math always works......
> >>
> >>   All three lead screws are 32 TPI. The three servos are 200 steps
> >
> >per inch.
> >
> >>   Doing the math, this comes to 6400 steps per inch, or precision to
> >>   .00015625.
> >>
> >>   Not bad, but not as good as what I work with at my job.
> >>
> >>   I've learned that offsets and HOME are important. (I did have
> >> trouble figuring into this on my coco)
> >>
> >>   FINDING HOME:
> >>   Originally and even now, I use brute force to drive the axis into a
> >>   mechanical stop. The stepping motor would stall there and hum
> >
> >until the
> >
> >>   software stopped driving it. At that time, I set the software to
> >
> >assume it
> >
> >>   was HOME. Actually, it works! However, it isn't elegant. So I'll
> >
> >add some
> >
> >>   micro switches to the sytem to fix this. Besides, I can move that
> >
> >switch to
> >
> >>   a more convenient place for each project.
> >>   My coco takes a long time to step these motors to where they are
> >
> >supposed
> >
> >>   to be. Basic09 is a lot faster than RS Basic, but it doesn't hold
> >
> >a candle
> >
> >>   to ML. .....Someday, maybe!
> >>
> >>   I envy you folks that can "whip up an ML program".
> >>
> >>   So far, I can move each of the three axis from home to the limit
> >
> >and back
> >
> >>   and my dial indicator reports a return of exactly zero. This
> >
> >implies that my
> >
> >>   stepping motors, power transistors, software and math are working
> >
> >correctly.
> >
> >>   The only problem is finding home. The micro switches will take
> >
> >care of
> >
> >>   this.
> >>
> >>   Backlash on each of the three axis are different. The Y axis is
> >
> >only about
> >
> >>   two steps on the stepping motor. This is incredible!. However, I
> >> took extreme care to minimize backlash when building this thing. I
> >
> >won't go into
> >
> >>   detail on how I did this until later.
> >>
> >>   I've learned at work, that extreme brute force and extreme mass of
> >>   machinery is important to get the results necessary. Heavy metal
> >
> >is good!
> >
> >>   However, it's expensive. The machines that I work with cost a TON
> >
> >of money.
> >
> >>   We're talking 600 thousand dollars for a small one. My first 4k
> >
> >coco was
> >
> >>   $300 and took a couple of pay checks to pay for it. So, I won't
> >
> >expect to do
> >
> >>   what those monsters can do. I just want to make some small gears,
> >
> >sprockets
> >
> >>   and pulleys. Later, I want to do some 3D stufff, small things.
> >>
> >>   More later....
> >>
> >>   George
> 
> 
> 
> -- 
> Cheers, Gene
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Yahoo.com and AOL/TW attorneys please note, additions to the above
> message by Gene Heskett are:
> Copyright 2007 by Maurice Eugene Heskett, all rights reserved.
>