ml>> ummm... some years back, i was highered to install and set
 ml>> up a series of CAD/CAM workstations for an engraving
 ml>> company... i don't remember the language spoken between the
 ml>> CAD and the CAM but i believe it was DXF...

 RJT> That sounds familiar,  I believe it's the name of a file
 RJT> format.

i know the files are something.dxf... and i used to look thru them when i'd
export them from autocad... in a way, its almost like reading postscript...

 RJT>  There are also a couple of fairly standardized
 RJT> plotter "languages" and some of the software that's out
 RJT> there will no doubt provide those as output.  Or a plotter
 RJT> driver will.

yup... the thing is that it would be part of the DIY aspect, wouldn't it?
somehow, you'd have to code something that told the system that x=+1 might
be to move the x access in the positive 1 step... its been a while since i
dabbled in engineering areas... i forget, at times, about computers talking
to computers for some of this stuff... it could be as simple as that x=+1
causing a pulse on one pin of the parallel port and that pin being cabled
to the positive side of the x axis motor... i'm getting into some of this
type stuff with telescopes and computer controlled tracking and positioning
and such... seems to be very similar... two motors for guidance and there's
also some new stuff working for a third motor in the mix to eliminate
having to align the scope in the traditional ways...

 ml>> in any case, the CAM platform was fixed in place and you
 ml>> anchored the flat material to be engraved... the engraving
 ml>> stuff was basically little more than the (old style?)
 ml>> "moving cross" flatbed plotter movement with a dremel type
 ml>> tool attached to a z-axis for automatic height adjustment
 ml>> and precision control instead of the pen-up and pen-down
 ml>> type stuff...

 RJT> Y'know,  I have a dremel tool and the thought never occurred
 RJT> to me that it might be a thing to use for this.  

it might... though i've burnt up a few simply by using them for too long in
a session...

 RJT> Mine is an older model for which the common accessories are
 RJT> no longer available,  and i was lucky to be able to find
 RJT> collets for it,  all four of them.  But somebody pointed me
 RJT> to a source where I could buy a "drill press" setup for it
 RJT> that was made by a third party.  Perhaps something like that
 RJT> would be useful,  adaptable to this sort of thing.

cool...

 RJT> I hadn't envisoned much z-axis motion being necessary,  do
 RJT> you think I'd need much?  And precision in it at that?

sure... think about etching "relief" art (i think that's
right)... basically, you don't want to just drop the cutter head right into
the material... you'd want to ease it in to the proper depth... depending
on the material, you may need to make several passes with each being deeper
than the last... and what i was thinking about "relief" art was
along the lines of small sculptures or even being able to work with
material that's not flat...

 ml>> the stuff came with its own CAD package but these guys
 ml>> already had autocad and just stayed with it...

 RJT> Probably a lot more to it than the one that came with the
 RJT> machine.

autocad is/was the bee knees when it came to cad software... i don't know
what the current leading package is, these days... i got a copy of v2.1.1
some 15+ years ago and it was $3600+ at that time... even then, it did
wireframe 3d stuff...

 ml>> this is why i believe the the talk between the CAD and the
 ml>> CAM was dxf...

 RJT> Yeah.  You mentioned something about engraving?  Was that
 RJT> what they were doing with it?  My thinking was along the
 RJT> lines of circuit boards,  machining rather than etching,
 RJT> and perhaps the drilling,  and maybe some other things.

the ones that i was working with were doing plaques and trophys... name
plates and such... they could etch many materials but metal and wood were
the most common... though i did see them working on getting the movement
speed right for working with solid blocks of plastic some company wanted
something done with... AIR, something about "reverse etching"
such that everything was mirror imaged and what would normally be etched
out was left as raised material... basically like making a stamp or mold or
something... once they got the prototype samples done, they were looking at
processing orders of 10000 lots or more...

 ml>> i'd love to DIY one of these... if nothing else, it'd give
 ml>> me something easy enough to do and market and keep me
 ml>> busy... i've run out of ideas and the job market isn't
 ml>> giving me any hits, either ;-(

 RJT> You in the market too?  I got "terminated" last wednesday...
 RJT> :-(

kinda pretty much... been doing a lot of stuff just nothing steady ;-( 
getting tired of hunting down my paycheck from week to week... the economy
is so bad in this area that if you hear about any type of job opening,
you'd best be there waiting in line like folk do for concert tickets...

 RJT> I went to an agency today that I'd worked before,  and they
 RJT> cut me loose on a testing machine,  so I started picking out
 RJT> all this tech stuff just to see how I would do.  I found it
 RJT> bothersome how much windoze-centric stuff was in there,
 RJT> particularly questions about w2k,  and you couldn't skip

yeah ;-(

 RJT> them but had to guess,  but on some of them I did pretty
 RJT> well.  I may go back there and play with it again,  at some
 RJT> point.  They tell me that I can also access the system from
 RJT> elsewhere,  over the 'net.

i've got access to stuff like that here, too... and one of the real
stingers is that people don't think that i'm looking because i don't always
leave the house or make phone calls... there have been numerous loud
discussions about that and total refusal on their part to even come in and
look at the evidence ;-(

 RJT> But anyway,  this is a project that I've been thinking about
 RJT> for quite some time now.  Years at least.  I don't expect to
 RJT> make much progress in terms of actually doing anything with
 RJT> it while we're still stuck here in this little apartment,
 RJT> but that's no reason why we couldn't kick it around some,
 RJT> either here or in some other channel,  as appropriate.
 RJT> Maybe ELECTRONICS for designing some of the driver
 RJT> circuitry,  etc.

i hear that >

 RJT> Need some stepper motors?  I have a whole box full...  :-)

 RJT> Best ones,  for sheer size,  come out of old *big* printers
 RJT> (daisywheel,  etc.) and 5.25" floppy drives.  I saw a
 RJT> regular milling machine one time that had some the size of
 RJT> soup cans...   :-)

there are times that i've wished i'd kept much of the stuff i've tossed...
i've been slowly weeding thru things, cleaning out the place... couldn't
even walk thru the house without running into something or having to turn
sideways to get thru... i can see most of the ceiling, now... and several
boxes of stuff to take to the recycler's place... geez, i could have a
pretty decent handyman's yardsale if there were a real call for old
electronics parts and such... too bad its against the neighborhood charter
to have a yardsale and i'm not toting it all to the truck to move to some
place where i have to rent a booth and such... i do know that i've carried
over 1500 pounds of stuff out... the recycler has to weight the truck going
in and coming out...

)\/(ark