Re: [CAD_CAM_EDM_DRO] Re: Members

Smoke wrote:

> Where do you get the 3D paper for drawing the Z moves?
>
> Smoke
> ----- Original Message -----
> From: "Jon Elson" <elson@...>
> To: <CAD_CAM_EDM_DRO@yahoogroups.com>
> Sent: Monday, October 15, 2001 11:15 PM
> Subject: Re: [CAD_CAM_EDM_DRO] Re: Members
>
> > Art Fenerty wrote:
> >
> > > Jan:
> > >
> > > I never thought of that, a plotter WOULD be great for verifiing
> > > programs. I gotta start looking for a cheapo for that! They tend to be
> > > fairly cheap.
> >
> > I put a spring-loaded ballpoint pen cartridge into a 1/2" diameter piece
> > of shafting that I can mount in a collet. I use it to verify NC programs
> > right on the machine. And, it does draw a picture of the toolpath, too.

Pen plotters don't have 3D paper, either. For the few times I really need
it, I wouldn't bother having a separate pen plotter around, just for
that purpose. The machine tool itself can do the job, and it takes the
G-code explicitly the same way as when it is cutting metal.

I have done VERY little 3D work, there are just a few parts that have
actually had a shape to the bottom of a cavity, or whatever. For those,
I just have to trust Bobcad/CAM, which has never lied (ie. the G-code
was exactly comparable to the toolpath shown on the screen.) In
one case I couldn't get the toolpaths on the screen to do exactly what
I wanted, but the cut mirrored the screen exactly.

For some of the stuff I do WITHOUT CAD/CAM, ie. write my G-code
directly or use one of my g-code writing programs, I sometimes use
tool radius compensation, and that gets into some interesting details
having to do with inside corner radius and lead in/lead out paths. Testing
programs with the pen proves out what will get cut before i setup the
part.

Jon