Re: [RE: emc really needs a copyleft cad/cam package]

[Anne Ogborn <anniepoo-at-netmagic.net>]

First list of wants - all this predicated on the assumption that the CAD system is elsewhere.
t is , of course, just a list of wants. 

- I have to have 3D views of the final object. I mostly do contoured
work

- Ability to store a library of cutters. Rapid, well designed 
interface for saying "Do the rough cutting with THIS cutter in
THIS material, then the fine cutting with THIS cutter in THIS material".

- generates contour cutting of material with cuts deep enough to require
several passes.

- ability to designate pockets to be cut in specific order.
Suppose I'm making a bracket from plate. The bracket has a lightweighting
hole in it. I want that cut before the bracket is cut from the stock.

- ability to combine "tool path" oriented with "relief" oriented tooling.
For example, I'd like to make some little railroad car models for some friends as
Christmas presents, sort of a very short run kit. Most of it is just piercing a
sheet of styrene to cut out shapes. But a couple places there are fancy nameplates
and rivet strips that have to be relief engraved. I'd like to be able bring in a 3D
model, generate a cutting path for it, then bring in a path for piercing.

- auto convert between bitmap height data and relief contours.

- toolpath offset

- notch-in/notch out generation for flame cutters (there's something else needed,
I've forgotten what)

- autonesting.

- "Manual drive" - tools to help set up the jig/ set the zero point
For example, one irritating thing about the Roland's supplied software is that you can
only move the tool manually to the four corners of the workpiece, yet you have to use
buttons on the machine to set the zero - hard to do if you don't have a zero height
reference at 0,0!
basicly, a software "pendant"

- Move, scale & rotate

- import of cutting paths from elsewhere

- automagic cleanup of cutting paths

- flexible means of accomodating different machines

- 4th & 5th axis

- automagic doing of the "square corner with a cone" trick on 5 axis machines
(and more generally, handling of undercuts with such machines and hexapods)

- Ability to describe cutter shapes to the system - I don't want to be stuck because the
machine doesn't have the notion of a round cornered cutter. I'd like that to include the
ability to define what the cutter shank/spingle nose looks like so you can check for cutter
shank interference. For a lot of my work I've found this important.

- Automatic check for interference with the cutter shank.

- Rapid prototype machine path output.

- proper handling of side relief machining using cutters with diameters larger
than their shanks. (For example, suppose I want to make an odd shaped "plug", which
is to have a rubber O ring in the edge. I need to cut a groove for the O ring. I use
a cutter with teeth on the side.

- automatic surface treatment paths

- support for asking the operator to change tools for those without auto tool changers.

- Support for letting the operator zero in the tools for those of us without preset tool holders.
(For those puzzled by the above, consider my machine - I change tools by removing the spindle,
loosening a setscrew, slipping a new tool in, and replacing the spindle. Now I have to figure out
how to set the zero height for the new tool).

- excellent handling of interruptions in the cutting sequence. For example, if you break
a tool, you often can salvage the job if you can manage to "back up" a bit and restart.
This obviously requires some cooperation from the machine controller.

- support for various machine controllers. Seems a pity to build all this, then exclude non
EMC users.

- Support for "final" passes that use 2 or more different tools. 
For example, I do model railroad buildings with flat walls that have plaster decorations on them.
I'd like to finish off the walls with a flat ended cutter so as to get the best surface finish,
but I need to use a round nosed cutter on the decoration.

- Manual path editing, to get rid of that one little bit it generated that is messing everything up.

- ability to import a wide variety of 3d formats

- ability to import a 3d object as the stock. 
Imagine a production run - a manufacturer has 4700 pump bodies that need various faces machined
flat. With this feature she can import her 3d model of the pump body casting as stock, her model
of the finished pump body as part, and then generate
the needed cutting, without making a lot of wasted motion in the machine cutting off imaginary metal
and without a lot of need for fiddling about with manual path generation.
My current CAM software insists on neatly finishing off the edges of the block of stock. I wish I
could convince it not to do that. This would make a nice solution.

- ability to import 3d objects and mark them as "clamps" - areas into which the tool must not
traverse.

- ability to graphically edit the generated path - for example, I make a lot of one faced molds
relieved into wax. my machine often insists on finishing
the front face of the stock. I don't need it to do that, and it's very time consuming. I'd love
to be able to delete all this cruft.

- machining time estimates.

- animated machining simulation, with "player" type controls so you can scroll forward to the interesting part without watching
the whole thing.

- automatic abstract generation
   An abstract is the flat area machined around a "bump" cut from stock.

- ability to specify tool path generation - x, y , contour
My Modela software only lets you do contour for the rough cut for some reason, which is silly

- climb/down milling selection

- selection of margin width.

- command to have the machine surface the stock. Perhaps combine with the "stock import" command
above so this could be on a complex piece of stock. Be nice to designate which parts of which
faces need surfaced.