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Existential Angst Existential Angst is offline
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Default How much can you do with 1000 lines of G-code?

"_" wrote in message
. ..
Some demo versions of CNC software have a line limit - how limiting is it?


The quick answer to your Q: shouldn't be a problem at all, as a demo, and
even as the full pgm!!

And yeah, as Pete said, g-code pgms put in all kinds of **** I don't
understand.
I have never used a program, just Wordpad or any wordprocessor that will
save files as text. There are really not that many codes you use for run of
the, uh, mill parts.

In my whole miserable prototyping career, and running a number of jobs for a
miserable job shop, I don't think I've ever hit the 1,000 line mark -- even
with a 4th axis.
For repeat offsets (like for a 300 pocket job coming up), it behooves you to
use macros, which basically are just loop counters in their simplest and
perhaps most common form, and the simple-ish moves go in sub-routines at the
front of the program. The macro calls and executes the subroutines 300
times.
So those 300 pockets per plate will fit in maybe 50-80 line program, for 5
tools.

For typical spot/drill/tap/pocket/post/circ interpolation, each tool is
mebbe 8-12 lines of code, mebbe less.
For the spot/drill/tap sequence, I'll put all the coordinates in a small
sub, and call that sub for each of those tools -- that way, you can't have
inconsistency errors, like tapping at a coordinate where a hole was not
drilled.
This is a win-win technique, where you gain simplicity, reliability, and
save lines.

A typical "real part" program is about 200-400 lines long, and that's
without me being particularly economical code-wise. Over 400 lines, I start
moaning/groaning/whining/complaining..... That's mostly 2.5 axis, but even
with full 3-axis moves (kind of a rarity over here) or with the 4th axis,
the prgms don't seem to get much longer.

The Fadal controllers allow you to call sub-programs as well. So a 100-line
program could call a 300 line pgm, a 500 line pgm, and an 800 line pgm, one
right after the other. I have never done this, but the machine allows it.

My Fadal 3016 L has some ridiculous bitty memory as well, either 32 or
48K -- that's right, K -- which can handle, iirc, mebbe 4,000 lines at once.
I seem to remember my near-1,000 line pgm gobbling up about 25% of its
memory.... goodgawd, the KayPro had effing 64K, iirc.....

Also, it will depend on what "canned cycles" (pre-programmed) cycles are in
the program/machine. If you have to program in your own pecking, bolt
holes, etc, that will lengthen the program.

Post this in alt.machines.cnc as well. I'm sure those guys have exceeded
the 1,000 line limit, but I haven't.
No NASA-type work over here, tho.

--
EA