--- In mach1mach2cnc@..., "Jeremy Taylor" <jt@j...> wrote:
I have no control over CW, OR CCW rotation, all I can set is speed,
and at
30000rpm my experience has shown that cuts just as well in either
direction,
If I was using the tool by hand, it would feed easier in one
direction, but
now that it's cnc'c - it's just as smooth in either direction.
Consider the cutout a square, as you follow the line on the inside,
the
compensation would have to change, from being off to the left,
under, off to
the right, and above ~ the line. If the tool path was like I'd do
it by
hand (in once, out once), but instead the tool comes up and re
enters a
couple of times
Trying to keep track of which section of a single cutout need G41,
or G42
is driving me crazy.
As soon as I recover from purchasing a plating system, I will
invest in
decent cad/cam package, although All I need is "simple!" 2d cutouts.
For giggles here is an example of what Mach2 came up with from my
dxf
import, attached is gif of what it supposed to look like. It's for
a snap
in AC outlet. (everything inside the lines need to go, but nothing
on, or
outside the line should be cut.
(in MM)
F20.000000
G0 X0.000000 Y0.000000 Z0.200000
M3
S20.000000
G0 X0.000000 Y0.000000 Z0.200000
G0 X0.050800 Y18.262600 Z0.200000
G1 X0.050800 Y18.262600 Z-0.100000
G1 X8.483600 Y18.262600 Z-0.100000
G1 X8.483600 Y24.257000 Z-0.100000
G0 X8.483600 Y24.257000 Z0.200000
G0 X17.780000 Y24.257000 Z0.200000
G1 X17.780000 Y24.257000 Z-0.100000
G1 X17.780000 Y18.262600 Z-0.100000
G1 X26.187400 Y18.262600 Z-0.100000
G1 X26.187400 Y7.950200 Z-0.100000
G1 X22.199600 Y7.950200 Z-0.100000
G1 X22.199600 Y0.000000 Z-0.100000
G1 X3.987800 Y0.000000 Z-0.100000
G1 X3.987800 Y7.950200 Z-0.100000
G1 X0.000000 Y7.924800 Z-0.100000
G1 X0.050800 Y18.237200 Z-0.100000
G0 X0.050800 Y18.237200 Z0.200000
G0 X8.483600 Y24.257000 Z0.200000
G1 X8.483600 Y24.257000 Z-0.100000
G1 X17.780000 Y24.257000 Z-0.100000
G0 X17.780000 Y24.257000 Z0.200000
M5
G0 X0.000000 Y0.200000 Z0.000000
I'm assuming I'd need a g41 or g42 before each point where the Z re-
enters
the work. I believe this import DXF was already hand drawn smaller
by 1.5MM
JT
There comes a time in most CNC'rs lives when they realize that CAM is
a good thing. Just like a calculator makes math easier than with a
pencil, when the important thing becomes the part and not the action
of laying it out, CAM takes all of the durgery out and does all of
the calculations for you. In a good CAM program you should see the
orginal part on the screen. You should be able to click on a path
and and choices for a tool, depth and speed are one click away. The
choice of tool should automatically put the toolpath where it should
be after you select an on-line, inside or outside cut. More advanced
programs also let you decide which direction you cut. It's last job
is to spit out a valid g-code file that will run without a problem on
your software controller.
For those that complain that they want to change the toolpath in g-
code at the machine, they guess they feel the need for control. It
takes less than a minute for me to go back in my CAM program (one
reason I like running a Windows controller like MACH2) and change the
tool definition and recalculate the toolpaths. I guess I have gotten
lazy over the years and I require a less hands-on approach to cutting
things. I remember when we had to hand code everything from a
blueprint into g-code and punch it in a papertape. Any changes took
hours. I LOVE the fact I can draw something, click a few buttons and
have the machine running the part in a few minutes. I don't miss the
hand coding one bit.
TC
