Re: [CAD_CAM_EDM_DRO] Re: Routine Chat Times

On Wed, 04 Jul 2001 10:14:21 -0400, "IMService" <imserv@...>
wrote:

>I am particularly interested in ANY comparisons of Bobcad and Vector.

I just posted most of this on alt.machines.cnc. but there may be some
here that don't subscribe to that list - so i will repeat it here.

I've got things working reasonably well now using BobCAD and
comeditcnc. Since I have spent money on them, I tend to focus on
learning to use them. I finally got the Anilam canned cycles figured
out and entered into the BobCAD MACRO menus, and the variable
definition lines in the comeditcnc glossary menu. I like the variable
feature of comeditcnc.

BobCAD seems to let me generate a path just the way I want it as long
as I am willing to wrap its basic tool path with a bunch of hand
programming. I frequently use BobCAD to generate the basic path and
do everything else in the editor.

I seem to have developed an approach, possibly out of ignorance, where
I put the basic tool path in a subroutine, then just call it when I
need it - using tool compensation commands to adjust for finish
passes, etc. When it doesn't work, its my fault, not the SW's fault.
I'm finding out that for my simple stuff, the tool path, the part
BobCAD does for me, is only about a dozen lines of code - the rest of
the 150 lines (typical) is inserting canned cycles for drilling,
entering tool definitions, adding comment lines about what this
program does, how to set up the machine, what tools to use, my
standard startup lines to make sure the machine controller is in the
defined condition my program expects (units of inches, absolute
measure, ...), etc. With out the comments, coming back to the code
months later, it will be greek to me.

I've wrestled with the Vector demo a little - time is precious. I
"want" to like that SW. First time I clicked on the icon and
VectorCAM generated about 30 lines of code, instantaneously, my heart
skipped a beat - whoo hoo, hot dog! Magic! I was so excited I could
hardly sit down. More, give me more! Then ... I read the code - it
was not good code. It was machining all over the part in a really
strange order. Doubtless an operator error here - something to do
with vectors. I'm doubtless telling it things I don't intend to -
like a novice rider on a well trained horse - the rider is continually
bewing surprised by what the horse does! I think I need to understand
better the constraints of the SW, selection order, etc.

The SW has reasons to like it. Mark W. recommended it to me. I get
the feeling if I could get my mind around its paradigm I'd like it.
Fred is here, BobCAD is off ... someplace (although one could make the
comment that BobCAD is about as intuitive a program as there is - for
me at least - there is no manual, the help files suck, I had to down
load the tutorial off their WEB page as html files, and yet I am able
to figure out how to use it - it may not work at all for someone
else). But, so far, with admittedly limited time available (on a good
week I get 4 or 5 hours to play in the shop or with the CNC machine -
and I've already given up watching "any" TV so no help there - can one
get more time by giving it up twice?), getting Vector to generate a
tool path "my way" isn't working.

For example: My machine doesn't have a tool changer. I like to start
by having the tool move to an out of the way place so I can change
parts, or tools, with out slicing my knuckles on cutters, etc., and
then pause. Pause on my machine, G29, is indefinite - a feature - it
would be really tragic to have it time out and begin running half way
through a tool change - having to hit the green button to continue
after G29 is good. I go back there and G29 to change tools, or back
there and end the program to put in new stock to rerun the program. I
like to have Z0.0 be at a location where the longest tool clears
everything if my limited Z travel will allow it. I like my first move
of the program to always, every single time, take Z to Z0.0 so the
first translation, even to zero, won't collide with anything. (The
result of a kinesthetic learning experience!) I have not been able to
communicate these to VectorCAM. The first Z move has the red pointer
moving off to some strange place on the part where I don't want to be.
Haven't been able to figure out what I'm doing wrong ... yet. I may
run out of time. Probably I need to RTFM.

In BobCAD I just use the "go to a point" icon, click, and its there.
then of course I have to add the G29 line by hand later. Same with
going to where I want to lower the cutter and begin cutting. Use the
go to a point icon, click where I want to end up, the pointer goes
right there, right now, no hassle. Then, of course, I enter the next
lines by hand - the "G00 Z-[initial-depth], G01 Z-[first-cut-depth] F
3" etc. commands and any other "Z" feed commands, the call the tool
path subroutine. Tedious, but it works.

Back to Vector: I haven't tried it yet, but maybe I just have to
select that "point" first, then the rest of the path, and then the
basic path commands will be what I want? Hmmm ...

I was able to draw some parts in VectorCAD just fine - no problem -
and have that disk here - it arrived n the mail the other day -
possibly the best deal since the Louisiana Purchase.

It may be that my detail oriented do it my self my way personality
isn't a good match for a highly (or even moderately) automated CAM
package. At least not yet. I might adapt better when I get tired of
all the typing? <G>

The side benefit to how I am doing it now is that I am learning to
read "G" code really fast. There is nothing quite like writing a lot
of it to learn it.

Perhaps that is the pony of the day?

Fitch
In So. Cal.

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