Instructions

codes can be read throughout the world. g-code standards came about very early in the
game because this game was controlled by engineers rather that marketing people.
Contouring programs—another world
Programs that allow you to do contouring quickly become very complex. Today there are
some affordable programs available for sophisticated hobbyists. These programs can
create as many problems as they solve, because of the complexity of each program. Each
program has to work with other programs, and each program has its own set of complex
rules. If you think you can learn these programs easier than you can solve a couple of trig
problems you’re in store for a rude awakening; however, if you already know how to use
3D CAD programs you could quickly find these programs very useful. It should also be
stated that it is the only way available to create contoured machined shapes.
What it costs in the industrial world
The basic method that these programs work together in the industrial world and the cost
of these programs is: 1) The part is designed using a modeling program ($5000 to
$10,000), 2) The modeling program is converted to a CNC program (another $5000 to
$6,000) and 3) the resulting code is run on a CNC machine starting at ($25,000) that
makes the part. The people who can operate these systems are carefully chosen, trained
and well paid. The fact is that any business has no choice except to use the program they
purchased, because the programs cost so much and are so very necessary to remain
competitive in today’s world. They have to spend a great deal of money to accomplish
this, while the hobbyist has a choice.
Today’s low-cost programs were once complex, expensive programs
The business world understands how complex it is to implement these procedures; the
hobbyist doesn’t. Because the hobbyist may be purchasing a program that cost thousands
of dollars just a few short years ago for a few hundred dollars, the programs themselves
haven’t become less complicated. They only cost less! In your mind you may be having
visions of complex shapes being machined with little effort on your part while your two
thousand-dollar investment turns out parts that the old masters of the machine trades
would envy. Well my friend it’s possible, but it’s time to come down to earth and again
think about the complexities of doing so.
Cutter compensation—what makes CNC work in a machining environment
I could have sneaked out the back door and only wrote instructions for a couple of simple
moves without cutter compensation and let it go at that; but deep down inside, I’d have
known I was cheating you out of the real benefits of CNC. I believed that if I started
teaching you to use this marvelous programming tool right at the very start it will soon be
second nature, and our class will leap-frog ahead of our competition with those thick
boring books being taught by instructors I wouldn’t let near the least expensive CNC
machine in my shop.
If you take the effort to learn this method of programming at the start along with a little
simple trig, you’ll find it well worth the effort. Cutter offsets are the way you control size
with modern CNC machines. When you start making more complex parts and you don’t
use cutter comp you’ll have to change the basic numbers of your programs to make a part
on size. Sounds simple enough until you find that every time you correct a number here
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