Smithy Ez-Trol2 - Manual (Page 55)

UNDERSTANDING G-CODES
OVERVIEW
This chapter is designed for the less experienced G-code programmer is written to give the novice
a bit more assistance in learning about G-code, why it’s important and how to do it.
WHY WRITE YOUR OWN G-CODE?
While most machinists today are using CAD/CAM systems for designing parts to be machined on a
CNC machine, it is still essential for the designer/machinist to have an understanding of G-code.
When converting a CAD file to G-code using a CAM program, most often there are errors in the CAD
design data set that need to be corrected in order for the CAM program to finish verifying the design
and processing the necessary G-code. These errors come to light when the request to Create Code
is made in EZ-Trol and the operator is informed that there are errors in the resulting G-code. These
errors are generally the result of miscalculations in the CAD design. Someone is going to have to
know enough G-code to analyze the discrepancies between the design and the CAM interpretation,
determine what the original intent of the design was and then make the necessary corrections to
the G-code. A programmer’s reference manual is provided with your EZ-Trol manual. It is an
excellent tutorial on G-code programming.
Often, machinists who are familiar with G-code find it quicker to manually write a G-code program
for a simple part design. This can be done standing at the control and doesn’t require the operator
to leave the machine to go “sit at the drawing board”.
There are a number of good books that can help you learn more about G-code programming, in
addition the “SmithyCNC G-code Programmer’s Guide”. The internet is also a good source of
information. Generally the best way to learn is to just get in and practice.
NOTE: Many of you may not have the desire or the time to learn G-code programming well, but
you still have the need to make parts on your SmithyCNC machine. One of the big differences
between Smithy and other benchtop CNC providers is that Smithy has a low cost service that will
assist you in designing your part and converting it to G-code in preparation for machining the part
on your SmithyCNC machine. Generally, for as little as $20/hour, an experienced CNC machinist/
programmer from Smithy company can fix up your CAD file and convert it to a G-code file that can
be used in your machine. This allows you to get work done with little hassle and at low cost. It may
be just the ticket to make your CNC machining operation run most efficiently. Why go through the
effort to learn G-code programming if you aren’t going to be programming every day? Use your
time wisely and use a professional programmer from Smithy.
The rest of this chapter will go over, block by block, a sample program of the G-code for machining
the fan adapter. Hopefully having this step-by-step breakdown, with accompanying commentary,
will help you get more into the mindset of G-code programming.
13
www.smithycnc.com | 49