View Full Version : New CNC Mill, Advice on Training

02-10-2010, 11:46 PM
I have just received my first CNC machine, a Jet knee mill with the Accu Rite Mill Pwr 3 axis CNC system. I have no experience with programming a CNC machine, G codes, CAD, or MasterCam. I was going to sign up for a class at my community college but I am not sure what order I should take them or which ones would give me the most bang for my buck. They have a class on Solid Works, a class on Master Cam, a class that is an introduction to CNC that seems based around learning the G codes and programming. Another class that is an introduction to CAD/CAM that seems based around writing a mill program on a PC. Below are the official descriptions. Each class is a significant amount of time and resources for me so any advice I can get would help me a great deal.

PMT0251 Introduction to CNC Machining (PSAV)

Course Description
The basic set up, operation and programming of Computer Numerical Controlled (CNC) machines are covered. Student will coordinate activities of the CAD/CAM software packages and the machine controls to produce hardware to blueprint tolerances.

PMT0258 CNC Milling Methods (PSAV)

Course Description
This course will develop advanced level competencies in the operation of Computer Numerical Controlled (CNC) milling machines and create CNC code from parts geometry. Students will demonstrate safe operating procedures and standard set-up and control of CNC milling equipment.

PMT0260 Introduction to CAD/CAM Programming (PSAV)

Course Description
This course provides an introduction computer aided operations for machining technology. The students will familiarize with the basic operation and programming of Computer Numerical Controlled (CNC) machines and Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM). Students will use CAD drawing and CAM programming techniques to design, program and machine a part using the CAD/CAM process.

TIO0350 SolidWorks Software Introduction

Course Description
SolidWorks CAD software for mechanical 3D modeling offers fully integrated, easy-to-use analysis tools that allow you to test multiple "what if" scenarios and optimize your designs from within SolidWorks. Learn the fundamentals of computer based modeling to design and assemble parts before they are created in the machine shop. Topics include a general introduction to the user interface, menus, toolbars and broad concepts and modeling techniques to create parts, assemblies and drawings. The designer can visualize their part on the computer screen before it is prototyped in the machine shop. This class is instructor led with hands-on learning.

TIO0353 Mastercam Programming Intro

Course Description
Prerequisite: Computer drafting and some exposure to CNC machining. Mastercam is the most commonly use CAM software worldwide and remains the program of choice among CNC programmers. CAM programming software delivers the most comprehensive milling package with a simplified, customizable interface, more power, and even faster, robust tool path calculations. The Programmer can visualize their part program on the computer screen before it is actually cut on a CNC machine in the machine shop. This class is instructor led with hands-on learning.

TIO0360 CNC Programming Intro

Course Description
Discover the fundamentals of programming a Computer Numeric Control (CNC) machine used in many machine shops today. A CNC milling machine allows the student to create parts, contours, pockets and shapes that would be extremely time consuming if not impossible on a manual knee type mill. Upon completion of this course, the student should be able to create a G-code program from scratch using all the involved principles.

Jim Shaper
02-11-2010, 02:02 AM
"TIO0360 CNC Programming Intro"

Learn to crawl before you run (your spindle straight into your bed). ;)

Seriously, you want to know how to talk dirty to your control in it's native language (word address format) before you worry about how to get funky with CAD/CAM.

The guys I see doing the classes out of order are majorly confused and not really learning what they're supposed to when they get their hands dirty with the machines. Anyone can be taught how to push the green button and set a work offset - knowing how to make the thing follow an arc and what direction which letters are going to make the tool go is far more important than being able to power the thing on and run someone else's program.

In the mean time, you can play with the conversational control and see what kinds of parts you can make with it.

02-11-2010, 08:42 AM
You need to understand the g-codes before moving on to cad/cam. So take the basic class first.

02-11-2010, 09:46 AM
Intro to CNC machining would get you operational the soonest. Then learn G code programming to get the finer points and time saving shortcuts, then Cad/Cam.

02-11-2010, 09:55 AM
Xtreem, if you post a general area for where you live you might find someone here who could help you personally.

As far as the courses go, knowing G code isn't really going to help you with that control unless you plan on going to a cad cam program later on. That control if I remember correctly is strictly conversational and no where on the control are you going to see a G code.

You need to understand the basic coordinate systems to get started. Have you got any blueprint reading skills? That is the first thing I would try to learn because you will be lost in any of the other classes if you don't understand that. I tried to train a guy once who couldn't do basic trig and algebra and he had a heck of a time trying to progam the cnc because sometimes you have to calculate a point for the machine to cut to that is not on the print. If your an experienced machinist then that part you will understand so disregard what I said above.

It's hard to answer a question like this also with out knowing what you plan to make. If you are going all out into 3 axis machining then you will definitely need to get into cad cam at some point. But if you are doing basic 2 axis parts you might find that you can program anything you want at the control and have no need to learn cad cam. No need to muddy the water any more than you have to while getting started.

02-11-2010, 04:00 PM
I have the mill in my garage. I just replaced a Smithy 3 in 1 machine. I don't plan on machining anything too complex. Just a hobby. I make some motorcycle parts and a few trick pieces for my 4x4 truck, mainly just playing around because I see parts I like but the quality is poor so I make my own version. I realize it is going to be a long step by step proces before I come close to being able to use the full capabilities of this machine but I get tired of out growing tools and having to replace them every several years for the "next one up". I figure I woun't be able to out grow this Jet and Acu Rite system for quite some time.

02-11-2010, 04:17 PM
If you've been doing most of your work with a 3 n 1 then you will be pleasantly surprised when you get up and running with the new mill. Sounds like you could do perfectly fine programming at the control. By going this route instead of using cad cam you'll have quite a bit less things to try to learn.

03-02-2010, 08:25 PM

03-02-2010, 09:08 PM
You need to understand the g-codes before moving on to cad/cam. So take the basic class first.

No you dont. And we proved that at techshop. We had people cutting parts on a cnc mill in hours without learning any g-code. Set you cam for your control and have at it. Always do air cuts and keep your hand over the e-stop. If your machine has rapid override use it. I have never had cam put out code that disagreed with what is showed what was going to happen on the screen.

You dont know postscript, do you? But you can print to a laser printer just fine.

G-code is good to know, but it is not necessary to know before making parts.

Skip the solidworks and mastercam classes unless you plan on buying $15k of software or are looking for a job doing this professionally.

Uncle O
03-03-2010, 06:13 PM
Mill-power is chock full of canned cycles. just pick what you want to do and enter the info it asks for. Bolt circles...it will ask for X-Y center dim's, radius of the circle, how many holes and what is the start angle....3:00 being 0 deg.

Slots will ask for first arc center co-ords and 2nd arc center co-ords, and the width, or you can skip the 2nd arc center and just give it the length.

I just started using one 3 weeks ago at a new job, but it is a 2 axis, not 3....
can you dis-engage the Z axis and run that manually ? Used to run an EZ-Trak that was 3 axis , or you could run it as a 2 axis....