Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: trunkhaus on July 02, 2008, 10:56:56 AM

Title: classes on g code and mach 3
Post by: trunkhaus on July 02, 2008, 10:56:56 AM
does anyone know if there are classes you can take to learn g code and the mach 3 software, i am a hands on type of learner so i would prefer an actual class format with workshops to computor classes. i live in S.E. Michigan so if there are no classes, i would be willing to pay an individual to teach me one on one.
my email is trunkhaus@yahoo.com please let me know as i am recieving my machine on or about Aug. 15th and would like to know how to some what run it and be able to program my patterns into it when it arrives.
purchased a Vortech s408 4 x 8 cnc router with vaccuum holddown.
any help would be greatly appreciated.
thank you in advance.
Trunkhaus
Title: Re: classes on g code and mach 3
Post by: RICH on July 02, 2008, 06:14:10 PM
Hi trunkhaus,
Here is a link to a "free" program which you may find usefull in learning G code.
I am sure there are others.

http://www.betatechnical.com/autonc.htm

RICH
Title: Re: classes on g code and mach 3
Post by: Chaoticone on July 02, 2008, 06:43:06 PM
Thanks for the link Rich! Looks pretty neat.

Brett
Title: Re: classes on g code and mach 3
Post by: ger21 on July 02, 2008, 08:21:50 PM
does anyone know if there are classes you can take to learn g code and the mach 3 software, i am a hands on type of learner so i would prefer an actual class format with workshops to computor classes. i live in S.E. Michigan so if there are no classes, i would be willing to pay an individual to teach me one on one.
my email is trunkhaus@yahoo.com please let me know as i am recieving my machine on or about Aug. 15th and would like to know how to some what run it and be able to program my patterns into it when it arrives.
purchased a Vortech s408 4 x 8 cnc router with vaccuum holddown.
any help would be greatly appreciated.
thank you in advance.
Trunkhaus

What CAD/CAM software do you plan on using? And do you have a link to the Vortech machines? I couldn't find any info on the web.

I'm in Shelby Township, btw. Are you near here?
Title: Re: classes on g code and mach 3
Post by: Overloaded on July 02, 2008, 08:24:12 PM
http://www.vortechcnc.com/artisan-408.html
Title: Re: classes on g code and mach 3
Post by: vmax549 on July 02, 2008, 08:44:13 PM
HUM I didn't know Mach3 could do hpgl or PLT code???????

(;-) TP
Title: Re: classes on g code and mach 3
Post by: RICH on July 03, 2008, 09:11:39 AM
trunkhaus,
Here's a link to a "free" course to get get you started:

http://technology.calumet.purdue.edu/met/mfet/275/coursematerial.htm

Here's a simple easy "free" program which you can just type commands and see movements :

http://www.ncplot.com/ncplotfree/ncplotfree.htm

Then maybe you can use the other posted program for more advanced stuff.
Hopefully this gives you a progressive path to follow.












Title: Re: classes on g code and mach 3
Post by: trunkhaus on July 03, 2008, 10:16:25 AM
wow, thanks for all the reply's and info, you guys are great. ;D
ger21 i am in hartland on us23 and clyde rd.
i am totaly new to this cnc stuff and decided to buy a machine so i could transfer all my patterns for my company into cutting files, so i would no longer have to cut them by hand, and was hoping to sub let the machine out to others or possibly get a parts line to keep it busy when i am not using it. it appeared to be the best machine for the price, as i recieved a free vacumm hold down system with it, and the other machines i looked at with the same features but with a lesser table design where in the $20,000+ range and this one was $14,000 delivered, with 2 days of free schooling on the machine so i went for it.
hope it was a good deal in the long run.

thanks again guys
Trunkhaus
Title: Re: classes on g code and mach 3
Post by: jimpinder on July 03, 2008, 01:25:57 PM
There is no better way to learn GCode (and Mach 3) than by sitting down and doing it.

Basic GCode is very simple. The X and Y axis have co-ordinates, and a line of code tells your machine to move from where it is (it knows where it is) to a new location. That is it.

If you mention one axis in the line, than one axos moves, if your mention two axis, then both move simultaneously in time with each other, and if you mention 3 axis at one time you are better than me - but the same rule applies - all axis move simultaneously.

The move can be at hgh speed - i.e. what your motors are set at for top speed by using G0, or you can use G1 where you can specify the speed the axis(es) travel at - using F (Feed) in units per minute.

The codes G2 and G3 are for cutting an arc. This is a circular arc, as opposed to a hyperbola or other type. Here, as before the finish points are required, together with a radius (R parameter) or a centre paramter (I or J or K).

These codes are all that is required to make your machine do meaningful work. The other codes listed are all to do with offsets, or specialist drilling moves, or metric and imperial, etc, to make the first four codes do the job at the correct place - and, quite frankly are ignored by a lot of the Cam programs, which simply write what they want to do in the first 2 codes, G0 and G1.

Get stuck in and sit down and write some GCode program for yourself. Get some graph paper, which gives you a co-ordinate system, and draw out on that, where you want your tool to go, and then write the GCode to match it. You will be amazed that you can achieve so much with so little.

As you progress, you will investigate if there is a more efficient way of writing the Code, and there might be, but as I said before, many of the CAM programs are not efficient, they stick to writing things in lots of little lines.

The most important thing about all this is to make sure that you write your program, from a point 0.0.0. This is a point that you can set on your machine and know that when you start your program, the machine knows where it is.

One a lathe, X0 is normally the centreline of the lathe bed at rotation height, and Z0 is normally the right hand edge of the workpeice, both things you can easily find.
On a mill, X0Y0 is normally the bottom left hand corner of the workpeice, with Z0 being with the tool resting on the top of the workpiece, again a place that you can easily find - and more important in both cases - you can set your machine to.

These places are known as Work Co-ordinates. The machine itself always runs in Machine Co-ordinates - and the Mach DRO's display either. As you get more proficient, you will learn (or should I say - come to understand) how you can have the machine set itself to home co-ordinates, then apply offsets to bring it to the correct place to begin work. That, however, is a fair way in the future, and something you do not need to know at the present time.

Keep it simple at first, have a go writing your GCode and you will learn very quickly.





Title: Re: classes on g code and mach 3
Post by: trunkhaus on July 03, 2008, 02:13:07 PM
thank you for the advice, is there a handbook on g code you would recomend, so i can keep it by the machine incase there are any questions i do not have to run up to the house to log on to the net.
maybe something like a beginning nc code book or g code for dummies?
Title: Re: classes on g code and mach 3
Post by: jimpinder on July 03, 2008, 02:41:50 PM
you could try this .

Even this, to me, is a bit fussy at first, but does contain some decent explanation of the syntax of GCode in the later paragrahs.

Print it out and stand it by the computer.

There are Books on the market, but I wouldn't know which to recommend.

www.linuxcnc.org/handbook/gcode/g-code.html (ftp://www.linuxcnc.org/handbook/gcode/g-code.html)
Title: Re: classes on g code and mach 3
Post by: budman68 on July 03, 2008, 02:48:22 PM
I believe Jim meant this website:

http://www.linuxcnc.org/handbook/gcode/g-code.html
Title: Re: classes on g code and mach 3
Post by: Hood on July 03, 2008, 06:23:20 PM
The G-Code button on the Mach screen opens up an html doc which gives a brief desription of each G Code, that might help you.

Hood
Title: Re: classes on g code and mach 3
Post by: Ron Ginger on July 04, 2008, 03:01:01 PM
Dont waste your time studying G code. You will only write the most trivial of programs by hand. For any interesting work you will need to use some software to generate the code. Pick a good CAM system and lean it.  Any interesting parts will be thousands of line long, no one can write that directly.

For plain mechanical work I use Sheetcam. I recently bought Vetric Vcarve Pro and think its great for the more artistic and sign making work.
Title: Re: classes on g code and mach 3
Post by: ger21 on July 04, 2008, 10:38:00 PM
Dont waste your time studying G code. You will only write the most trivial of programs by hand.

Knowing what the machine should be doing (by understanding g-code) when it's not can sure make troubleshooting easier, especially for a beginner. I see a lot of people that have no idea what's causing there problems, when a quick look at the g-code can tell them instantly, if they knew what they were looking at.
Title: Re: classes on g code and mach 3
Post by: jimpinder on July 05, 2008, 02:56:41 AM
Yes - I didn't mean for you to try and become a GCode expert - but as Gerry says - knowing the GCode helps to troubleshoot.

Ron - I think your approach might not be universal - I have a friend who has some BIG CNC machines - your have to winch the workpiece into place. He is maching parts for oil pipelines out of solids - and he writes all his own code. I am an engineer and the parts I make tend to be simple, axles and things and I write my code, because Solidworks takes too long.

Those who have written to the forum recently about jerky movement in CV and Adsolute Stop need at least to be able to look at the code and have a reasonable undertsanding of it, to be able to determine if their CAM system is writing arcs or lots of straight lines.

I want to do some nameplates next (not engraving) where the letters stick up from the backgorund - now I might need a CAM program for that !!!
Title: Re: classes on g code and mach 3
Post by: Ron Ginger on July 05, 2008, 08:44:37 AM
I agree that we need to be able to read basic Gcode. But I do not think one needs to spend days learning what is really trigonometry to be able to write G code. Even the simplest projects are likely to be more accurately done using decent software to generate the  code.

I have made several signs and name plates and obviously they would be impossible without CAM software. For simple tasks, like facing stock or circular pockets or bolt circles then use wizards to generate the code.
Title: Re: classes on g code and mach 3
Post by: jimpinder on July 05, 2008, 09:27:02 AM
I must agree that most of my code is now a step up from writing lines of code longhand, because most of my regularly used programs are GCode macros in Vis Basic. I fill in various parameters and the Vis Basic generates the GCode directly to the machine, I never even see it.

All in all then, get to know your way round GCode, but don't spend too much time on it, there is lot's more fun to be had with good CAD and CAM programs.
Title: Re: classes on g code and mach 3
Post by: RICH on July 06, 2008, 10:35:01 AM
Hi All,
Will use myself as an example.
I need enough to know how to use the MDI line to move the tables around and setup the job. Use the wizards because they just make things so easy and provides a nice place between writing code on one end and using CAD / CAM on the other end of the spectrum. The niche spot wizards provide, is you can use the CNC machine to do typical tasks and not feel it's easier or quicker to do it manually. On the CAD / CAM side you just can't beat having the code generated for complex things by a program. I could never write the code for the engraving work I have done. All the programs give you some quirky code and the ability to scroll down  / simulate the code , remove that one stupid line or lines, and know the effect is almost "mandatory".

I tend to learn what is needed to enjoy my bobby and constantly enhance as required. Remembering when I knew nothing about Gcode, just read the different definitions, played with the moves in a few programs and on paper until pacified. Got bored with that and went into using a CNC program to make chips.

When I reflect on CNC, it's not only the Gcode. CNC is quite complex, to a beginner overwhelming, computer, CAD, CAM code, controllers, wiring, machining experience, engineering expertise, etc.. Just think if your main background is only basket weaving it sure could be a challenge.
Gcode is only one part of the of the big picture. If it's your thing go for it!
RICH