View Full Version : Lamentations of a newbie...


saturnnights
02-11-2006, 06:19 PM
Am I alone with the following issues?
When I assert that I'm a newbie, you have to understand that metalworking is totally new for me - been a woodworker all my life but bought a couple of mills and lathe over the past several months. The problem is with software and trying to teach myself to use my CNC Taig mill. Demos are restrictive enough to hamper my learning process with their 30 day expirations and limited features and inability to save to the formats that I need to test. I wound up buying Mach 3 to eliminate the 1000 line limit - probably the only purchase I won't regret. I also bought Rhino because of the 25 save limit staring me in the face and because I had to pick something that would save to enough formats to be able to test the different CAM apps that I'm demoing.
Sheetcam only allows 150 lines... Other CAM apps are about to expire and my full version of Rhino won't be here until Monday. I feel like I'm trying to teach myself something that just isn't very easy to pick up at home. I don't know of any other way for the software manufacturers to do it though - they have to put limits on their demos, but when you're in my situation, that pretty much screws you...

Anybody else find that they're trying to teach themselves CAD/CAM against the clock... And failing?

Mark

kdoney
02-11-2006, 06:45 PM
I did the same thing 4 years ago and hated having to make a decision based on more guess than fact; but I bought Mach and Rhino also and I haven't found anything yet I can't do. Taking one class at a community college doesn't hurt either. With the tuition, you can now buy at a student discount. Sometimes this is less than 20% of the retail price. Very few limit the functions on student copies. Oh, and the education hasn't hurt me none neither anyhow.

ger21
02-11-2006, 07:05 PM
One thing I notice is that a lot of people ask very general questions that are nearly impossible to answer, like "What software should I buy?". But once they buy it, they rarely ask questions on how use it.

There are plenty of Rhino users here, and plenty of SheetCAM users as well. Ask very specific questions, in the appropriate forums, and you should get all the help you need. As for Rhino, there are tons of tutorials on the web. Nothing will help you faster than working through tutorials, imo.


If you plan on using SheetCAM, I doubt you'd hit Mach 3's 1000 line limit unless you're doing pretty complicated stuff. I've played with the demo, but don't use it. But once you get the hang of it (do the tutorials ;) ), it's pretty easy to learn. Everyone who uses it swears by it.

If you plan on doing 3D work (I thought I remember you saying that), then SheetCAM won't help you. Take a look at MeshCAM for that.

ger21
02-11-2006, 07:12 PM
Also, start out slow. Draw a few lines in Rhino, run them throiugh SheetCAM to see what's going on. Then do a little more, a little more, and so on. Work your way up, don't try to do a complex project all at once.

HuFlungDung
02-11-2006, 07:15 PM
There is a lot to learn, no argument there. Perhaps it would have been better if you had picked up a textbook on the subject, to familiarize yourself with the general concepts before you went shopping for the software. I would sit down and write some simple programs by hand first, just to see the machine move, according to my input. Once you thoroughly understand how to write gcode, then you are ready for studying the output from a CAM and not feel totally vulnerable as a slave to your own computer.

Even OneCNC, while it is fairly simple to learn for those who are knowledgeable about the subject already, does not teach you how to read and write gcode. Whenever I read the requests of those begging for a preconfigured post suitable for a particular machine, I feel sorry that they are not seeking to understand the principles that underlie making a post work properly.

If you practise writing some gcode, and work from simple to complex via a series of your own projects, you will learn every detail required to make the machine work exactly correct. Then, CAM is quite simple to master.

At that stage, then you go shopping for CAM that will dependably simulate the program for you, so you don't have to wade through every line of gcode, instead, you will get a general overview of the results. You will want the software to give you a rendered model of what it cut, so you can examine it for blunders in setting up the process.

You will want CAM that makes it easy to make a new process, should you decide that you don't like how the first go round went. I often do this: create a program with my best guess about how it should be done, go out to the machine and run it, then I take notes about what I need to fix, about what doesn't work so good in the sequence I originally planned, and then go back and do a major revision. Using good, well-thought out CAM like OneCNC makes this whole scenario execute very quickly.

If the CAM you are using does not make this handy to do, then its the wrong CAM for you.

CNCRob
02-11-2006, 07:36 PM
Im not sure if they still do it or not but SheetCam used to offer a full funtional license for 30 days, If you email them they would send it out. Im not sure if you have aready did that or not.

saturnnights
02-11-2006, 07:47 PM
Im not sure if they still do it or not but SheetCam used to offer a full funtional license for 30 days, If you email them they would send it out. Im not sure if you have aready did that or not.

Hmmm... For some reason, I thought that what I downloaded was all that they offered... Depending on my next few days, I'll consider asking them for a 30-day demo, but I really need to make sure that when I get the demo, I'll be ready to use it!

saturnnights
02-11-2006, 07:53 PM
One thing I notice is that a lot of people ask very general questions that are nearly impossible to answer, like "What software should I buy?". But once they buy it, they rarely ask questions on how use it.

There are plenty of Rhino users here, and plenty of SheetCAM users as well. Ask very specific questions, in the appropriate forums, and you should get all the help you need. As for Rhino, there are tons of tutorials on the web. Nothing will help you faster than working through tutorials, imo.


If you plan on using SheetCAM, I doubt you'd hit Mach 3's 1000 line limit unless you're doing pretty complicated stuff. I've played with the demo, but don't use it. But once you get the hang of it (do the tutorials ;) ), it's pretty easy to learn. Everyone who uses it swears by it.

If you plan on doing 3D work (I thought I remember you saying that), then SheetCAM won't help you. Take a look at MeshCAM for that.

I don't know much at all about CNC - the more I learn, the less I realize I know! I'm a hands-on learner and like to get into something and see what it does. That's my problem right now - I'm trying to teach myself with these demos :tired:

The crazy thing about Rhino is that like most software apps, it helps to save as you go so that you can backtrack, but Rhino gives me that "hey, dumb-dumb, are you sure you wanna waste a save now?" message every time :p
That's why I figured that unless I have a version that I can use without fear of actually using it, I won't learn much. Once the licensed version arrives and is installed, I'll really start to bug the Rhino group! :cool:

I know that I said that 3D was my focus, but, as I keep learning, I am realizing that 2 1/2D may work for some things too. Sheetcam didn't seem like an option until just recently and I've been doing the demos in it too, but my objects have a lot of curves and the line limit may be a problem - I'll know this week for certain. But I did hit Mach 3's limit with my 3D stuff pretty quickly. It seems that 1500 lines is my average and these aren't complicated objects either... Hmmm...

But you'll see me around these parts a lot in the future - there's soooo much to learn...

saturnnights
02-11-2006, 08:10 PM
There is a lot to learn, no argument there. Perhaps it would have been better if you had picked up a textbook on the subject, to familiarize yourself with the general concepts before you went shopping for the software. I would sit down and write some simple programs by hand first, just to see the machine move, according to my input. Once you thoroughly understand how to write gcode, then you are ready for studying the output from a CAM and not feel totally vulnerable as a slave to your own computer.



What's crazy is that I went to the local bookstores and they carry NOTHING at all on the subject and their special order people couldn't help me either. And this was Borders and Barnes and Noble!
I'm seeing the benefit of learning gcode - just need to research that too - just another thing to research/study/learn...
It was mentioned that I should take a class - that's a pretty good idea!

HuFlungDung
02-11-2006, 08:19 PM
Here is a list. Once you find the titles you want, maybe you can find them cheaper elsewhere.

http://www.industrialpress.com/en/topics.asp?topic=MS

saturnnights
02-11-2006, 08:25 PM
Here is a list. Once you find the titles you want, maybe you can find them cheaper elsewhere.

http://www.industrialpress.com/en/topics.asp?topic=MS


Wow... Thanks - that's a lot to choose from!

I just with the local stores had some so that I could look at them and see which ones I liked. Some of these books are expensive and if they are a bad read, I'll be out of luck. Reminds me of my network admin days - buying a book without getting to look through it was risky!

HayTay
02-11-2006, 08:49 PM
:idea: Nobody seems to use them anymore, but, there's always the public library. A lot of colleges & universities will allow anyone to use their libraries, also. Most require you to be a student or instructor to borrow books, though. Still, a few hours here and there at the local community college should allow you to start filling in those knowledge gaps. Best of all it's free or nearly free!

HayTay

saturnnights
02-11-2006, 09:25 PM
:idea: Nobody seems to use them anymore, but, there's always the public library. A lot of colleges & universities will allow anyone to use their libraries, also. Most require you to be a student or instructor to borrow books, though. Still, a few hours here and there at the local community college should allow you to start filling in those knowledge gaps. Best of all it's free or nearly free!

HayTay


Oh man, that's a sore subject - my city just built a 30-million library...
I went there with my wife and asked for help finding the milling/CNC section. I don't think they had a book newer than I was old (40). The CNC was just NC - no computer stuff and the other books on milling in general were yellowed and had photos of equipment that if I owned would be worth a fortune today :cool:

Geof
02-11-2006, 11:21 PM
Oh man, that's a sore subject - my city just built a 30-million library......I don't think they had a book newer than I was old (40). The CNC was just NC - no computer stuff......

Don't worry the G codes and M codes are still (mostly) the same and I just checked a machine manual printed in 2001 which still refers to M30 as program end and rewind!

HayTay
02-12-2006, 12:09 AM
my city just built a 30-million library...
I went there with my wife and asked for help finding the milling/CNC section. I don't think they had a book newer than I was old (40). The CNC was just NC - no computer stuff and the other books on milling in general were yellowed

That's a bummer with the $30M library.

Do you have a local Vo-Tech School or Technical Community College? They should have more up-to-date material (or, at least, I hope they do!).

HayTay

saturnnights
02-12-2006, 11:58 AM
Im not sure if they still do it or not but SheetCam used to offer a full funtional license for 30 days, If you email them they would send it out. Im not sure if you have aready did that or not.


You know, I started to think about this and realized (yes, I'm buried/confused in all of this demo testing) that back on 1/25 I'd sent a request for the 30-day evaluation license. They never responded, so I've just sent another request - maybe this will get through?

Thanks!
Mark

Bluesman
02-13-2006, 11:21 AM
Oh man, that's a sore subject - my city just built a 30-million library...
I went there with my wife and asked for help finding the milling/CNC section. I don't think they had a book newer than I was old (40). The CNC was just NC - no computer stuff and the other books on milling in general were yellowed and had photos of equipment that if I owned would be worth a fortune today :cool:

Wow what a coencident my town just waisted 30 mil on a library that know body will ever use. You would not be from Bay City would you? I find it hard to believ any other town would find a need for that kind of money waist besides our town

Bluesman

saturnnights
02-13-2006, 11:37 AM
Wow what a coencident my town just waisted 30 mil on a library that know body will ever use. You would not be from Bay City would you? I find it hard to believ any other town would find a need for that kind of money waist besides our town

Bluesman

I'm from Akron, OH. I'll admit, the building is beautifu - but mostly empty, except for the computer terminals where you'll find people sitting doing things that they probably don't want their family members to know about.
But the book selection is embarrassing. It looks like they've stocked the entire library with junk found in old attics. They have a bunch of conference rooms too - those get used by local politicians for campaign meetings and whatnot. All in all, this library is a waste of tax dollars. We'll probably have a levy on the ballot soon to pay for heating increases - gotta keep those 50-foot, glass ceilings warm...

densman
02-13-2006, 03:37 PM
7 easy steps to CNC programing, a beginers guide.
David S. Hayden
www.haydenpub.com
I see copys of this on E bay, exellent book.

ZipSnipe
02-28-2006, 06:01 AM
Hey Saturn, I too have been downloading different software for cnc and cad. However I don,t have a cnc mill yet. I can tell you this that I have decided to take a cnc programming course at my local community college. Its a short 6 week course (one day aweek) it was only $169.00 I figured its worth it becuz you have someone teaching you on a live machine. You can touch it, you can see it work. As for software, my criteria was, I want to draw a flat outline of my project, which ever program allowed me to do this easily will be the one I choose. Turbo cad did this fairly easy. However it expensive. As for cam I still don,t have much of a clue and the same goes for the cnc software. But my point is look online at the courses offered by your local community college.

WhiteTiger
02-28-2006, 06:29 AM
Check ebay software section. I picked up a copy of turbocad 7 for around $20 just to have a good look at it. Liked it so much I ordered the most current version and haven't touched my old autocad 12 since.


Tiger

MIKE JEFFERS
02-28-2006, 06:36 AM
mark
have a look on the sherline site there's an excellent downloadable intro to cnc
programming
try the free programms ace converter/deskengrave/cnc simulator
dunno about free cad but autocad lite is cheap and good.
mike

saturnnights
02-28-2006, 08:16 AM
Thanks for all of the tips, guys... I have been looking into a local class for CNC and would really enjoy that, I think...

Mark