Noob question

[PBfan]

I'm new to the CNC world. And have some questions about CAD - CAM - and G-Code.

1. What type of work is there, transfering from CAD to CAM software? It can't be as simple as importing, can it?

2. I'm using Inventor right now. Is there a CAM program that meshes with it better than the rest? IE. Less work for me when converting.

3. If there isn't. What is a good CAM program?

4. I read something about a program that reads G-code, and makes a virtual 3d model so you can virtually inspect it for any flaws. Is that included with most CAM software?

My needs will one day be small production runs of parts I've designed. So keeping accuracy is important. And will be taking all the steps I can to make sure my Mill is set with the most accuracy.

I'm sure I'll have moe questions later(ha ha).

Thanks for the help!!
-Raymond

[RASPNC]

You can simply import dxf files into CAM software which you can visualize in a CAD type environment for example top, front bottom bacl left and right views. You can also import 3D wireframes however I haven't done this.

You then have to apply toolpaths to to the shapes created by the dxf file.
This is quite easy an easy task but it may take you a few days to get the hang of it.

There are several variables and constants you will have to set up within the CAM software before you produce the G-CODE such as:

Tool dimensions for each tool your machine is to use, this is so that the software knows how far to offset the centre of the tool and position it in the Z axis (as all tools/cutters are different sizes).

The machining speed. (This may be tool Specific or may be a generic speed or a combination of both.)

Spindle Speed. (This is usually specific to the tool used and material to be machined
)

I havent used any CAM software for a few years so there may well be a package that is more automated and can create toolpaths from a 3D CAD model (especially for complex 3D >3 axis machining) , however I expect there will nearly always be some human input required when creating toolpaths such as direction of cut and order of cut (please correct me if I'm wrong) Its hard to get a computer to automataically prepare for every possible maching complication that you may encounter.

I have worked in the furniture industry so It was always important for me to decide which way a cutter would cut around a piece i.e clockwise or anticlockwise as it made a differnece to the cleaness of a cut due to the grain direction (which the computer could not automatically account for).

The software I have used was (Licom / AlphaCAM) this had the ability to show a virtual 3d model of the part to be machined. It would also show an animation of the part being machined, this was usefull but I wouldn't always trust it.

I would send the g-code file to a machine operator that used another program to control the machine, he could visualise the g code on a screen using 2d views, he could then make small changes by clicking on the toolpaths and changing settings.

A good CAM program is one that does what you require. It would depend on the complexity of the parts you wish to produce along with other factors like the limitations of your machine.

I would check out some of the different CAM package websites. There is probably a lot of advice on this website showing peoples personal preference in other forums on this website.

Hope this of use to you.

Nik

[PBfan]

Thanks for your input!

I will be doing 2 "types" of machining. One is basic parts that are not made to be visually pleasing(basic shapes). The other, are very visualy pleasing parts(complex shapes). That are very detailed. My very detailed may be different than others. I'm not sure.

I'm sure that the new machines I'm going to be purchasing, are capable at what I need done.

I may try and fins some freeware CAM software(if there is any) just to mess with before I'm ready to start any metal work.

Thanks again!
-Raymond

[RASPNC]

I think a lot of people tend to use mach3 and its good value for money.

If I understant correctly, Mach3 can be used to generate G-Code and to control your machine.

You may want to check out the following links.

There may be a demo version you can download and try out for free.

http://www.machsupport.com/artsoft/p...s/products.htm
http://machsupport.com/forum/index.php

[PBfan]

Thanks for the links. Didn't see any trial offers. It does say mach3 is available for registered users. But I'm thinking that's people who registered older products, not the for registered forum users.(Oh I wish).

I've been told by the company who's mill I'll be getting, that Mach3(Mill version) is best.

I'll do a search on freeware, hopefully turn up something. Just to see what it's going to involve, converting to CAM/G-Code.

[RASPNC]

As you will prob end up buying Mach3 in the end I would try the demo of Mach2.

Here is a link so you can download the demo.
http://www.artofcnc.ca/Mach2R6.11N.exe

It allows you to produce up to 1000 lines of G-Code.

You can prob do most of the things Mach3 can do using Mach2.
I think Mach3 is just a bit more stable and has a few extra options.

At least you'll be able to get a feel of how the software works.

Regards

Nikki

[PBfan]

Hey. Thanks a lot! I never thogt of looking for Mach2 demo(Go figure. lol).

I'll give this a try. Should answer a lot of my questions.

Thanks a lot!

[PBfan]

Is this the basic process of design to machining?

1. Draw a part in CAD
2. Import into CAM
3. Check the CAM file for any issues with the conversion. Fix them if there are.
4. Output G-code from the CAM File
5. Use a post processor to check the code.
6. If the codes looks good, import it to your CNC computer, and start throwing chips?


I may be wonrg on what post processor is. Since online checking gave me nothing.

Also. I'm going to play around with Mach2(Thanks Nikki) and use some manual g-code to learn what everything does. What are some other useful ways of learning G-code? (Reading here, I understood taht learning manual g-code will greatly help when learning CAM).

Lastly(Althohg I doubt my last question for now. ha ha). Which is the limiting factor for the # of g-code lines? The CAM software or the CNC software? Or both?

Thanks in advance!!! As I'm trying to figure out just everything I need to be able to properly start making parts.(Already have CAD software).
-Raymond

[Al_The_Man]

. What are some other useful ways of learning G-code? (Reading here, I understood taht learning manual g-code will greatly help when learning CAM).

If you want to play around with G code and see the results, try a free simulator.
If you crash it won't do any damage.
http://www.cncsimulator.com/
Al.

[PBfan]

Thanks!

One other question I forgot to add. Where are some good online courses for mostly CAM(That's where I learned to use Inventor.)? It's probably got to be more specific to what software. But I haven't chosen what I want to use yet. And for what I paid online for courses. I'm very pleased, since I can do anything I need to in the CAD program.

Edit: Thanks for the simulator, Al. Before, G-codes scared me(very new to CNC). Looking at a huge list of things that don't make sense to me. But going over them all, and seeing what they do. It's really helpful.

[ger21]

Don't download Mach2. Go straight to Mach3. Any Mach3 download will function as a demo, and become a full version with the addition of a license key (when you purchase it).

The demo has the following limitations. http://www.machsupport.com/MachJargo...de_limitations

1. Draw a part in CAD
2. Import into CAM
3. Check the CAM file for any issues with the conversion. Fix them if there are.
4. Output G-code from the CAM File
5. Use a post processor to check the code.
6. If the codes looks good, import it to your CNC computer, and start throwing chips?

The post processor is what tailors the g-code to your machine when the CAM software creates it. different posts are used for different machines.

You use a simulator to check the code. Some CAM packages include them, and there are other standalone packages available.

Lastly(Althohg I doubt my last question for now. ha ha). Which is the limiting factor for the # of g-code lines? The CAM software or the CNC software? Or both?

The control software would be the limiting factor. The Mach3 demo is limited to 1000 lines, but I don't believe there is a limit once it's registered.

[ger21]

One other thing with Mach3. If you're just playing around with it and won't be running a machine, then install it in simulation mode. During the install, towards the end, You'll see a checkbox that says "Install Driver". Uncheck it. By not installing the driver, you'll avoid any possible hardware issues. It will still run the same though, and won't tax your sustem resources nearly as much.