Newbie- What tools generate G-Code

[eskimobob]

Hi all,

New to CNC and EMC but have now successfully got EMC2 (from Ubuntu Hardy Heron live CD) controlling an old Denford milling machine. I am probably doing this in reverse order but now I have it running, I need to be able to create G-Code files.

Could anyone tell me what programs I would need (preferably GPL Ubuntu) in order to capture a design and convert it to a G-Code file for milling? - I have read about Qcad but do I need another program to convert DXF to G-Code?

I'd like to be able to mill simple shapes in vero cases to begin with but longer term I plan on routing PCBs too. I know there is another forum for that so I will ask about converting Gerber files to G-Code elsewhere.

Many thanks.

[chazmtu]

Hi Eskimobob,
What your looking for is a cam(Computer Aided Machining) program. They allow you to import or draw dxf(and sometimes more) files and decide what machining operations you want done. They also generate g-code. My g-code interpreter is separate from my design machine. Were you planning on using one machine for everything? I use CamBam for windows but there are many others out there.

Chuck

[eskimobob]

Hello Chuck,

Thanks for replying. CamBam looks very interesting - I will investigate further. As it happens, I had been looking at PCB Isolation routing on brusselsprout.org.

My linux box with EMC2 on it is in the shed so I am quite happy to use another program indoors to generate the G-Code (Windows or Linux). I hope to keep it low cost though as it is for hobby use.

All the best

p.s. What program would you recommend for CAD work then in order to create the DXF that I push through CamBam? - Or, will CamBam allow me to draw objects too??

[chazmtu]

CamBam will let you draw basic shapes like circles, arcs, polylines and import ttf fonts. It has a lot of other functions too as well as addons and scripting for custom shapes ect.
For the more complex drawing I use Inkscape which can save dxfs but only in the linux version. Recently though I ordered CoralDraw which I hear many good things about from people here. It's expensive but If your a student you can get a big discount.
What kind of machine are you running EMC2 on? I run Turbocnc on an old laptop with the minimum requirement for EMC2. I was thinking of switching but don't want too much of a hassel.

[eskimobob]

Originally Posted by chazmtu What kind of machine are you running EMC2 on? I run Turbocnc on an old laptop with the minimum requirement for EMC2. I was thinking of switching but don't want too much of a hassel.

I'm running EMC2 on an old Desktop machine P166 (IIRC). I started from scratch with it using the Ubuntu Hardy Heron EMC2 Live CD - Initially I had trouble getting it to install but it turned out to be a lack of RAM. I had 128 Meg installed which was more than the 32 Meg minimum specified however it seems that the installation required more to work reliably. I added in a couple of spare 128 Meg sticks (making 384 Meg total) and installation was then smooth as silk.

Surprisingly easy to modify the .HAL files when connecting my stepper drives, home and limit swithes to the parallel port pins too.

Hope this helps.

[cyclestart]

Originally Posted by eskimobob - I have read about Qcad but do I need another program to convert DXF to G-Code?

Qcad has a companion program called CamExpert. It is aimed more at uses like plasma. The demo times out every 10 minutes.

Synergy is cad/cam that will work with mills, The 2D cad portion is free to use and powerful and complex compared to Qcad. It has a menu item for DXF export but I have not been able to make it work. Possibly this feature is disabled in unlicensed versions. Who knows ? The difficulty of finding this type of information without directly contacting the company is a downside of this software.

I have been testing out Sheetcam TNG recently and find much to like about it. It's 2D general Camware and does not create drawings.

I'd like to be able to mill simple shapes in vero cases to begin with but longer term I plan on routing PCBs too. I know there is another forum for that so I will ask about converting Gerber files to G-Code elsewhere.

Have you checked out Eagle ?
http://www.cadsoftusa.com/
Being electronically challenged I know it exists but not much more.

[eskimobob]

Originally Posted by cyclestart Have you checked out Eagle ? http://www.cadsoftusa.com/ Being electronically challenged I know it exists but not much more.

I currently design PCBs using Easy-PC (I bought the full version for work use) and therefore I'd like to be able to take the standard gerber output and convert to G-Code. Having read on brusselsprouts page, it seems that Eagle can import Gerber files and then create G-Code so I may well end up using Eagle in some way after all.

There does seem to be a SourceForge Gerber to G-Code project but it still seems to be in the early stages.

[eskimobob]

Just realised that my Easy-PC program can output DXF of electrical layers. Have done so and opened it in CamBam and I can see something reasonably sensible but not sure what to do next - looks like I need to investigate the CamBam forums...

[chazmtu]

Just realised that my Easy-PC program can output DXF of electrical layers. Have done so and opened it in CamBam and I can see something reasonably sensible but not sure what to do next - looks like I need to investigate the CamBam forums...

Does the DXF give you just the trace outlines or toolpaths for milling? If its just the outlines all you need is highlight the traces and try 2.5 machine op. It will let you choose how deep to mill, which side and how far back to mill it. I think theres a tutorial on the cambam site for each machine op and their functions.

[eskimobob]

Thanks Chuck. Easy-PC has several options for DXF output and two of them give trace outlines which look great in CamBam. Selecting 2.5D and then generate toolpaths does work (although I need to read more). Unfortunately the traces are shows as multiple segments so it looks like it would take absolutely ages to highlight each segment before chosing 2.5D and then generate tool paths on anything but very simple PCBs. I think I will investigate Eagle import/export functions next.

[Tony Mac]

Hello Eskimobob,

Have you looked at Cut2D which will convert DXF to GCode. There are users running the code through EMC2 and I believe it runs on Linux Ubuntu, although have not actually done so myself.

More information + a Trial version on the Vectric web site.

Some interesting projects on the Forum

I hope this might be of interest.

Tony

[stratcat50]

There's a fellow in Germany with a program called 'dxf2gcode'. It's still in progress but working nicely so far. I've been converting Inkscape DXF files for use in EMC with good results.
The site is in German but the program is in English. No installation needed, just run it.
http://www.christian-kohloeffel.home...dxf2gocde.html