MadCAM & OX CNC


#1

Hi All,

I’m asking similar questions on the CNC forums but I thought I’d ask here too.

I intend to purchase a pretty basic CNC kit based on the OX. I know enough about the mechanical aspect of the kit and could customise so that it perfectly suits my needs, but have decided to start with something that just works OOTB then create its replacement separately after I have the workflow dialed.

The part of the CNC process I don’t quite understand yet is the CAD->motion.
Most of the kits seem to be targeted towards people with no CAD experience, so the software seems to be more wizard based where you feed in a DWG and it gives very little control but spits out G-code.

I understand that CAD data needs to be interpreted by CAM software (ie. MadCAM) which will export toolpaths (assume these are g-code?) MadCAM is the software I intend to use since I’m already comfortable in Rhino and since I’m studying again I’ll get access to their education pricing.

I also understand the stepper motors need to be driven by ‘driver’ like the Gecko G540.

so just to clarify, my understanding of the dataflow is this:

Rhino->MadCAM->Toolpath file
Toolpath file->Mach3 (or other CNC controller software) ->Ethernet Smoothstepper -> Gecko G540 ->motors

is the Mach3 required? or does it just handle converting CAD into toolpaths?


#2

Mach 3 converts g-code into machine commands to be interpreted by the stepper motor drivers. Mach 3 is not specifically required, in fact some hardware may not be supported by it, though it is a pretty general piece of software with wide applicability.

There are other programs which perform the same function as Mach3. When you know which CNC machine you will use, ask the supplier what driver they recommend. They may even supply one with the machine. The program which generates the g-code will probably have a library of templates for a variety of CNC machines and you will need to ensure that you have compatible capabilities all along the line.


#3

Thanks AIW,

Found this - while looking for mach3 compatibility list - after reading your reply which really helped too. http://www.machsupport.com/wp-content/uploads/2013/02/Mach3Mill_Install_Config.pdf

Even went as far as explaining that a hardware controller (eg. smoothstepper) may remove some processing load off the mach3 workstation.

Sounds like I need an Ethernet daughter board for the file server (which lives in the garage with CNC) to connect to the network switch & the eth. Smoothstepper.
Then I can work in the office or remotely on laptop and network my gcode to he file server and set up the file on mach3 from there…

Also need to confirm that mach3 will work with my MadCAM files & is compatible with the smoothstepper:eth + Gecko G540 combo… pretty sure it is (found people positing online with similar setup) but worth me confirming…

Thanks again


#4

madCAM has many post-processors, which can easily be edited to work with any controller. I wouldn’t worry about the madCAM side of this project.

Dan


#5

Thanks @DanBayn ,

If I buy MadCAM do I need the mach3 software at all? Or can MadCAM drive the smoothstepper directly?


#6

You need controller software.


#7

Thanks mate, thought it sounded to good :blush:


#8

It kind of goes like this:

Rhino creates a model. madCAM creates g-code. Mach3 (or Fanuc, Heidenhain, Mitsubishi, etc.) read the g-code and convert that to machine movement.

Dan


#9

I built an OX CNC two summers ago, and it was quite fun. I ended up going with a TinyG CNC controller. I did not want to pay for CAM software, so I ended up using Fusion 360. Transferring Rhino models to Fusion was not as smooth before, but now Fusion will import Rhino models. CAMing in Fusion is really easy to pick up (there are help dialogue windows for everything).


#10

Yeah, Fusion is getting pretty popular. Pretty hard to compete with free. The advantage of madCAM (or Mecsoft’s RhinoCAM) is that you don’t have to leave the Rhino environment to create your toolpaths. Our main CAM software is WorkNC, and that requires exporting an IGES file, creating a “workzone” in WorkNC, then creating toolpaths. If the part changes, you pretty much have to start over. If you can stay in Rhino, then you cut out a lot of steps, and changes are easy.

Dan


#11

[quote=“DanBayn, post:10, topic:42191”]… you cut out a lot of steps, and changes are easy.
[/quote]

That directive has informed almost all of my decisions on this project. Less time hacking, more time creating…