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View Full Version : Cheap Lathe CAM or manual g-code?



m_c
12-10-2011, 12:29 PM
I'm needing something to make some simple parts beyond the Mach Wizards, but can't really justify spending lots of money just now (holiday and shiny bike bits have drained funds!)

I've got plenty options for creating DXFs, so that's not an issue, but converting them to G-code is.

Looking at what I'd like to make just now, I could probably just about get away with writing the g-code (mostly a mix of centre holes, tapers, and reduced sections)

So what are the options?
Manual G-code?
But how does that work for doing multipass tapers/reduced sections?
Cut and paste the various Mach wizards together?

Simple CAM?
I've already tried Lazyturn, but the lack of finishing pass puts me of.
I see mention of CamBam, but they've only recently added a turn module.
Any others suggestions?

Jonathan
17-10-2011, 02:03 PM
If you want a free option...

I've occasionally used my mill as a CNC lathe, like this:
http://www.youtube.com/watch?v=4wGDMSiZpyg

(It was just a test, I don't actually want to make chess pieces!)

I did the code for that piece by:
Drawing it in CAD program.
Contour the profile and join up the ends to create the toolpath
Export as dxf then open in Cambam (the version for milling).
Use 'engrave' funtion in cambam to create toolpath that follows the line.
Change the lathe axis definition in Mach3 to X and Y, ignor Z.
(Optional) Open code in notepad and use find & replace to remove any Z moves to stop it pausing.

There is one problem with this method which may be significant. If you just draw the toolpath by contouring the part then you don't compensate for the radius on the cutter. So clearly if the part is just aesthetic this may not matter, or if the tool has very small radius/sharp point or if the angle of the surface you are cutting from the axis of rotation is small the error is less significant.

Cutting and pasting wizards sounds fine.

m_c
17-10-2011, 04:27 PM
I've been having a play with Cambam, and it does have potential.

From the hour or so play I had on it, it looks like it will be able to produce the majority of the external machining code (i.e. no boring/drilling/i.d. turning) I need for now, and for what internal machining I need, I should get away with the wizards/hand writing the g-code.

I've now just got to decide how to mount the drill bits that I'll be needing...