Engraving or machining on a flat surface is the norm–all CNC’ers figure out how to do it in short order.  But what if you want to engrave or machine on an irregular surface?  Let me show you what I’m talking about:

Engraving or machining on irregular surfaces is hard…

Engraving or machining on irregular surfaces is hard.  You could try a spring-loaded tool holder–companies like 2linc offer them:

Spring-loaded tool holder from 2linc…

They work pretty well but at $345 or so they’re not cheap, especially for a one-off project.  Their travel is limited to about 0.4″ and they are rpm limited to 10,000 rpm, which is fine for most CNC Mills and slow for most CNC Routers.

You could try to create your CAD geometry to fit so your machine need not be aware, but that’s pretty painful and time-consuming as well.  Besides, just getting an accurate CAD model of the existing surface you want to engrave may not be all that easy.  Pretty soon you’re busy trying to do some kind of 3D scanning to make it work.

There has to be an easier way!

And there is–you need a little software utility I recently came across called “G-Code Ripper.”  The GCode Ripper is a cool free CNC utility written by a guy who calls himself “Scorch.”  It does all kinds of nifty things including the 4th Axis Wrapper stuff you may also find useful every now and again.  A 4th Axis Wrapper will take flat XYZ gcoded artwork and wrap it around a cylinder.  It just creates an easy way to machine things onto a cylinder.

GCode Ripper does all that, but it can also arbitrarily warp your 2 1/2 D GCode onto an arbitrary surface, such as the mouse pictured above.  It does this by creating a “Map” of the surface using a probe, which it then uses to “warp” the flat gcode to fit the surface.  Here it is in action in this YouTube video:

[youtube width=”800″ height=”540″]http://www.youtube.com/watch?v=dzX0JXX5iCc[/youtube]

GCode Ripper demo…

Give GCode Ripper a try.  It’s fun, it’s free, and it just might solve a very difficult problem for you the easy way.