RepRap = also a milling machine

I just visited a conference about the launch of GPLv3. There was a very nice ambience. People I talked with were very interested in the possibility of the RepRap, and about it being a project under the GPL.

The Dremel(TM) toolhead

As everyone related to the project has envisioned, the RepRap will become a very versatile machine! Not just because they expected this, but because all of us had different plans with it. I wanted to actually mill PCBs… and this now seems very possible. The RepRap’s standard toolhead is for extruding plastic. Nice to have to make many useful things. There are several things it’s good at. It can make things that are not possible with the industrial standard of injection moulding. In terms of shapes it can create a hollow object consisting of one part. It can contain other components if its assembled during build. It could potentially reinforce the plastic with glass fibers, ceramics or a metal frame (to make for a composite material), this makes it stronger than any plastic moulded object could ever be. It could vary in color and still be made in one piece (adding the color pigments CMYK-style) as we extrude it, etc. Using edding markers of various colours this seems likely to be possible. But a lot of testing needs to be done (as always!). In summary, A lot of posibilities for plastics.

But still… sometimes the material requirements require something other than just plastics…

We needn’t stick to using plastic. If we want to be able to use any wood, metal, sheet material it would be nice to be able to mill or engrave those using digital models! This is what I’ve been working on for the last two days. Here are some more pictures:

Milling more!

My first RepRap engraving/milling result!

I ended up writing the GCode parser and control software myself. The ReplicatorG actually did a good job, but it wasn’t transparent to me what it did. Yesterday, after an evening of coding I could interpret and tidy up G-Code on the fly, control the machine from my program and do this in an interactive way. It has a command line with aliasses for G-Codes, and smart AutoCompletion and a history of entered command. I intend to release this code soon. Amazing what a modest 200 lines of php code can do 😉

Mechanically, my innovation is to sharpen my milling head through automatically moving it to a position where a sharpening block is placed. Initial tests showed that this made it sharp and pointy. If this proves successful, you can use a 50 ct. drill instead of a 10 euro tungsten carbide milling bit. It can automatically be kept sharp so it might outperform one that wears out slower (in terms of price/performance). Besides, I don’t want to spend the money if this doesn’t fail. I’ve bought enough things ‘just in case I need it’ already 😉

I intend to automate the process from Inkscape to actual workpiece and make it more transparent and user-friendly. But I have to go through the tedious manual process a couple of times to see HOW to do this in the best way. Perhaps I’ll make an interactive (AJAX) graphing app that can also initiate the machine control and visualize where it is in real-time…

We can only see a short distance ahead, but we can see plenty there that needs to be done.

— Alan Turing