This page is in response to some questions that arose via Email on how I have TurboCNC configured. But initially I do want to clarify a few issues that will hopefully save some time on all parts...

a) I've only built this one mill and there are many other sites by folks that have built a lot better mills than this one, so definitely look at as many designs as you can as your designing and even while your building. 

b) I only evaluated a couple of CNC software packages, and found DAK Eng's TurboCNC to be the easiest and definitely the most cost effective. As a hobby type user I'm not in a position to shell out 3 figures on something as speculative as software to do just one function on a project that is already near the limit of what I can understand. I did register my copy for the whopping sum of $20 and will register the next copy for my next mill, even though I doubt that both will ever be running at the same time.

c) I don't think that there are any rules to how you orient your mill, the layout I followed is what I consider a "Fixed Gantry Mill", but again I'm just going by what I've seen at other sites. As you're reading through this it may seem disjointed, as I'm posting common answers to questions that I've addressed via Email to this point and will just forward the URL in the future if the info is already posted. So if your here because I replied to your question with a URL and 3 or 4 words, I'm just trying to save some time...

This the final layout of my mill and how it seems to work the best in the course of experimenting and debugging problems that have come-up.

I know for a fact that in previous pages early on I had referenced the base table as the X-axis (which it was, but it's distance of travel was far less than the top Gantry and it lent itself better to be re-programmed as Y)... As the Z axis is generally accepted as the plunging or vertical axis, it has stayed as such.

The polarity or direction of positive & negative never even occurred to me until I tried to mill my first piece and my name came out backward as if seen in a mirror. So I had flipped the terms around on the offending axis and on the next attempt it came out forward.

Once I had this stabilized as a fixed orientation, it became second nature and I would mentally reference this as I created toolpaths to envision the mills movement and watch for "Bad Paths".

I call them bad paths, in that it is a point to point co-ordinate movement that typically will cross or cut through an area that was not to be cut.

Along the subject of toolpaths the following are not major revelations but they are worth noting.

The toolpath is a 2 dimensional point to point co-ordinate system that is drawn as a "hair-line". The diameter of the cutter (say 1/4" or 0.250" )will straddle the toolpath cutting the radius (1/8th" or 0.125") on both sides of the path...

Sure, that is obvious, but it has to be taken into account that lettering, pockets and other artifacts have to be either  over (or under)-sized by the radius value to ensure that they actually are milled to dimension.

Mill Up-Grades Spring 2004

The actual work station takes up remarkably little room... 

The PC is located below the bench and the Mill, Monitor, Keybrd and Mouse (never used...) huddle together as if to watch each other's backs.

In an effort to gain larger part sizes, I realized I could cut back the table by close to 3".

There was close to 5 hours of farting about and adjusting every nylon runner and test fit the smaller table... 

Eventually it occurred to me to scrap the solid steel stepper to lead screw coupler.

The rubber coupler that solved all my problems in under 10 minutes was a 4" length of 1/4" air hose, liberated from the fuel line on the Oil-Fired Melting Furnace.

The hose was driven over the lead screw with a hammer and ring clamped to the Stepper shaft. 

I can't see why I wouldn't use this for all future Light Duty mills...

The OEM'd Dremel has had some modifications as well. (Curiously I emailed Dremel offering a sponsorship spot on this site... As I'm still using the original Craftsman OEM, I assume their quite busy @ Dremel Corp...)

The casing above the motor has been cut open to allow better air flow, aided by a 486 Cooling fan. A series of slots were cut below the motor where the hot air is exhausted.

The air flow down & out is to avoid drawing in foam debris and clogging the bearings or motor. The tool is removed, disassembled, cleaned and lubed after 15 plus hours of run time. 

The other reason I opted to reduce the size of the mill-table as that I never did need to clamp any work pieces with the grooves.

Double sided carpet tape is the ultimate in utility and cost. The other bonus it that I'll never break or bend a cutter on a clamping fixture due to an errant toolpath.

This plaque measures out at exactly 10" in diameter.

It's not fastened to the table as I'm pretty anal about symmetry and things meeting @ right angles...

The mill has produced close to 40 pieces that ranged from under an hour run-time through to 6 hour marathons where you don't leave the machines side for fear that all the work become un-done by a stray flake of debris wrapping itself round the cutter.

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