Ian, a couple of years ago I made a whole drawer full of gears, 30 to 240 teeth, for precisely the same purpose, but as I own a tiny combination mill (called UWG, google it), unfortunalely delivered without gears, but set up as CNC, I milled them with a stepper powered dividing head and home made software (EMC2 was not known to me then). It needed about 10 to 20 seconds per tooth, dry cutting, depending on the width of the blank and how fast I run it, not counting machine setup time if it was set up for a different purpose before.
I have the advantage that I can work with any material, so I made long lasting gears out of very tough hydraulic ram steel (containing molybdenum). With aluminum, brass or even plastic I think I could make it down to 5 sec. per tooth easily. I tried the same principle on my large mill after this and made some of the missing gears for my large lathe, just employing larger mechanical equipment, but same software and stepper driver. With the same setup it would be easy to make helical or bevel gear teeth, only by changing the 90° axes of the dividing head on the machine table. By the way, if you set up your lathe screws with electronic drives and EMC2, you wouldn't need any changeable gears at all anymore... Still, a 3D printer is a fascinating thing... Peter Ian W. Wright schrieb: > Gene, > > I've been considering cnc-ing my little 7 x 12 for a while > now but other things have had to take priority. However, I > can't see why you wouldn't just want to hang a little Nema > 17 motor direct onto the back of the cross slide screw. One > of the 60 oz/in motors advertised on Ebay for about $25 > driven by an 1/8 step driver like the little Pololu or > StepStick boards should give plenty of resolution and torque > - same for the leadscrew. I've used several of these motors > and they really have some grunt despite their small size. As > matter of interest, I recently knocked together a little 3d > printer - a Prusa Mendel - and one of its first jobs was to > make me several change wheels for my 7 x 12 to let me cut > the unusual threads I've been struggling with - like a 56 > t.p.i. for a microscope lens mount. Its only working with > plastic but its great to be able to print out things like > these gears in less than an hour for less than the cost of > postage if I had sent for one!! > > Best wishes, > > Ian > > ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
