Gene, On my 7x12 (Sieg C2 style), the mounting plate for the chuck is an integral part of the spindle, as shown here: http://littlemachineshop.com/products/product_view.php?ProductID=1341
Three studs/nuts hold the chuck to the lathe. There is another set of holes for mounting a 4 jaw, that shares one hole with the 3 jaw (6 holes total). I think of it more like a poor mans version of a D1-4. So, the only concern with braking resistors, is making sure that the part that is being held does not get slung out of the machine. I've been toying with the idea of using some 1/4" Lexan to surround the machine, so I can use flood coolant. I'm also hoping that it will contain any minor mishaps inside, instead of exploding across the shop. (My drawing/programming skills are very poor right now) > To change the subject a wee bit, does anyone have a link to someone selling > prefabbed optical pieces Do you mean like this? http://littlemachineshop.com/products/product_view.php?ProductID=1945 Kirk, I have two treadmill motors, 120VDC - 1100 watts, that I had considered using, but they both have the rotation listed as CCW. I haven't taken them apart, but I'm assuming they both have angled brushes that allow them to run in one direction. Are yours the same way?? If so, how well do they work when turning backwards? Oh, and Peter, I forgot to mention, your bunny multiplied... --------------------------------------------------------- Ne M'oubliez ---Family Motto Hope for the best, plan for the worst ---Personal Motto (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. On 10/11/2009 11:53 AM, Gene Heskett wrote: > On Sunday 11 October 2009, Kirk Wallace wrote: > >> On Sun, 2009-10-11 at 10:27 -0400, Gene Heskett wrote: >> ... snip >> >> >>> A far at the pair of 50's is concerned, they will also stop it fairly >>> quickly. Mine is maybe 2 or 3 turns from the full 2500 rpms, and some >>> might call that a little brutal, but I have been doing it for at least a >>> year with no ill effects that I have detected. A single 50 would >>> probably be fast enough, and certainly easier on the PM fields of the >>> motor. >>> >> That brings to mind, my Hardinge has a screw style chuck mount which >> seems like Russian roulette when using aggressive decelerations. >> > That might depend on how heavy it is, and how tightly it locks into home when > it is installed. Certainly a 50 pound or more chuck, unscrewed and still > spinning 1900 rpms, could do a lot of damage to both the person and the > equipment. My chucks are smaller of course, and normal change is to unbolt > them from a face plate, but that face plate is still screwed to the spindle > at whatever size thread is on a 7x12's spindle. I believe I took it off once > but don't recall now how I managed to get it loose as there is not a ready > method to lock the spindle in that little machine. > > That thought does beg for some method of locking it onto the spindle nose > though, and one that would not effect the accuracy of the mounting, so set > screws are probably out. As is double nutting, no space for the inner nut. > > > >> An A5 >> spindle is on my wish list. >> >> Another thought, for DC spindle motors, I've done a bench setup with a >> tread mill motor and Jon's PWM drive. With a minor modification, it >> worked very well. With its four quadrant feature, I suppose it could >> allow some axis capability. If one needs a new DC (or universal) drive, >> this could be a cost effective way to get one. Plus you don't need to >> monkey with an analog signal. >> >> > ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
