On Sunday 20 May 2018 00:09:05 jeremy youngs wrote: > Gene, I was perusing eBay and found this, thought of you. > 323251704661
What I've already done basically, and too much $. I have a 1 hp treadmill motor, driving a 3" polygroove pulley on one end of a jackshaft for a 3/1 reduction, and the jackshaft sits in about the same place as the OEM motors shaft would be but the pulley's are a different groove profile with much less of a tendency to jump a tooth and that end of the jackshafts bearing frame setup with a jacking screw to immobilize it so it can't find room to jump a tooth. The lower pulley has had a couple teeth added just to get more teeth of the belt engaged. And I've put the metal gear kit in the headstock. With that branch of a weeping willow they call a compound gone in favor of a block of cast iron the same height, and tapered gibs, its a whole new machine that can actually be called a lathe. But the ball screw for the x axis isn't at all well shielded so its collected some swarf in the screw/nut, making a crackling noise. Thats one of the reasons I sealed that whole area up on the sheldon, and the same size ball screw is running the Sheldons X. On the 7x, the X motor is direct drive on the rear, making it very hard to shield the exposed screw from swarf since the teeny cross slide exposes it. On the sheldon, the x motor is on the back of a 1/2" thick plate bolted to the front of the carriage, and a 2/1 reduction in cogged belts and pulleys drives the screw. Limited in room behind this replacement apron, its a short nema 24 motor I intend to make a damper for eventually as theres about 50 thou of clearance between the bed face and the back shaft of that motor, and raise the psu voltage to the driver, but its the shoemakers kids story, the 30" IPM I'm getting there seems to be sufficient. When making the studbolt to mount the drill chuck to a Tee nut on the mills table yesterday, I used g76 to cut the 1/2x20 thread to fit the chuck, then moved closer to the ER40 to cut the 3/8x16 for the Tee nut, I was forced to use an I setting above .350" to keep the drive line outside the 1/2" section. A snap move at the left end with a L=1 because I didn't want to damage the 1/2" section with the right edge of the HSS tool using a short E, but at 200 revs it was plenty fast enough and cut a good thread. But I calculated the length wrong and when it hit the bottom of the Tee nut, so I had room for a stack of washers under the chuck, a fact that actually stiffened up the chuck mount. But that idea may be a time waster unless I mount the brass "hat" in the sheldons ER40, and put a dimple in the end of it with a center drill to guide the drill bit to get better centering on the drills entry. With 50+ of them to do, that extra operation is gonna put plenty of mileage on these old diabetic legs. So I'd better survey the kitchen for a couple bread pans for in/out containers and do them all in one setup. However, I do appreciate your thinking about me and "TLM". I really should change its hostname to TLM, a better fit for "The Little Monster" it's turned out to be. :-) Thanks Jeremy. Take care now. -- Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
