On Thursday 02 July 2020 15:10:45 Chris Albertson wrote: > Gene, > > Have you measured the torque needed on the worm gear while cutting? > Clamp a lever arm to the shaft and measure the force with a spring > scale. The worm reduction multiplies the torque by the number of > teeth on the wheel. You may not need a powerful motor. In any > case, step-one is to understand what is required. > Motor and driver I already have Chris, its a 3NM 3 phase stepper driven servo. With an 8mm d-flatted output shaft.
What is unk is how much drag on the worm, making it hard to turn when its bucking the force of a cutting tool. So 2 things concern me, first being will it still move when there is a carbide tool ripping off a chip 50 thou wide and 5 thou deep. And how do I handle a 90 kg head if its going to hit the table motor first while the hoist is running a foot a second. The latter demands the motor be very easily removable just to prevent that. Set the BS-1 on the table and mount the motor by plugging in its connection to the gearbox shaft, and tightening the clamp. If the BS-1 needs to be tilted, loosen the motor/gearbox, tilt the head, move the motor/gearbox to a suitable angle where everything clears and tighten the clamp again. Home it. Home switch will be on the chucks backplate. Motor is a std nema 23 face except its an 8mm shaft, not a 6.35mm. > On Thu, Jul 2, 2020 at 10:03 AM Gene Heskett <[email protected]> wrote: > > On Thursday 02 July 2020 10:50:04 andy pugh wrote: > > > On Thu, 2 Jul 2020 at 15:02, Gene Heskett <[email protected]> wrote: > > > > Problem #2 is the lack of an independent locking method for this > > > > flanges rotation which is also the worm backlash adjustment, > > > > > > Maybe something like picture 4 here: > > > https://www.cnczone.com/forums/uncategorised-metalworking-machines > > >/172 314-cnc.html > > > > That is fairly similar to whats already in the BS-1, except the BS-1 > > has only one locking screw. So thats pretty close to what I am > > looking at, except the motor, unless it has a builtin gearbox, is > > obviously too puny to turn it under a good cutting load. I intend > > to have the torque to move it while cutting. I've two tables > > already, but neither can be moved when a cutting load is applied. > > It took me half a day to make a big drill bit 2 years ago when I was > > building in a wheelchair ramp, a job I should have completed in 30 > > minutes or less because a 270oz/in motor directly on the worm > > couldn't do the twist while cutting more than 2 thou deep per cnc > > loop. Very slow going on a 3 flute bit. Life's too short to put up > > with that BS. > > > > Another possibility is a right angle worm drive gearbox on a > > circular mount, so the motor could be loosened and rotated to clear > > stuff regardless of the tilt. > > > > Something like: > > < > > https://www.ebay.com/itm/Worm-Reducer-NMRV050-19mm-Input-Shaft-Gear- > >Ratio-Speed-Reducer-60-1-100-1-Ratio/193329956155?_trkparms=aid%3D555 > >021%26algo%3DPL.SIMRVI%26ao%3D1%26asc%3D225074%26meid%3D4f3a76f9cf814 > >2fcb1041038832557eb%26pid%3D100752%26rk%3D5%26rkt%3D20%26mehot%3Dco%2 > >6sd%3D174176794081%26itm%3D193329956155%26pmt%3D1%26noa%3D0%26pg%3D20 > >47675%26algv%3DSimplRVIAMLv5WebWithPLRVIOnTopCombiner&_trksid=p204767 > >5.c100752.m1982 > > > > > > Shaft adapters would need to be made, and a rotate able mounting > > centered on the worm shaft would have to be made but thats a heck of > > a lot simpler than my original idea. Make the whole thing quickly > > unpluggable from the side to protect it from missfires of the hoist. > > > > What do you all think, do you see any problems I don't in my > > enthusiasm? > > > > Thanks all. > > > > Cheers, Gene Heskett 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) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
