> From: gene heskett [mailto:ghesk...@shentel.net] > On 11/9/22 19:59, John Dammeyer wrote: > > I've been perusing through my Machinist Handbook (24th Edition) and > > googling with no real success. > > > > I think it was on this forum that the discussion came up on the holding > > power of R8 collets and how they > were essentially only useful for light machining. > > > IDK John, but that was the driving force for me to mount all my taps > small enough my spindle could turn them, in a 7/8" brass hat with a grub > screw on all 4 faces of the tap shank, running in a 7/8" r8 collet with > a notch cut in the face to engage a 4mm cap screw in the outer face of > the brass hat, thereby keying the tap to the spindle. Since the go704's > reworked spindle driver limits it to about 2 hp and low gear is about 4x > too fast, I'm stuck pecking the tap about 1/4 turn per peck for holes > above 8mm. It does get the job done, but I hear Jons pwm-servo current > limiting at about 18 amps, the motor iron quietly chirps... >
Hi Gene, I like your solution. Very innovative. I went the route of ER20 collets that are square in the bottom to keep the tap from turning. But they don't hold all taps because not all taps are consistent in shaft diameter so I really like your idea. Thank you. John _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
