The spindle brake is usually something that holds the spindle after stopping. I believe my Bridgeport has a ratchet which engages a gear. Obviously, I don't want to try to use that to bring the spindle to a stop.
The reason you need a braking resistor is to dissipate the back emf from the motor after a rapid decel. If you don't perform too rapid of a decel, then the braking resistor is not required. I would imagine, from all I have seen, that rigid taping would usually require a braking resistor, even if the decel was caused by drag on the spindle. I typically pick a VFD one size larger than what is required to help mitigate the need for a braking resistor. If the load is high inertia, or a heavy load, I will go 2 steps up in size and then still use the braking resistor. ________________________________ From: Jim Craig <jimcraig5...@windstream.net> Sent: Thursday, February 2, 2017 3:29 PM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] VFD recommendations - braking resistor vs mechanical brake. On 2/2/2017 9:13 AM, John Thornton wrote: > I also have an Automation Direct GS2 on my BP knee mill and rigid tap > with it (need the braking resistor). > > JT John, That is an interesting point. I am getting ready to add gear tooth sensors on the bull gear so I can rigid tap. I don't have a braking resistor on my drive. Currently the mechanical spindle brake engages when the spindle stops via a pneumatic cylinder. To be honest I am not sure if it would engage during a spindle reversal as I don't do that currently. It probably would not. Does the rigid tapping cycle stop the spindle or does it do a reversal without stopping? M3 M5 M4 M5 or M3 M4 M5? I figured that the drag from tapping would stop the spindle pretty quickly without the resistor. I would like to hear more about your experience with this situation. Thanks, Jim ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot Slashdot: News for nerds, stuff that matters<http://sdm.link/slashdot> sdm.link Slashdot: News for nerds, stuff that matters. Timely news source for technology related news with a heavy slant towards Linux and Open Source issues. _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Emc-users -- Enhanced Machine Controller (EMC) - SourceForge<https://lists.sourceforge.net/lists/listinfo/emc-users> lists.sourceforge.net This list is for users of the Enhanced Machine Controller (EMC). Topics include how to obtain, install, configure, and use EMC, as well as other general EMC related ... ------------------------------------------------------------------------------ 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 Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
