On Tuesday 29 March 2016 03:25:55 Neil Whelchel wrote: > Hello everyone, > Thank you very much for your comments and suggestions. To me the tap > is not the issue, a broken tap in a hole IS an issue, so it is all > about not breaking the tap if the spindle faults out. As long as the > axis stays slaved to the spindle, the tap can be removed by hand. > There is not much point of restarting on the same hole, as that one > can be completed by hand tap if needed. However, having just said > that, I have found that since the axis slave operation starts on the > index mark of the spindle encoder, I can actually tap a hole again, > and with quite impressive results. I will look at motion.feed-inhibit, > it looks promising. The docs say that it allows synchronized motion to > complete, but it is unclear if it will work in the case of manually > backing a tap out of a hole. I will report my findings. Thank you, > -Neil- > I agree with 90% of that. Restarting the operation here at the WOWElectronics shop has generally not been practical because the tap has slipped in the chuck, or the whole chuck holding the tap has turned in the boring bar type holder I use to hold taps on the carriage of my toy lathe. I lack the ability in a tap holder to grab the square rear end of the tap in a tool holder and positively prevent its moving. If I had that problem solved, and I drive the tap to the starting position in my G33.1 wrapper, then a rehoming of the lathe should put it close enough to restart the hole if the spindle faults because the tap is bigger than the spindle can do w/o bogging down. Editing the wrapper for a smaller peck so it doesn't trip off again of course.
Much the same problem exists on the G0704 as there is not a precision way to hold the tap there short of welding it into a tool holder, which would of coarse anneal the tap into some about as strong as a peep. I broke a 3mm.5 tap the other day because that POS chuck that came with the g0704, with its taper mount, had so much runout it forced the tap sideways and snapped it off. I measured the tapered section, finding the taper had a runnout of about 3 thou, but so did the chucks rear socket, so by knocking its adapter out, turning it a bit and driving it back in, I finally arrived at about 2 thou of runnout on a 6" piece of 1/2" A2 drill rod, and it seemed to be repeatable, the R8 it was being held in was pretty true. Pretty good considering my first measurement of that runout was in the 55 thou range immediately after I broke the tap. Measured on the remains of the tap stickout. I was by myself and the shop air was pretty blue for a while. I have searched the net, but have largely come up empty when looking for a tap holder that actually grabs the square on the butt of the tap. If I was a tool maker trying to design such a beast, I would first try to convince the tap makes to standardize the square. I have close to 60 taps sourced from various places, and I don't think I have 2 taps that are close enough to the same size that a machined holder could hold both. Tap holding, precisely and repeatably is a problem I would love to solve. Thanks folks. 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> ------------------------------------------------------------------------------ Transform Data into Opportunity. Accelerate data analysis in your applications with Intel Data Analytics Acceleration Library. Click to learn more. http://pubads.g.doubleclick.net/gampad/clk?id=278785471&iu=/4140 _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
