On Sunday 07 July 2013 14:33:40 Dave did opine: > On 7/7/2013 1:51 AM, Gene Heskett wrote: > > On Sunday 07 July 2013 01:20:43 Jon Elson did opine: > >> Gene Heskett wrote: > >>> Now I can > >>> > >>> write a peck loop wrapping up the G33.1, that can drive a 10-32 tap > >>> half an inch into a prepared hole, backing out to clear chips, and > >>> do it in perhaps 45 to 60 seconds. Each direction change, at 300 > >>> revs, takes a bit less than 3 seconds for the stop, and accelerate > >>> to the same speed in the other direction. Listening to the z > >>> stepper growl seems to say that it is totally and absolutely > >>> locked. I have killed the motor power in mid cycle, and rolled the > >>> spindle by hand, with the z drive following it perfectly, as I > >>> expected. ;-) > >> > >> I do 4-40 holes with a combined drill-tap in about 12 seconds at 1000 > >> RPM. it takes most of the time doing the drill plunge, then the > >> tapping only takes a > >> couple of seconds. I do 10-32 in pre-drilled holes in about 4 > >> seconds at 660 RPM. Those are single-pass tapping cycles in > >> aluminum. > >> > >> Jon > > > > Chuckle, yes, and I can imagine the cost of the tap to do that. I am > > using what I can get at Tractor Supply, with gullets that wouldn't > > pretend to have enough room to carry the chip load from a hole that > > was likely the nearest fractional 1/64th inch size smaller. But you > > would be amazed at what a 3/32" diameter diamond coated bit, laid in > > the groove, turning slow enough to not ablate the diamond, used to > > deepen the gullets by .005" can do for the performance of such a tap. > > I've also found the usual Ace Hdwe Hansen tap breaks like cast iron > > today, where 50 years ago it was close to the best you could buy. > > > > So today I look for the MIBRO brand, they are not only sharper, but > > can take 2 to 3x the torque a Hansen tap breaks at. Sure, they > > aren't a $30 tap from Henly, but they do a fine job for a 7 dollar > > bill including the right size tap drill. My problem is keeping the > > tap and the drill together after removal from the blisterpack card. > > I should make me some box covers for brass storage plates, with the > > plate having 2 holes drilled in it with each tap drill, and one of > > then tapped for the tap so they are always together. I'll probably > > do that right after I find my missing round tuit. > > > > :) > > > > The best small drill and tap storage ever was the little plastic& > > cardboard sleeve they shipped rifle ammo primers in 50 years ago. I > > still have one of those with all my 6-48, 8-40& 10-32 taps& drills > > (some of those are carbide) stored in it. > > > > Cheers, Gene > > Gene, > > Do you have a Menards near you?
Not that I am aware of. > The tap/drill pairs that they sell > hold up well. I think they are $5.00 for an 8-32 set. > I use them to drill and tap holes in steel control panel backplanes and > they do ok. I chuck the taps in a cordless drill and go to it with a > touch of lube I do that too, but often the workpiece isn't adequately held, so it gets dicey. > I break very few of them. I've used nice spiral point taps but they > last about the same. You are right.. ..Hanson used to be very high > quality. > > Dave > > ------------------------------------------------------------------------ > ------ This SF.net email is sponsored by Windows: > > Build for Windows Store. > > http://p.sf.net/sfu/windows-dev2dev > _______________________________________________ > Emc-developers mailing list > Emc-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-developers Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> is up! My views <http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml> If I have to lay an egg for my country, I'll do it. -- Bob Hope A pen in the hand of this president is far more dangerous than 200 million guns in the hands of law-abiding citizens. ------------------------------------------------------------------------------ This SF.net email is sponsored by Windows: Build for Windows Store. http://p.sf.net/sfu/windows-dev2dev _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
