I was curious about holding power using a worn Torque Rite air actuated power drawbar on a mill with an R8 collet that I suspected was slipping. I checked it by putting a piece in the R8 collet that had a 1/2 inch square pocket that would accept a torque wrench. Holding the brake or putting it in low gear gave me a value which I compared to other machines with the same setup.
On Thu, Nov 10, 2022 at 1:38 PM Matthew Herd <herd.m...@gmail.com> wrote: > I’ve had good luck with Maritool hydraulic chucks in CAT40. Haven’t tried > to push them to the limit yet, but I’ve done about 400 IPM with a 3 flute > 3/8" endmill and it was basically silent. Haven’t tried shrink fit holders. > > > On Nov 10, 2022, at 1:21 PM, Stuart Stevenson <stus...@gmail.com> wrote: > > > > I don't remember seeing anything in the booth about the size of the > holder. > > I did comment to the booth attendant about the need for the 'threaded' > > shank if the holders held so well. She just smiled. > > > > On Thu, Nov 10, 2022 at 8:02 AM Thaddeus Waldner <thadw...@gmail.com> > wrote: > > > >> A key advantage of the shrink-fit toolholder is that the clamping part > is > >> much smaller than anything else. These holders are often specialized > for > >> accessing deep pockets. > >> > >>> On Nov 10, 2022, at 6:31 AM, Stuart Stevenson <stus...@gmail.com> > wrote: > >>> > >>> Gentlemen, > >>> I walked into a booth at IMTS a few cycles ago. This booth was a cutter > >>> manufacturer touting the shrink fit tooling and heat shrink machine > they > >>> manufacture. All the propaganda focused on how the shrink fit process > >> holds > >>> the tool better than any other method. As I was looking at the line of > >>> cutters in the display I saw an end mill with a spiral groove on the > end > >> of > >>> the shank portion. I asked what that was for. I was told this was > >> developed > >>> to prevent the cutter from being pulled out of the adapter during high > >>> speed cutting. It also prevented cutter spin in the adapter. > >>> I have never owned or tried shrink fit tooling. > >>> I have wasted my money on the so-called "hydraulic" collet holders. The > >>> holders' performance was an absolute joke. > >>> The ONLY non spinning/pullout end mill holder(adapter) I have seen is a > >>> mechanical (ie weldon) style. > >>> I will say my high speed experience is limited to a 14,000 rpm 50 taper > >>> spindle but if the cutter manufacturer had to develop a mechanical slot > >> to > >>> prevent spinning/pullout maybe the focus to prevent spinning/pullout > >> should > >>> be mechanical even at the bridgeport level. > >>> Just sayin > >>> HTH > >>> Stuart > >>> > >>> > >>> On Thu, Nov 10, 2022 at 2:34 AM gene heskett <ghesk...@shentel.net> > >> wrote: > >>> > >>>> On 11/10/22 02:48, John Dammeyer wrote: > >>>>> > >>>>>> From: gene heskett [mailto:ghesk...@shentel.net] > >>>>>> It works well John, on the go704. I'd like to come up with a qcth > >> holder > >>>>>> for them on the Sheldon as it has the torque to drive much bigger > taps > >>>>>> but haven't quite figured out how to make such a critter, plus the > >>>>>> sheldon has no gibs to constrain the carriage from being lifted > clear > >> of > >>>>>> the ways when huge gobs of the torque reaction comes into play. I'd > >> need > >>>>>> to hang another 30 lbs on the back end of the crossfeed to contain > >> that > >>>>>> for say a 3" tap. That in any event even though I have the tap that > >> big, > >>>>>> is a g76 job. But at a 3" size, I'd be longer shaping the boring > tool > >>>>>> that doing it, my CBN wheels are quite fine, 2500 grit but fine is > >> also > >>>>>> slow, fragile and expensive. > >>>>> > >>>>> Hi Gene, > >>>>> I'm mostly using the TTS holders and some of my more expensive > tooling > >>>> is still R8 so I'm not converting over completely. > >>>>> > >>>>> I'm thinking that your approach with 4 set screws to hold the tap > might > >>>> work well with TTS holders. A custom holder with a hole for the tap > >> shank > >>>> and 4 set screws keeps the tap from turning. > >>>>> > >>>>> Now we're back to the original question I posed. If this TTS holder > >>>> with a 3/4" shank into the custom R8 holder with say 20 ft-lbs torque > on > >>>> the drawbar won't turn then it's fine for tapping up to the tap size. > >>>> Since the TTS come with at least 1/2" holes it makes for a reasonably > >> large > >>>> tap. Up to 7/8" shank which is once again listed as the limit for > R8. > >>>>> > >>>>> And it makes the tap holders a lot less expensive than using ER20 > >>>> collets which are only good up to a certain size. Purchase a TTS for > >> 1/4" > >>>> shaft, mount in a lathe collet and bore to the size of the target tap. > >>>> Drill the 4 holes and tap them. Now it's a TTS Tap holder. > >>>> > >>>> And I'm having a hard time visualizing that, can you scribble up > >>>> something and put it on your web site? > >>>> > >>>>> If one wanted to modify the spindle it would be possible to put a pin > >>>> hole just outside the diameter of the TTS tool. Then modify the TTS > tap > >>>> holder to have a flange like the pin on your holder that goes into the > >>>> collet. > >>>>> > >>>>> In fact, modify all the TTS holders to have the flange and it's > >> possible > >>>> to prevent all TTS tools from spinning in the R8 holders. Not only > that > >>>> but the M66 command can put the pin in the same place so installing > TTS > >>>> indexed tools becomes trivial. > >>>> > >>>> The word flange is confusing me unless its used to establish a > constant > >>>> length to put in the tool table as TLO. And that would still be > subject > >>>> to error from inconsistent tightening of the drawbar. > >>>> > >>>> My next mechanical thing on the go704 will be stripping a 1/4 > ratcheting > >>>> screwdriver motor out, and rigging it on old 3d printer screws to > >>>> reengage/disengage from the drawbar, It has the torque I think, to > break > >>>> the drawbar or strip its threads in left to hammer the bar for more > than > >>>> 1 or 2 seconds. Then rig M6 to run it for tool changing, possibly from > >>>> mid gcode file. I use the drywall screw driver to do that now but need > >>>> more hands, one to run the driver, one to hold the spindle still, and > >>>> one to catch the tool when it comes free. By my count that's three > >>>> hands. :o) Needs more thought... > >>>>> > >>>>> John > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> _______________________________________________ > >>>>> Emc-users mailing list > >>>>> Emc-users@lists.sourceforge.net > >>>>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>>>> . > >>>> > >>>> 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, 1940) > >>>> If we desire respect for the law, we must first make the law > >> respectable. > >>>> - Louis D. Brandeis > >>>> Genes Web page <http://geneslinuxbox.net:6309/> > >>>> > >>>> > >>>> > >>>> _______________________________________________ > >>>> Emc-users mailing list > >>>> Emc-users@lists.sourceforge.net > >>>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>>> > >>> > >>> > >>> -- > >>> Addressee is the intended audience. > >>> If you are not the addressee then my consent is not given for you to > read > >>> this email furthermore it is my wish you would close this without > saving > >> or > >>> reading, and cease and desist from saving or opening my private > >>> correspondence. > >>> Thank you for honoring my wish. > >>> > >>> _______________________________________________ > >>> Emc-users mailing list > >>> Emc-users@lists.sourceforge.net > >>> https://lists.sourceforge.net/lists/listinfo/emc-users > >> > >> > >> > >> _______________________________________________ > >> Emc-users mailing list > >> Emc-users@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/emc-users > >> > > > > > > -- > > Addressee is the intended audience. > > If you are not the addressee then my consent is not given for you to read > > this email furthermore it is my wish you would close this without saving > or > > reading, and cease and desist from saving or opening my private > > correspondence. > > Thank you for honoring my wish. > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
