On Tuesday 30 October 2012 09:50:06 John Thornton did opine: > Another reason is collet holders are much shorter than a drill chuck and > on Z challenged machines like my BP switching between an end mill holder > an a drill chuck is not always a practical thing... but at $200 for a > set of collets it will be out of the range of many home shop machinists. > I do have a jacobs chuck for my BP but don't use it. > > John > I have similar problems with my little toy mill. The average, I can buy it at Lowes, replacement chuck cannot reliably mount or hold the drills I use which can go as small as #72's. If I ever seriously damage the chinese Horse brand chuck that came with the mill, I'll be out of business for drills under 1/16". And its runout leaves a lot to be desired & getting worse. I have to creep up on starting the hole and give it time to self- center, if it will, depends on the work material. copper plated pcb's are usually ok, TSC's grade of steel rod for a BP nipple gets very very pickity & needs wholesale qty's of the chosen bit size because that dulls them rapidly. And I've not found anyone who will sell me carbide #68's in ten packs w/o a 3 digit price yet. :(
For this sort of work, I seriously need an old 1/4" chuck from a 50 yo electric hand drill, but it still drills holes & I hate to tear up something that actually still works after all this time. :) > On 10/30/2012 7:31 AM, Erik Christiansen wrote: > > On 30.10.12 06:15, John Thornton wrote: > >> I don't use a drill chuck on any of my mills, I've been told ER > >> collets are much better and that is what I use. > > > > Can't disagree a lot, for milling, anyway. IIRC, it was in a Tormach > > document that I read a note similar to this: > > > > Drill Chucks: > > Using a drill chuck to hold a tool used for side cutting is > > dangerous, though educational and often expensive. A Jacobs taper > > is _not_ designed for lateral loads, so vibration and side loads > > generally shake the drill chuck off its mount. As the spinning > > mass dissipates its kinetic energy, the flailing cutting edges > > shred any flesh or other vulnerable material in its path. Drill > > chucks are only to be used with axial forces, i.e. drilling. > > > > It's now one of my MOTD entries, so once in a while my wetware RAM is > > refreshed. > > > > I'd hate to buy a collet for every drill size I might use. Amen on that! Not to mention that for my #2 morse spindle, collets under 1/8" suddenly are made from unobtainium. > > Erik > > ------------------------------------------------------------------------ > ------ Everyone hates slow websites. So do we. > Make your web apps faster with AppDynamics > Download AppDynamics Lite for free today: > http://p.sf.net/sfu/appdyn_sfd2d_oct > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users 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! <doogie> joy/elmo: why can't the same ip be used? was this fire so great that it burned the ip address? ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_sfd2d_oct _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
