Gene, I just wanted to pass along my source for fasteners and they will sell you just one at a reasonable price.
Albany County Fasteners http://www.albanycountyfasteners.com/Default.asp On 7/2/2015 1:04 PM, Gene Heskett wrote: > Greetings all; > > I am now calibrated well enough that I can actually run wood carving > code! And it looks like I could crank up the feed rate a bit, but the > finish obtained will determine that. > > The comment someone made about that BOB being slow, depends on the > polarity of the pulses. Using a common +5 for the opto source, and > treating the BOB as an open collector, I am using 5i25 step and space > timings of 2 u-secs. The ugly slow can be seen on my Hitachi, but the > motors run fine at 45 ipm, which is 35 faster that the little mill can > run. > > Now, if I had those slot opto's & switches, I could begin to bring the > spindle under LCNC control too. > > 3 things of note, z would not go up to the end of the scale on the post, > but I did some disassembly, and the limit is the nut bracket, either > one, OEM or the ball screw version, hitting the top of the slot in the > post. The other is that while those screws are supposedly 16x5's, my > scales do not agree with a 1" range dial indicator. By 1 to 3%. And I > have taken considerable care to make sure the indicator was aligned with > the axis I was checking. Its not skipped steps as I stretched the 5i25 > timeing way out, and the error remains the same but somewhat different > per screw. > > There is a digital DRO on the quill, but I haven't thought to check it > against the dial indicator. > > What has been others experience in this calibration aspect? Can I > believe the dial indicator. Being gear driven, over long ranges, since > a full inch is 10 turns around the dial, my spidey sense says it could > have a cyclic error, but from needle 0 to needle 0, it should be dead on > with the real world. Right? > > 3rd, is the very heavy preload on the spindle bearings as this one was > shipped. Obviously heavy drag when the backgear was in neutral. > > So I took it apart, loosened the tension nut about 5 degrees, padded the > top of the shaft with a 1/2" thick block of alu and gave it a decent > whack to drive the shaft back thru the upper bearing to gain some > clearance. Then drove the nut back to within a degree of its original > position, at which point I was no longer able to feel any play, and the > drag was just starting to increase. Reassembled the whole thing. > > Before I did that, 30 mins at 2300 revs was warming the spindle up, > measured on the lower face of the quill, from 74F in the room to 121F, > 47F rise. Now, an hour gets it to 86F, a 12F rise and much more > tolerable & lots less spindle growth due to heat. > > Anyway, progress, its alive! > > I did have to reboot to regain the motor control once, this thing needs > more memory, 384 megs just doesn't do it. But my son will be here on > the 7th, with another machine with more cpu and memory iron in it, which > should help. No chance in hell of finding another 256 meg pc-133 stick > in these here parts. That would give it 512megs. > > I also think that will help the mouse. As it sits, if the mouse gets > blanked while geany or whatever is running, then when I go back to the > LCNC screen, the pointer is gone, and it often takes half a minute or > more of driving it around before the pointer becomes visible again. > Thats a major PIMA to me. And in the xfce prefs, no sign of any mouse > blanker controls. I wonder, could that be disabled in > the /etc/X11/xorg.conf somehow? > > Not exactly ready for prime time, but it is the middle of the > afternoon. :) > > Cheers, Gene Heskett ------------------------------------------------------------------------------ Don't Limit Your Business. Reach for the Cloud. GigeNET's Cloud Solutions provide you with the tools and support that you need to offload your IT needs and focus on growing your business. Configured For All Businesses. Start Your Cloud Today. https://www.gigenetcloud.com/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
