Greetings all; I seem to have a saddle that is bell mouthed. Or something.
I can get a new saddle from LMS, about $60. I put the front tapered gib on last evening, parking a mag base .0001 dial on top of the saddle with the finger riding the flat behind the v-way. I had done this the day before to see how much of the brass I could cut off the small end, and had then cut it off at that mark, and about an inch longer on the fat end, then made the screw like R. Kruger did. Drilling and tapping the screw hole was a trick as the clamp is hot roll, and diamond hard in the center. The correct sized tap drill, about 3.44mm's in diameter, went in at paint drying speeds for about .200" and the first inch and a quarter just exploded. Took the remains to my oldest drill doctor & resharpened it. Went back to the docs and set up a G83 to finish it, at about .004 per peck, drowning in cutting oil. Then did the same with the rigid tap g33.1, setting it for a very small advance per peck. Took a while but didn't break the only 4mm tap I had that could go deeper than the thread length as it had a short section of reduced diameter. Entry worn a bit sloppy but works. then milled the screw heads slots nominally .099" wide, 4 of them at .2" intervals .0625" deep, so as to be able to move to the next slot for the screw head as it wore. So I go out to put that on it and useing the dial to see if I could get rid of the carriages twisting on the bed, which makes it climb the v-way and cut a bigger hole moving to the right than when going into the hole toward the left. By several thousandths, But the dial refused to indicate less than a 2 thou diff on a repeat move. So I kept driving the wedge farther. I wound up, without creating a drag the z motor felt, driving the taper around 3/4 inch out of the left end of the clamp. When I quit for the night, it was all the way in and still showing a noisy 2.5 thou of jump. I'll take it apart again today, looking for why, and take .010" off the mating face of the clamp while I have it out. I have not removed the rack strip as its the back guide for tapered gib. And its thick enough the gib rides the smooth side above the teeth of the rack. I get the impression I am cutting thru a coating on the bottom of the bed lip, or something in that category. The old gib plates were worn about a thou bell mouthed on both ends, so I would have to assume they were keeping that underlip fairly clean. In other words, I think the one of you who called it "the little monster" hit it square on the head, and the name has stuck, because its darned sure being one. :) To give some credence to the rubber frame claim I've made many times, the replacement saddle's shipping weight is 3 lbs. And I have seen it bow up or down in the middle from cutting forces! When I am ready to run the Sheldon with a computer, I know exactly where it will come from. That one's drive has room for dozens more configs, and the the electronics box can serve as the starter kit to drive the X. And I have the complete kit I took off the mill to run Z with. Slow, but it will get the job done since the spindle is also slower, and will go plenty slow enough without the noisy back gears once I swap the 3/4 hp single phase 120 volt motor for a 1 hp 3 phase motor on the inverter. With the inverter I have about a 6 to 1 speed range. On that table, the motor seems happy with a 20 hz drive, or with a 120 hz drive, and with its new bearings, maybe 180 hz. Limit, now that I've had one of them apart will likely be fan disintegration although it seemed failry substantial when my bearing puller leaning into it to get a purchase on the old bearings. With a 4 slot pulley setup down below, I ought to be able to spin at any practical speed w/o the backgears. After getting a Z screw, the next biggest cost is tool holders for that Phase II QC tool post, they are 4x the cost of the ones for the little monsters smaller QC post. Ouch! And it only has 3 IIRC, not near enough to be able to setup a usable tooltable. And thats the Sunday afternoon news from a small village in WV. :) I hope everyone is well. 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> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
