On Monday 26 October 2009, Glenn Edwards wrote: >Gene, > >Chris is right about the alignment being the place to start- make sure it's >right before you move on. Second, what are the nut and screw materials? >Brass on steel is normal, but if you have something different then keep > that in mind. While dry bearings do have their place, unless you are > generating a lot of dust like Chris I suggest you stay with grease. There > are hundreds of varieties out there, but you should look in the following > places. You may have to run a different grease for summer and winter. > Look for additives that help with lubricity. And get rid of the oils and >combinations you are trying. A good place to start is with Moly wheel >bearing grease for the summer and lithium grease for the winter. And >Machinery Handbook has a good section on lubricants. At the rpm's found on >most machines, manually applying the grease to the screws and bearings >should last several months under hard labor. Good luck. > >-- -- >Glenn > >> One other Q though. My x&y screws are 20 tip acme, and its cooling >> down, even with a heater running the machine is maybe at 55F right >> now, and the Y screw in particular is howling up a storm. Its wet, >> quite wet with a mixture that is part STP and vactra. I've had this >> problem before, and no lube I've tried seems to really be _the_ fix. >> Bar oil, 10w40, 3in1, STP, wd-40 & some spray stuff different from >> wd-40 have all been squirted rather liberally on it to no avail. I >> now have ball bearings in the bearing bosses on the end of the tables, >> and a grease fitting drilled into the bore between them but because of >> the clearance, grease applies very very slowly there, and doesn't seem >> to effect the squeal at all. The bearings are mechanical seals, so >> theoretically I should be able to blow grease right on through them >> given enough time. >> >> Is there a magic panther pi$$ for this application other than money >> for ball screws? > >I guess you have a similar alignment uissue I had recently. Grease did not >solve my problem. To solve it, I loosened all screws that held / fixed the >end bearings, aligned them one by one and fixed them again using loctite. > My mill has roughly 1900x550x250 mm on xyz. So the main thing was on x > naturally. I also had to loosen the "nuts" that position the x axis, > turned them so they would show easy turning and refixed them again using > loctite for the fixing screws. Then I ran a simple code that uses full > extent of all axes for a couple of hours. That wears off the brims that > may have been left from thread production and now I am going at 1300mm/min > on all axes which is good enugh for me. > >I do cut wood mainly. Dust was an issue until I had my dust vent installed >(lots of air sucked in and only occasionally a rather large grain does not >get sucked in). Grease and dust bakes. My finding is, you are probably >better off using dry graphite than grease. I removed all grease and am now >on graphite. > >hth > >chris > Thanks Glenn. I'll take that motor off and check that again in the next day or so.
-- 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) The NRA is offering FREE Associate memberships to anyone who wants them. <https://www.nrahq.org/nrabonus/accept-membership.asp> Jayne: "No offense, Doc, I think it's noble as a grape the way you look after River, but she ain't my sister, and she ain't your crew." --"Serenity" ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
