On Tuesday 11 December 2012 11:47:32 andy pugh did opine: > On 11 December 2012 14:49, Steve Stallings <[email protected]> wrote: > > Are the OD of the ball nut and the centerline of the > > > > ball screw concentric? Some castings are offset to > > help with mounting the return tubes. > > I would hope that the outer diameter was concentric, as no other > register is available. > > > Is the OD perfectly round? The bearing that you > > > > referenced is a very thin section and would easily > > distort if the OD of the ball nut was out of round. > > Again, it would be harder to make it oval than round, so one would > rather hope so. > > > How are you going to attach a pulley to rotate the > > > > ball nut? > > Bolted to the flange. > > > You should be aware of lubrication issues. A spinning > > > > nut tends to expel it own lubricant. > > A good point, but one that I will choose to ignore :)
I put zerks into my bearing carriers for the rotating nuts, aligned well enough with a factory hole in the outer race so I can grease mine in the Z drive of my mill, but the spin rate doesn't seem to be high enough to throw it out. I greased them originally, and once since in the 6 or 7 years since I made it. Since I used nooks bronze nuts on 1/2" 10tpi acme bolt for the drive nuts, which can be adjusted to near zero backlash by adjusting the top nut a few degrees, keeping a decently clean coat of grease on the bolt is a larger concern. It is exposed to the elements although not directly dirtied by swarf as its above the head sled casting on that toy. 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! All God's children are not beautiful. Most of God's children are, in fact, barely presentable. -- Fran Lebowitz, "Metropolitan Life" I was taught to respect my elders, but its getting harder and harder to find any... ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
