Hardinge spindle bearing ? (Gunner)

Just wanted to thank Gunner for his excellant step by step essay on
replacing spindle bearings on an old chucker I picked up.I have the
bearings and about to install them but curious about some numbers I see
on the spindle itself (8 and 3) next to the bearing location and the
instructions from the bearing box sais to line up the #'s of maximum
radial eccentricity of the bearings 180 degrees oppisate of the shaft
and housing eccentricity. I am assuming these numbers on the spindle
designate this although Gunner did not mention anything about the
spindle or housing runnout.These numbers are in microns and I figure
that translates to .000003 of an inch, the bearings are marked 2 and
3.Personally I have no concept of how this eccentricity is measured
especially 50 years ago when this spindle was originally ground? This
is the first time I have dealt with such precision bearings and would
like to take my time and learn to do it right the first time. Thanks
for any input on installing or how the hell someone measures to six
decimal points. Jim
Reply to
Jim
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http://65.204.160.42/index.php?id=788ideas?
Reply to
wws
Just line up all the little arrows on the bearings.
Reply to
PrecisionMachinisT
Or the little dots.
I got a pair of Grade 8 bearings the other day that had NO alignment markings. I called the distributor, he checked the shelves..none of them had marks. I told the customer, he needed the machine ASAP...so in they went with the numbers lined up. Ill check on em in about 10 yrs and see how well they are holding up.
Gunner
Reply to
Gunner
Line up the marks on both bearings, and stick em in. The chucker will never know if you are a couple millonths out.
Glad the FAQ was of some help.
Gunner
Reply to
Gunner
no arrows so I just lined up the numbers and everything went together nicely, now all I hear is the belts bouncing. Does anybody have an after market part # for the top belt on a chucker. # on the belt is H615-9625, Good Year 46 but my local bearing shop can't seem to cross reference it .Also I have a cog belt on the motor, is it ok to use cogs on the spindle end. Thanks again. Jim
Reply to
Jim
Belts are hard to find for the Chucker. Bite the bullet and buy em from Hardinge. You will only have to buy em once every 25 yrs or so.
Cog belt on the motor? Or are you talking about the split back on the drive belt? Thats to allow the belt to bend better as it goes through the vari-drive. Less wear. The spindle belt should be flat backed, else you may see some pattern show up in a finish turn. Might see a bit of herringbone with a split backed spindle belt.
Belt bouncing? Set the vari-drive in the middle of its range, then adjust the front elevator bolt until you have approx 1 1/8" movement when you squeeze the motor belt together in the center. The two hanger bolts at the back of the motor plate housing may have to be raised or lowered if you have stretched belts and the front elevator bolt is out of travel. Be sure to check that there is a rubber washer UNDER the motor plate on the flange of the elevator bolt and a similar rubber washer, steel washer over it and a lock nut to hold it in place. If you still have rumbling..take a pry bar and see if the rubber bushings that hold the elevator bolts at the rear are toast. If so, turn down a couple rubber lab stoppers or order them from Hardinge. They are like $10 or so for the pair.
Check your brake cork also. If its badly worn, wrap a single turn of black electricians tape around the cork, reseat it in the brake, and set the energized gap to about 1/16" inch, and put on a couple drops of any oil, even motor oil. Oil it every couple months with a couple drops.
Gunner
If you are going to use that phrase then you should use the full phrase of "Fuck Off and Die and Rot In A Ditch and Get Eaten By Maggots and Pissed On and Shit On By a Dysenteric Elephant (but not necessarily in that order)."
Crash Street Kidd
Reply to
Gunner
My apologies to the group... Mark, could you please send me your latest e-mail address? I've tried sending a couple of notes to your latest address on this subject but no response. I understand if you are overwhelmed with other work.
Best wishes, Mike
Reply to
Mike Hanz
its the same gunner at lightspeed dot net it has been. Perhaps I have my spam filter set too high. Use something like Hardinge etc in the subject line so I can look for it and put you on the friends list.
Gunner
"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences." - Proverbs 22:3
Reply to
Gunner

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