Okay, saw your other post. If you are bent on pulling the spindle, keep
in mind that you'll have to preload the bearings when you put it back
together. You may also need to replace one or both of those seals. The
outboard seal invariably gets damaged when the threads from the spindle
drag across them while you are beating on the spindle end... And while
you are at it, I'd recommend throwing away the second preload nut. It
will increase the preload after you have set it with the first nut.
Don't know why they made them this way. Take one of them and cross
drill and tap for a 10-32 or such and after getting the preload set,
drop a piece of lead or copper in the hole and tighten a set screw in
the threaded hole. Nut won't back off and you won't damage the threads.
Preload on the machines I'm used to working on is between .002" and
..005". You should find out if the manufacturer has specs on this, some
I've contacted refered me back to the bearing manufacture (who didn't
seem to want to get involved). You can set preload like this:
Reassemble all of the components. Tighten the preload nut unitl the
spindle is just a little loose. Set a dial indicator up so it is
pointing at the nose of the spindle. Tighten the nut and watch the
dial. Just as the dial stops moving is where Zero preload is. If you go
past this point you are setting preload so be careful when you
establish Zero. If you go too far and are not sure where preload is
back off the nut and remove the preload with a mallet. Once you have
established Zero preload, count threads per inch on the outboard end of
the spindle. A pitch of 16 yeilds .0625" of motion per rotation of the
preload nut. Measure the outside diameter of the nut and multiply by
3.14159. Divide this number by 62.5 and that gives you the amount of
circumfrence motion of the nut per .001" of preload. In the case where
your pitch is 16 the amount of motion needed per .001" preload would be
..113". HTH
Doug