Drill Press Accuracy (Lack Off...).

So, my DP is a Taiwanese Jet (17") that I bought new about 26-27 years ago. I've repowered it, installed a quality chuck,
and done some work to align and balance the pulleys. For most of what I do with it, it's been satisfactory, but if I need to drill a reasonably accurate hole, It almost always wanders off. Now, before you guys tell me there's only so much I can expect from a DP, I know this. I don't expect milling machine accuracy by any means. But I'd like to do better, and before you ask for numbers, I don't have any for you. I've tried everything I can think of. I measure, layout and center punch carefully, raise the table as high as I can manage, make sure everything is locked down, clamp the work to the table or in a vise, use screw machine drills to minimize deflection,
etc.
I just came back from the shop where I put an indicator on the table, extended the spindle to what I figure is a typical drilling position
and push/pulled on the chuck side to side. I got about .025 of play, so I'm thinking bearings could at least be part of my problem.
They aren't noisy or rough, but they are 25+ years old and probably not the best bearings to start with. Ideas?
 
My Duracraft floor drill,(bought in the seventies) at a sidewalk sale. Had a similar problem, when the quill
was extended there was excessive side-play. Bearings were not the problem, the quill hole in the casting was oversize by
a few thousands. Solution to the side-play was to install 4 -5/16 socket head set screws in the casting, pressing against the quill with
brass inserts. Side-play removed. Table rack was locked to main support tube to prevent table movement when raising or lowering.
 

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Good thinking. Mine actually has a screw/locknut arrangement on the side that helps take up the slack.
I still am inclined to think my bearings are sloppy. They probably weren't the best quality bearings to begin
with, and they are 25 years old. I just need to get busy and break down the DP for replacement. :)
 
So, I decided to pull the DP apart today and removed the spindle and quill, and the bearings without any
trouble. Just had to bore a 2" long spacer to drive the bearing off the end of the quill.
But, taking the pulley off the top is another matter. Mikey's writeup recommends using a puller, which I have, but
I hesitate to use too much force to avoid damaging the pulley itself. I heated the pulley with a heat gun to try to
make it easier to remove but that didn't seem to help. Does anyone have any other ideas? Mikey, are you there?

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I'm here. The pulley is just sitting on a taper on top of the drive sleece so once you remove the nut, there is nothing else holding it on aside from that taper. One thing you can try that might work. The drive sleeve sits on a circlip that you can reach from underneath the sleeve, inside the head casting. You can try removing the circlip and put a rag or something to catch it. Then brace the pulley with some wood underneath the pulley so it is well supported, then take a Delrin or aluminum rod and give the drive sleeve a whack from the top. That might shock it loose.
 
Great. I'll have a look for the circlip. Didn't know that was on a taper. I run some Kroil down there as well.
 
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