Crap, broke the most important tool in my shop.

Yep its my favorite drill press now, SHe runs real true. Dial indicator with cheap magnetic stand is your friend. Oh yea and a heavy hammer.
CW
 
Chris,

I've got nothing to lose. I'll beat on it for a while. (with proper tools and measuring techniques, of course) Thanks everyone, I'll let you know where I end up.
 
If you tweaked it bad enough to bend the spindle, the bearings are toast anyway, so why not. Wail away. Perhaps the brinelling will help with drill point penetration, you know, like a hammer drill...
 
Lord, just the thought of hammering on a spindle makes my sphincter pucker. But then again, the machine isn't going into production and we're not always trying to hold .001".

*shrug*
 
You're too funny Nathan, I see you used some of the same shop equipment I've worked on, we had a drill press in the County Machine shop that was so bad I'd have to hand drill a larger pilot hole than start the press and capture the walkin' bit in the pilot hole and than try to center the wobblin' piece in a vice or strap clamp and crank it down.

My boss used to say, "...just drill the damn hole, we ain't buildin' a jet engine..." also where I learned the term, "Close enough for goverment work." apparently the goverment has very loose tolerances. :)
 
I don't know Ted, I don't think I'd have a whole lot of use for something like that, except (if you think about it) it is just about the right size and shape to use as a boat anchor.
 
Nathan, I had to make the crap equipment work before they let me use the nice bridgeports or lathes, after my apprenticeship, my first job had me drillin and reamin' holes, (hundreds of 'em a day) I had to learn to compensate for the poor tolerance of the machines. (I hated that job)

When I did finally get a job as a fabricator/millwright, I learned what it was to have good, well maintained equipment to work with, I still cringe when I see a dirty shop
 
I really appreciate everyone's input. I beat the spindle into submission and it is now usable for most tasks. I would never try to make a folder or anything terribly precise, but it is probably as good as when I got it, so that may be why I know what Ted is talking about. I am glad that we have a resident machinist here to keep us honest - thanks Nathan. I'm going to keep my eyes open for a new drill press, or a nice older one with available parts.

I have a question for Nathan or whoever knows. When you measure run out, where do you measure it?
 
You can measure it in two places to get a better understanding of your runout. Chuck a long dowel pin and measure it close to the chuck. Under a thou is great, under .003 is usable. Then measure it out a distance from the chuck, 6" if your pin is long enough. Under a thou is great, under .010 is usable. You're measuring concentricity (how accurately the pin is chucked up centered to the spindle axis), and you're measuring parallelism (how close to parallel is the axis of the dill and the axis of the spindle). It is possible for one to be good and the other to be bad because they're affected by different mechanisms.

You may also notice variation in runout from one revolution to the next. This is your clapped out spindle bearings...
 
Thank you Nathan, great explanation! I have often wondered because, as you have pointed out, at the spindle and away from it will most likely give different readings. I don't need to measure this drill press, I know it's a mess - but this is great information for the future. Take care.

Erik
 
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