Measuring TIR, which measurement do I believe?

You should allow 1/64th inch for the reamer on small hole. Larger you can allow 1/32"
 
Yes, I am saying to agressivly feed the reamer, it forces the reamer to center itself in the hole, instead of wobbling around in it.
 
Good to know!!!
 
Remeasured slop in drill press. If I push the chuck near the spindle, I can get 0.010" movement from side to side. (Using my Federal 0.0001/div. One full rotation of the dial!) Not good for metal work. Makes me feel better, I wasn't imagining the "fuzzy drill". When I measured only 0.0012" TIR by gently rotating the bearing, I thought I could live/suffer with it. At 0.010" run out (static) I need a better solution. For me, this is justification to buy a mill. Yeah, I know, some folks have to learn the hard way...
 
It's a drill press, nothing more. It is perfectly fine for its intended purpose. An oversize hole is the fault of an unequal grind on the drill. Once the point is established, the drill will follow it regardless of spindle runout. The looseness of the spindle just means that it will follow the drill.

Not that I'm trying to discourage you from buying a mill.
 
MrWhoopee said:
It's a drill press, nothing more. It is perfectly fine for its intended purpose. An oversize hole is the fault of an unequal grind on the drill. Once the point is established, the drill will follow it regardless of spindle runout. The looseness of the spindle just means that it will follow the drill.

Not that I'm trying to discourage you from buying a mill.
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Is it possible to inspect drills ahead of time for this defect? What does the defect look like?

No, you haven't deterred me at all. Have one coming my way soon. I'll still need to be able to drill decent holes, so how does one 'inspect the drill bits'? Or do you spend the day drilling holes with all one's bits and measuring them with gage pins?
 
Unequal cutting edge length (point off center) is the culprit. A drill point gage is the tool, though it's only as good as your eyes.

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The ultimate test is drilling a test piece and measuring. A drill will always cut on size except when you need it to. Just like a drill press, twist drills are not a precision cutting tool. That's why we bore and ream.
 
benmychree said:
nother thing is to not baby the feed of the reamer, if you do not agressively feed it, it may cut oversize.
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Good to know, I have watched youtubers reaming very slowly (slow feed)
 
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