I done it. Have an old Craftsman 15" floor DP that has had .008 runout
in the spindle for a couple decades. Just used it for junk drilling, and
very rarely. Decided to fix it quick and dirty, so rigged a dial gauge
to read the chuck body, turned the spindle to max deflection, backed off
the dial, and smacked the chuck with a BFH fairly hard. Recheck; .007.
Hmmm. Smack; .005. Smack; .002. Smack; dead nuts. 'Bout time I did
something with that.
JR
Dweller in the cellar

--
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Home Page: http://www.seanet.com/~jasonrnorth
If you're not the lead dog, the view never changes
Doubt yourself, and the real world will eat you alive
The world doesn't revolve around you, it revolves around me
No skeletons in the closet; just decomposing corpses
--------------------------------------------------------------
Dependence is Vulnerability:
--------------------------------------------------------------
"Open the Pod Bay Doors please, Hal"
"I'm sorry, Dave, I'm afraid I can't do that.."

"JR North" wrote in message
.. .
I done it. Have an old Craftsman 15" floor DP that has had .008 runout in
the spindle for a couple decades. Just used it for junk drilling, and very
rarely. Decided to fix it quick and dirty, so rigged a dial gauge to read
the chuck body, turned the spindle to max deflection, backed off the dial,
and smacked the chuck with a BFH fairly hard. Recheck; .007. Hmmm. Smack;
.005. Smack; .002. Smack; dead nuts. 'Bout time I did something with that.
JR
Dweller in the cellar

Way cool!

Harold

On Feb 5, 7:00 pm, JR North wrote:
I done it. Have an old Craftsman 15" floor DP that has had .008 runout
in the spindle for a couple decades. Just used it for junk drilling, and
very rarely. Decided to fix it quick and dirty, so rigged a dial gauge
to read the chuck body, turned the spindle to max deflection, backed off
the dial, and smacked the chuck with a BFH fairly hard. Recheck; .007.
Hmmm. Smack; .005. Smack; .002. Smack; dead nuts. 'Bout time I did
something with that.
JR
Dweller in the cellar

--
--------------------------------------------------------------
Home Page:http://www.seanet.com/~jasonrnorth
If you're not the lead dog, the view never changes
Doubt yourself, and the real world will eat you alive
The world doesn't revolve around you, it revolves around me
No skeletons in the closet; just decomposing corpses
--------------------------------------------------------------
Dependence is Vulnerability:
--------------------------------------------------------------
"Open the Pod Bay Doors please, Hal"
"I'm sorry, Dave, I'm afraid I can't do that.."

Did you see the hair line cracks in the casting?

Paul

I have an arbor-mounted R8 drill chuck (Rohm keyless, nice chuck) for
my Excello vertical mill. A while ago I came in one day and found
that it was running ~10 thou out, probably because someone
accidentally cranked the vise into the side. I asked a couple of
professional machinists and they told me to simply find the high spot
and use the side of the vise to simply press it back. I tried it and
it worked fine, although I ended up buying a new Jacobs ball-bearing
Super Chuck for $40 and a new arbor. The old arbor, which was quite
dinged-up, went into the scrap bin, while the Rohm keyless got a new
MT2 arbor and was dedicated to lathe use. After measuring the TIR of
the old chuck and arbor separately, I'm pretty sure that the runout
was in the taper connection, and not an actual bending of either of
the parts.

JR,
Reminds me of my first machining job in about 1967. I had one
semester of machine shop, and was working in a shop to support a
family. This particular day, I was drilling the bolt holes in the
flange of a ~10" Brass globe valve. (Apparently the back rake angles
were in semester #2.) Well, the 3/4" drill chaght, and threw that 75#
valve across the shop. The boss was nice enough to let me straighten
the quill, in an "H" press. (Or buy a new one.) The last guy bought
a new table for the DP, after drilling holes in the table.
Dave



On Feb 5, 7:00 pm, JR North wrote:
I done it. Have an old Craftsman 15" floor DP that has had .008 runout
in the spindle for a couple decades. Just used it for junk drilling, and
very rarely. Decided to fix it quick and dirty, so rigged a dial gauge
to read the chuck body, turned the spindle to max deflection, backed off
the dial, and smacked the chuck with a BFH fairly hard. Recheck; .007.
Hmmm. Smack; .005. Smack; .002. Smack; dead nuts. 'Bout time I did
something with that.
JR
Dweller in the cellar

--
--------------------------------------------------------------
Home Page:http://www.seanet.com/~jasonrnorth
If you're not the lead dog, the view never changes
Doubt yourself, and the real world will eat you alive
The world doesn't revolve around you, it revolves around me
No skeletons in the closet; just decomposing corpses
--------------------------------------------------------------
Dependence is Vulnerability:
--------------------------------------------------------------
"Open the Pod Bay Doors please, Hal"
"I'm sorry, Dave, I'm afraid I can't do that.."