Drill Chuck - Seating on Spindle?

Hello, all,
I recently purchased a Jet drill press, and I've been having some
trouble getting the chuck to fully seat properly on the tapered spindle.
The Jet instruction manual said to get everything as clean and devoid
of oil or other lubricant as possible, and I used Brake Kleen spray on
the spindle and the tube that it fits into...however, when I use the
press, the chuck still sometimes "slips" on the spindle when I'm trying
to drill through something.
I have knocked out the spindle-chuck assembly multiple times and
re-cleaned and tried to re-seat it, and still the problem persists.
Can anyone offer any suggestions on how to get this seated properly? I
was considering putting the spindle-chuck assembly into the freezer and
heating the tube on the drill press which the spindle slides up into
with a heat gun or propane torch...is that an acceptable method?
Thanks for any clues.
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If a new taper won't stay put, there is usually a burr or high spot somewhere. Try smearing the tapered end with layout dye or even a Magic Marker, then doing a loose fit with a bit of a twist. The high spot should show up quickly. If you get a full ring of dye, you have a defective taper on one of the parts.
J> Hello, all,
Reply to
If it's a decent fit then shrinking it in place may well make it permanent -- you don't want that.
I've always assembled these with an exceedingly light coating of very light oil -- basically I clean the parts off with oil on a rag, wipe them off firmly, and assemble. The oil limits corrosion, but is in such a thin film that the surface strength is exceeded when you bear down on the drill and that makes enough friction so that everything works.
The only time I've had trouble is when I've been abusing the joint, by putting side loads on it, or making it vibrate under light down-force, or other such foolery. Even there it doesn't slip so much as the morse adapter falls out of the spindle.
You've probably got a fit problem. I know this is inconceivable with newly purchased budget Chinese equipment, but none the less yours may be the rare case where the insanely quality-conscious Chinese labor force has slipped up -- perhaps they were buying parts from Germany, or something.
Do a fit check, per RoyJ.
Reply to
Tim Wescott
I spilled my coffee through my nose... :)
Reply to
T.Alan Kraus
I wondered who bought up all the good Jacobs and Bosch chucks!
Reply to
Rob Fraser
Thanks for the replies. The problem seems to have vanished ... for now. We'll see. I appreciate the suggestions.
Reply to
After verifying the fit, and making sure everything is clean, I was always taught to apply some white chalk to the male taper...
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Burns doesnt it...Dew through mine.....
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Reply to
Gunner Asch
(top posting fixed)
-- snip --
That's interesting. Does anyone here know what that does, and how good an idea it is?
Reply to
Tim Wescott
Chalk -
Softer than either steel. powders finely and fills voids, making contact all around.
Martin Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member.
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Tim Wescott wrote:
Reply to
Martin H. Eastburn
Watch the taper specs- You may have a JT 33 chuck and a B-16 arbor or vise-versa- they are very similar, but will not seat together properly.
Reply to
Jim Insolo
It's in old(1890s) machinist's manuals, three stripes of blackboard chalk on the surface of a taper shank WILL make it stay put. That's assuming no pimples, rings or gouges on the mating surfaces. Been doing it as long as I've been messing with old machinery.
As to why, the old books never addressed that, but one old formulary used rosin as a binder for blackboard chalk.
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