Official Luthiers Forum!

While posting the countersink thread, I found that I did have the recommended zero flute countersink from Woodcraft.

Chucked it up, and it seemed off center. Rotation in the chuck didn't seem to help. Bad countersink? Well I chucked up a different multi fluted one and it ran the same way.

Sooo....I seem to have a problem with runout or something in my Craftsman raial drill press. Anyone have any solutions? Would a new chuck help? I'll try to get some known straight rod to check for runout....
BTW my concern has nothing to do with sanding wings, just showing the press. It's the drilling operations I'm having issues with

TIATerry Stowell38979.9259490741

   You need to use an indicator to see what the deal is. Is it the Chuck or the Shaft or bearings? Also is the surface perpendicular to the drill in all axis?
    More to it than one may think. Also , one last question , are you working a flat or arched surface?
Call me terry and I can help
john

Terry, I agree with john, my drill press table edge is not quite 90 deg. with the chuck. I do my wings with this jig. You make the plywood sled, screws with wingnuts holds the bridge to the sled. by setting the angle of the sled to what angle you want on the bridge, you just flip the sled over to give a mirror cut to the other side. there is an adjustable stope behind the drum that stops the sled exactly where you want giving a nice clean line. The fence on the jig has an adjustment for thickness sanding. I use this for thickness sanding all my small woods. I know it's a sort of "luthiers friend", but I have modified it for mainly doing my bridges. Let me know if you want more pics, I'll post them.

There's a wobble, being perpendicular isn't the problem. If I rotate a bit it SOMETIMES reduces the wobble

Mark, put up some pix. I like what you're doing. What took you so long to get here?

John, I'll give you a shout.Terry Stowell38979.9269328704

Terry here's a few pics of my bridge jigs

Terry,

Using your drill press as a spindle sander is notorious for causing runout,
but it easily fixed. Old woodworking machine repair guru (and I don't use
the term lightly) Bob Vaughan gives the following instructions (lifted from
owwm.org):

Install chuck
Put a 1/2 in x 3 in. steel dowel in the chuck and tighten down jaws.
Put a dial indicator's mag base against the column and the indicators
plunger against the dowel.
Observe runout of dowel.
Mark chuck with felt tipped marker where dowel is out.
Retract indicator's plunger tip.
Pop dowel at that point with a hammer (gently at first).
Put indicator's tip back on dowel and observe if there's a difference.
Engage more violence as needed.

Good Luck!

Dave You beat me to the punch, I was going to describe the same technique. You know that it can be done without a dial indicator. With the drillpress running, lightly touch the dowel with a pencil. The pencil will mark the high point, and that is the side that you whack with a mallet. Lightly at first test again then harder if required.

Al

Terry, if you taper is dirty inside the drill press column connection to the chuck. This can give you runout also! Especially if you apply lateral pressure.

   I don't know how you can remove your chuck on your press, mine's with a drift, but sometimes rust or dirt gets in the column, or the chuck stud and may need cleaning. I usually use scotch-brite and make sure it's impeccably clean before reassembly.

Billy Dean Thomas

_________________
Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

I wanted to add sometimes galling a bit can cause a build up of material on the jaws of the chuck and some chucks are just worse than others.

   Examine the clamping surface of the jaws, there may be something there too!

_________________
Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

     More times than not the run out is actually the jaws in the chuck from wear. Tapping may help for a short time but I do suspect the old chuck. I don't know why but we do tend to abuse things don't we ?
john hall

John is right here, Jaw on any rotating machine are usually the first thing to wear out of concentricty after that the tapered journal may be wobbeled out. If it has been running out for a long time. (hope this is not to be the case).

well, John, time to come visit my shop

I never heard of the "whack-a-dowel" technique, but I'll try it. Now I need to find one....

I need to get this fixed. It's not extreme, but if it can be fixed, I like to keep my stuff tuned up.

Thanks guys.

And while we are on the subject, check the play in your quill too. Turn the crank down to lower the quill about half way. Then grab the chuck and wiggle it fore and aft to see if there is play between the quill and the cast frame of the drill press. Mine had about 0.020" of flop, totally unacceptable if used for routing the saddle slot. I pulled the quill out, drilled into the cast from the front side in two places, think of a triangle of points formed by the two drilled holes and the back side of the quill hole. I then threaded these for 1/4x20 and inserted two nylon tipped setscrews. Put the quill back in and snugged the two nylon tips up against it. No slop at all now. If it gets sloppy later I can just snug up the set screws. Or one could buy a good drill press in the first place...

FWIW,
Alan D.

cool idea. I Like the flexibility (no pun intended) of my radial drill press. It has minor quirks, but I don't want to get rid or it. Yet....