How much run out is acceptable on a drill press?
I’m setting up a new Grizzly 12 speed, 3/4 hp machine floor machine.
The arbor for the chuck has a short taper that accepts the chuck and a long taper that fits into the spindle on the machine.
With the arbor in the machine, the run out at the end of the short taper (about 1″ below the spindle bearing) is 0.001-0.0015″. With the chuck on the arbor, the run out measured on the surface of the chuck, near its lower rim below the key holes is 0.005″. I don’t know if that outer surface is exactly concentric with the jaws and whether that’s a valid place to measure run out. I’ve chucked up many bits, including a centering pin, all of which I am fairly certain of being straight. They all have run out of 0.003-0.005″ at their tips – enough to be plainly visible.
Many attempts to re-seat the chuck result in the same measurements.
Any advice?
Rich
Replies
Did you tighten using all three holes in the chuck with the key? The amount your out could be from not using all three points.
The centering pin should be a valid place to check, the outer body of the chuck not so good for testing.
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Men will never be free until the last king is strangled with the entrails of the last priest.
~ Denis Diderot
Denis,I rotated the bits in the almost-closed jaws to make sure they were centered, but only used one key hole. I'll check again using all 3.Rich
It's important to use all three, let us know how it does.
Don
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Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
Rich, when I check drill press runout I install a 1/2" router bit and measure on the shaft just under the jaws of the chuck.
Life is what happens to you when you're making other plans .
"Life is not a success only journey." Dr. Phil
Jerry,What do you consider acceptable run out?Rich
I like to see 2 to 3 thousands run out on the drill press, router and table saw blades. I have my dad's 60 year old Delta/Milwaukee drill press. I have installed a Albrecht keyless chuck and I measure 0.002" on a chucked bit.
Life is what happens to you when you're making other plans .
"Life is not a success only journey." Dr. Phil
Are you looking for problems? Are you not able to get an acceptable hole? I would be more lenient on a DP at that cost than a $3,000 DP.
I am familiar with the 3 hole chuck tightening issue but I read recnetly the techs at Jacobs don't put much stock in that procedure. One of those old myths it seems.
Bottom line...does the drill press do what you want?? Tech specs are best gotten from the manufacturer and ask how they recommend you check it. Typically one would put a dowel rod in the chuck...I would consider at .005" runout on the rod to be typical on the DP I've checked in that price range over the years to be fine.
Rick,"Are you looking for problems?"Nah. The machine vibrates a bit. All over. It's mainly the pulley assembly on top that's causing it. It's not a pleasing machine to run. So, I've been measuring. But I guess the thing drills well. I've got to do some more testing. I didn't have a break all day, so I couldn't get tech support when they were open. I'll try again tomorrow. They'll probably tell me it's within spec.Rich
Hi RichI had similar problems with an older Taiwanese DP. I found that most of the runout at the bit went away after I thoroughly cleaned and lubed the chuck internals. The vibration went away after I replaced the cheesey belts with Fenner link belts. It turned a nearly useless machine into something pretty decent.David b
"How much run out is acceptable on a drill press?"
5 thou run out on a woodworking drill is immaterial, especially as you are running an ordinary chuck. I may be wrong , but I seem to recall reading Jacobs chucks tolerance specs for different grades of their product and I think they said that 4 thou was average for their medium quality chucks.
However, since the machine is new and the novelty level is no doubt high, any run out can be niggling.
If I were you I would check a few things first, and if you get no improvement just forget about it until you get a chance to acquire a better grade chuck and or taper arbour.
Try the following:
1)Ensure that all taper mating surfaces are clean of grease, clear lacquer or any "deposit" or burrs.Look for shiney areas or spots in the socket-use a good light .
2)Use some engineers blue ink to check the fit of the tapers and if there is discrepancy use extra fine grinding paste to mate them better-but be careful as a little goes a long way when adjusting tapers.
3)Be sure to clean all traces of compound and oil before replacing taper and chuck. Best to install the arbour in the chuck first.
Seems to me that folk get needlessly neurotic about this kind of run out-but pay no attention to whether the arbour is perpendicular to the table.....
Let us know what you do....
All very good advice Philip and should be the first steps in setting up any drill press. However he is only 5 thou. out and in my experience with Taiwan and China chucks this can be from not using all three holes to tighten the chuck. With all due respect to the poster who works on industrial machinery, a genuine Jacobs chuck may not be sensitive to the manner of tightening, indeed I have some French chucks that center no matter what, but many of the Asian import chucks are sensitive to this issue and will work very acceptably if it is observed.
As for the vibration issue the OP will have to decide if the "feel" of the machine is worth the expense of machined pulleys and link belts. As far as useable he is already very close. Amazingly close for the money involved!
Hope things are well with you and yours......
Don
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Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
Don,
No doubt about it- my experience with Taiwanese and Chinese chucks is that they seem to stretch -they feel as though you can always tighten some more and I don't have them on my metal working stuff-even my mill drill el cheapo has a good Jacobs industrial chuck and my Emco mill has an ancient American made Jacobs. But for the price and when used with some care most of them are fine for woodworking drills.
I do prefer to tighten at all three positions because I think the item is evenly gripped-especially if gripping something hardened like a milling cutter (bad practice but it happens).
Nothing to beat an industrial keyless chuck made in Checzkoslovakia though.Philip Marcou
Got a brand name for that Checzk chuck? I'm always looking for good chucks. Them French baby's are pricey.
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Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
Thanks everyone,The arbor surfaces and the chuck bore are in pristine new condition. I carefully cleaned them before assembly.I was so focused on the chuck situation that I had ignored the contribution of the belts and pulleys to the machine vibration. Re-adjusting the motor-idler-arbor pulley relationships (easy one handle control) has gotten the machine to run perfectly smooth and vibration-free. Very nice.I might replace the v-belts with link belts. Doing that on a previous 14" band saw made a world of difference in eliminating vibration.Rich
Consider using cogged type belts. Link belts work best for motors supported by the weight of the motor and standard v belts have a memory issue which causes bounce and loss of power on the bounce. Motors that are fixed in place don't have such issues and cogged type belts are better on smaller diameters and don't have memory issues and they are a lot cheaper. Cogged wedge belts transfer power even better than a regular v belt and a link belt. http://www.mcmaster.com Link belts have their place but if more people understood where they work best and knew about cogged belts they would be raving about cogged belts.
Thanks guys.Rich
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