Lets talk runnout
#1
Hey guys id like to know what you guys get AND deem acceptable for drill chuck runnout ?

The mill I have is a PM932 . The two drill chucks that I was dialing in were both a Jacobs super duty ball bearing and an Albriech (sp) key less chuck . I did try many other chucks and collets to see if my observations repeated and or got better worse.
First id like to note that I did many runout checks and indication fix and checked everything soup to nutz. 1st inside diam than a R8 collet it self with drill rod if I can rem .001-.0025 is what the mill produced so thats what we have to start with.

this is still bothering me and I didn't post bc been tied up with other things .. did some runout checks a few weeks ago wanted to hear from you guys . Spent some time observing why .0025-.004 TIR was what I was getting and upon mounting and re mounting chuck their was so much variance ?

After several adjustments re cleaning fixin and even tapping drill chucks I was able to get TIR within . .002 ( this check was approx 1-3” down in z from surface of jaws). .. Now id say however if ya took out chuck and re installed back it went to .0025-.004 TIR AGAIN to me .0025 may have to be acceptable for a drill chuck but not any greater what is your thoughts on this ?? still don't make sense that's like .002 too much

JMHO I never though of checking my runnout on a BP every time I used good quality stuff it never dawed on me drill wasn't running true unless it was obvious
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#2
What's the run-out on the spindle while indicating on the R8 taper surface? That's your baseline. Drill chucks are not known to have low values of run-out, even the good ones.  Smiley-gen163

Ed
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#3
One of the first things that spring to my mind when people ask about runout is: "are you cleaning your spindle taper each & ever time?"

There's even a wickedly expensive tool for it:

http://www.use-enco.com/1/1/82076-spindl...tools.html

Next thing that comes up is "do you have a chip impacted into the surface of the spindle taper?"

Every once in a while I will crank the table down and  the quill up, and get a bright flashlight and inspect the spindle taper.  Any lone shiny spots are a chip which has been jammed into and crushed flat in the taper.  I have a little tiny file which I've ground and honed like a scraper specifically to remove any pimples like this from internal tapers.

If you really wanted to go whole hog, you could use some transfer blue AKA prussian blue to determine if you have high spots in the taper socket.  Even a thick coat of Sharpie from a new marker will do the job.
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#4
we are talkin bran new machine /w ... clean taper surface . Ed I kindas fig that when I put the good drill chucks in and yes I think I checked that to be between .0002- .0005
btw
.I have a habit of cleaning collets every time I take em esp if they get smooched ...also most times when installing I have a habit of cleaning the taper at lest with my finger before installing collet .
so what we are saying here is to expect that much ?? something don't add up .. never noticed that much at work.. hmmm ?
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#5
now what id like to know and get someone to concur is their is a good possibility in what I have observed as far as up to .0035 runout with a good quality chuck lest say 1-2 " from spindle can be from removing taper pin ?

or that should't mean squat Bc i do get good readings with lets say 2-4" down from collet face when using collet instead of drill chuck ?
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#6
Kenny,

We need more information. Exactly how are you measuring the run-out? You say you're measuring some distance from the chuck jaws or collet so we can assume you're chucking something in the drill chuck or collet and measuring run-out by indicating on the unknown object. What are you chucking in the drill chuck or collet and taking the measurement off of?

What taper pin are you referring to? Too much cryptic information here to give you a worthwhile opinion. Chin

Ed
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#7
Pictures would be extremely helpful also...
Hunting American dentists since 2015.
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#8
Also, what size range are these chucks and are they the "genuine article" made in USA (Jacobs) and Germany (Albrecht) chucks or the cheap knock-offs? Have you mounted the chucks on quality arbors or "import" quality ones?

Lastly, don't overthink this. If the drills being used were high performance solid carbide you need 0.0002" runout. With HSS jobber length drills, anything under .005" or so should be fine.
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#9
(11-26-2015, 11:01 AM)PixMan Wrote: Also, what size range are these chucks and are they the "genuine article" made in USA (Jacobs) and Germany (Albrecht) chucks or the cheap knock-offs? Have you mounted the chucks on quality arbors or "import" quality ones?

Lastly, don't overthink this. If the drills being used were high performance solid carbide you need 0.0002" runout. With HSS jobber length drills, anything under .005" or so should be fine.

Those are all good considerations. I struggled to find a drill chuck that satisfied me. I bought this Llambrich with a built in R8 arbor because they promise less than .0006" run out. Even after I stupidly wrecked the first set of jaws and installed a replacement set it still meets their specs. I checked it with a piece of 3/8" drill rod in the chuck.

[Image: 20151121_093158_zpsodwesmow.jpg]

[Image: 20151121_093134_zpsas1ckcp2.jpg]

https://www.youtube.com/watch?v=ddEBrLhY...e=youtu.be
johnncyc14, proud to be a member of MetalworkingFun Forum since Nov 2013.
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#10
(11-26-2015, 12:36 PM)johnnyc14 Wrote: ... I bought this Llambrich with a built in R8 arbor because they promise less than .0006" run out...

I also have Llambrich drill chucks and I've been very please with them for the money.

Ed
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