What type is drill Chuck arbor is best?

Thanks for the input. Now a follow up question. Is there any real difference in stick out between a stub shank and collet or a dedicated R8 drill chuck? Having never done it is seems like there would be no real difference. Of course we don’t know what we don’t know.

As for the discussion about S&D drills, this is interesting. I am very new to these type of drills as well so those are good nuggets of knowledge for me. I like the idea of having slippage at the drill chuck. Again, a novice prospective, to be generous.

If you’re using the same chuck there’s probably nominal difference between using a stub shank with collet and an R8 adapter. Using the collet system would be quicker if you had multiple chucks or other devices with the same shank because you don’t have to pull it all the way out, just loosen.

I was taught that you don’t ever want drills to slip in a chuck, messes up the drill and chuck. If you “want” anything to slip it would be a belt. Paying attention to speeds and feeds, keeping your bits sharp, and stepping up sizes in difficult materials is better than having anything slip.

John
 
Thanks for the input. Now a follow up question. Is there any real difference in stick out between a stub shank and collet or a dedicated R8 drill chuck? Having never done it is seems like there would be no real difference. Of course we don’t know what we don’t know.

As for the discussion about S&D drills, this is interesting. I am very new to these type of drills as well so those are good nuggets of knowledge for me. I like the idea of having slippage at the drill chuck. Again, a novice prospective, to be generous.
No real difference in stick-out, just less clearance required to get the collet and chuck into the spindle. Cranking the knee is good exercise but I still try to avoid very much of it.

Spinning a drill in the chuck is an absolute NO! Machinists take care of their tools. When I worked for Fred, you could be fired for chucking an S&D drill.
 
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Is there any real difference in stick out between a stub shank and collet or a dedicated R8 drill chuck?
Not in the stick out once the chuck is installed, but you get about 2" less clearance required to load the chuck into the spindle with the stub arbor. It might not seem like much, until you are maxed out on your Z axis...
 
The stub arbor argument now makes sense. Again I didn’t know what I didn’t know. As for the drill bit and slippage. I am not so novice that I would invite slippage into the equation. I just have never had any other option other than a drill chuck so it is a new thought process to add. I promise upon all things holy that I will still follow the best practices of correct speed, correct pressure on the bit, clearing chips, the correct use of lubricants and of course drill in multiple sizes to reach final size. Also adding the newest one to me which is spot drilling with the correct spot drill. It is just now that is one more aspect I have to consider. As for the worst case scenario I feel it would be better to sacrifice a drill chuck rather than the spindle of my machine. That was the context in which the original statement was made. Something regarding shearing the locating pin in the R8 spindle vs slipping in a chuck.
 
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Many machinists remove the indexing/locating pin when they get the machine, or soon after. It is a PITA to have to turn the collet till it engages and most seem to think it is unnecessary. Indeed, I removed my pin and have never had an R8 collet slip in the spindle.
 
If I read things correctly, you already have ten chucks? That's jumping in with both feet!

Something to consider is that chucks which don't have integral arbors usually leave a lot to be desired from an accuracy standpoint. For drill press use it's usually not a big deal, but on a mill it can be a significant issue and even on a lathe it can be a consideration. Adding sleeves to arbors is typically going to make things even worse as each time you add a component you're going to increase the error barring a major stroke of luck where they cancel out one another.

I got tired of moving my Jacobs chuck back and forth between lathes so I bought an inexpensive keyless import with an integral arbor. Keyless isn't always ideal for a lathe (or anything really) but I wanted to give one a try. I put it in my drill press and got a touch over .002" runout using a dowel pin of unknown quality. The Jacobs chuck has a removable arbor and I've never gotten accuracy anywhere near that good. My integral arbor R8 Albrecht is a bit better...can't recall, but it was under their max spec which I think is .0015".

For mill use I wouldn't consider anything that isn't an integral arbor going forward...and even the cheap ones seem better than the best chucks with replaceable arbors. Side note, the new Jacobs chucks are imported and get terrible reviews on quality and accuracy.

For some reason I can't get a link to work, but the chuck I bought was from Complete Manufacturer's Equipment in Madison Heights, MI. I've been there and the folks are very nice. They also sell on eBay under "niuniucme" user name and sometimes the price is better on eBay. I'm pretty certain they are actually the importer for a large number of other retailers selling imported tooling based off the comments from the guy I normally deal with there. I was picking up a chuck once and he said "oh, we have 150 of those on hand and ship them out by the pallet to other companies".
 
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A few comments that might be helpful, in general an integrated arbor chuck should have less run out and more rigidity, but it depends on the chuck/manufacturer. The better chucks usually will specify the limits of TIR for a particular product. On my mill I primarily use a LLambrich JK-130-R8 keyless chuck which specs. a maximum TIR of 0.0016" at something like 4" from the chuck, I have checked mine and it is a bit better than that. The other thing that I like about the LLambrich chuck is that the chuck wrench is easy to use and allows sufficiently for reversing, as well as limits pullout from the chuck. As far as stick-out it is pretty much the same as my Jacobs 14N keyed chuck, which has a TIR less than the Llambrich. Getting a higher quality R8 arbor for the chuck as well as clocking the arbor to the chuck, helps to find the minimum TIR position when mounted. I also use a ZLive MT3 integrated keyless chuck in my lathe tailstock, which is quite decent and have not had any issues with it. Shar's also has some integral shank keyless chucks that I have used, very smooth and accurate at a mid price point.

There are a few areas where a keyless chuck is more of a liability in most cases, one is where you need to run the chuck in the reverse direction and they loosen, the other issue is self/over tightening of the chuck. I learned my lesson not to use them on S&D drills, the integrated arbor fractured because of the self tightening. The S&D drills I use have flats on the shank which need line up with drill chuck jaws to prevent rotation, I have not used them directly in a R8 collet. Like others, I removed the R8 guide pin after it got mangled with an R8 arbor. I wouldn't want the R8 collet to rotate from when using oversized drills/high loads. I have had no issues with standard drills up to 1/2" and even some larger S&D up to 1", but these days anything over 1/2" I switch to annular hole cutters.

Fractured/broken arbor on a 1/2" integrated arbor keyless chuck after using it for a S&D drill
Fractered R8 arbor keyless chuck .jpg

Llambrich JK-130-R8 integrated keyless chuck with wrench, I also have one of their Integrated CNC HEXA keyed type chucks with a better TIR spec. but rarely use it.
Llambrich  JK-130-R8.jpg

Arbor TIR is measured first and zeroed, then clock the chuck to the arbor until you have the least amount of TIR and make an alignment mark. The repeatable TIR for this arbor/Jacobs 14N chuck is around 0.0006", which is better than I would normally expect for this type of chuck. I have a generic 3/4" generic keyed chuck and the TIR is ~0.003".
Jacobs 14N chuck clocking for lowest TIR.jpg
 
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