Drill Chuck Quality

I'd like to get a new drill chuck with 1/2" capacity. My main concern is that it hold the tool concentric to its axis. It will not be used in a manufacturing environment. I currently have a Jacobs #34, but the nose is damged and it has a bit of runout. Do the ball bearing chucks like a Jacobs 14N hold more accurately, or are the simply more durable than a plain bearing type? Suggestions for an accurate, but affordable chuck of this size?
Greg

...accurate, but affordable..." are not mutually exclusive attributes but they do have an inverse relationship. Ball bearing chucks are nice because they run so freely. Problem is they're bulky.

Get either and so long as they bear the Jacobs or another reputable brand name you will get a good long lasting chuck. New out of the box you can expect 0.003" max eccentricity for a basic Jacobe taper mount chuck.

If real concentricity is your concern maybe you should set some limit of acceptability. Higher end Jacob precision and the Albrecht precision keyless chucks are about double or triple the price for about half the concentricity error compared to a good plain drill chuck. A new drill chuck that will be dropped, pounded on, have shanks spun in the jaws, etc will not hold its accuracy long.

I use a 30 year old #33 Jacobs regularly on my turret mill. It runs about 0.003" of true concentricity and it gives me accurate hole locations and a reliable grip on whatever I put in it. It doesn't get babied but I do take care of it and avoid abusing it.

I also have an Albrecht keyless chuck I use from time to time. I paid a fortune for it when I was young and impressed with such things but it doesn't really justify its cost.

If you want concentric drill holding get a DA collet and closer set for your spindle. It's more money yet but they typically run concentric within 0.001".

I would be very leary of buying any new chuck with a Jacobs name on it. From my experience with 3 different chucks built in last 2 years there is no such thing as quality control at Jacobs anymore, except on their taper shanks.

The drill chucks had rough working, horrible runout, poorly ground jaws. These were not low end chucks. Unfortunately I am not the only one to have this experience. Last year another poster shared his experience with a chuck bebuild kit where the parts were poorly machined.

I would buy a Rohm or a made in Taiwan SPI chuck long before I tried another Jacobs.

Michael

Forrest,
Thank you for your reply. I am aware that you get what you pay for. I guess I am just looking for a real world viewpoint of what accuracy is gained with the additional cost. You have provided that. I would be happy with 2-3 thou runout. I am getting 8-12 right now. I have an ER25 collet chuck if need more precision, though not a complete set of collets. Maybe that is where I should invest my money.

Michael, Thanks for sharing your experience.
Greg

I inherited a couple of keyless Jacobs JKP-130 chucks with some cnc tooling. They were worn and I finally stripped one of them out drilling a hole in Handle jog mode @ .01" My Bad

Anyways, I was debating replacing them, as I know a nice chuck can have a pretty short life on a CNC....so I gambled and got a couple of equivalent capacity 'cnc' chucks from Shars, being fully prepared to return them if they were crap. I installed them and was pleasantly surprised that they were not all that bad runout wise, for $50.

When I use one of these drill chucks, I know that I am simply making do with a 'good enough' setup for a quick job. I will use collets when the job calls for accuracy and positive drive of the tool (like for a tap or reamer).

I've pretty much given up on keyed chucks, as I find they don't hold much better than a good keyless, unless running in reverse for some good reason. I tried a couple of Jacobs keyed chucks, 0-1/4 capacity, hoping to hold really small drills with them, but the chucks were crap, the smallest drill they would hold was near .020, and the jaws seemed plenty loose, which made installing the small drills very difficult and resultant concentricity of the drill was poor. These were $100 chucks, and I replaced them with a $20 Shars keyless cnc chuck, which does actually close up on a small diameter drill properly.

If $ is tight, I agree with Michael about the Rohm chucks, good quality for a pretty good price, and www.use-enco.com often has them on sale.

Regarding Jacobs chucks, it would be a real shame if its true that their quality has fallen off. Their cheap chucks have been so-so for a while, but their "Ball Bearing Super Chuck" was on my short list of things still made in America that were both made really well and worked really well.

What I like about the Super chucks is that they have extremely smooth clamping action and for smaller to medium size drills they clamp so smoothly that you can tighten by hand like a keyless chuck. I only use the key for larger drill sizes and heavy drilling.

If you want really nice chuck I'd still give a Jacobs Super a try (also available sometimes on sale from Enco) and if it doesn't have acceptable runout, send it back and get a Rohm.

Any chuck worth half a poop should give you 2 to 3 thou of runout or better.

Paul T.

I have bought two of the Chinese ball bearing chucks and found them to be very accurate. I also have a Jacobs ball bearing 3/4 chuck and two Albrecht keyless chucks. I use the Chinese chuck on a morse taper in the lathe. I like the ball bearing chucks for smoothness and the ease of tightning.

A year or two ago, I bought a new Chinese 1/4" drill chuck on eBay for $9.95 + s/h. The box said "Golden Goose" brand, but the mark stamped in the chuck is a picture of a pelican's head. The chuck looks exactly like a Jacobs key-type "Super Chuck." The exterior finish is beautiful. I do not know if it has ball bearings in it, and I am not going to take it apart to see.

I put the chuck on a $115.00 Levin D (10 mm collet) 1A JT chuck arbor and mounted it in the headstock of my Levin instrument lathe. With a 1/8" dowel pin in the chuck, I saw less than .0001" TIR on an Interapid test indicator. That is as good as or better than any Albrecht or Rohm chuck I ever tested. This Chinese chuck is now the one I use in the collet-holding tailstock of my Levin lathe.

I have a theory that Jacobs is making chucks on worn-out machines. The newest Supreme brand chucks I have (NOS) are kind of sloppy, like they were made on worn-out machines shortly before they went out of business. A second part of my theory is that my Chinese chuck was made on fairly new machines in a quality-conscious factory.

I am willing to pay a premium for an American product if it is good. But, if the best products are either Chinese or German, and the Chinese costs a tiny fraction of the German price, I will buy the Chinese.

Larry

I've purchased Jacobs Super Chucks in both 14N & 18N with the last couple of years. Both have tremendous grip with minimal runout, about .003 TIR. Good enough for the girls I date

My "best" Jacobs is a Hi-Torque Hi-Precision Keyless. Paid $100 for it, new in box on eBay. Shows TIR at .0009, which is as good as most any Albrecht I've ever used. http://www.jacobschuck.com/product_details.asp?pid=37

The maximum grip on the 14N & on the Keyless seem similar. The 14N is used in the lathe tailstock, so the spindle can be reversed when power tapping. The Keyless stays on the mill & has enough grip for small hole tapping, up to 1/2 NC.

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Barry Milton

I kinda went nuts a while back on drill chucks. But I had gotten REALLY tired of spot drill, small drill, big drill, ream, repeat, repeat, repeat....

I looked and looked over a few months and couldn’t find what I thought was a decent deal on a used “as new” chuck for my mill and also wanted some good chucks for lathe and press. Finally bought the Rohm 1/2 from Enco’s sale catalog and mounted it on an R8. Wonderful chuck in every way and very happy, but still wanted something for larger and smaller shanks. Then I found an 18N “never mounted and as new other than shelf storage induced patina”. Got it for $75 and it turned out to be perfect needing only a little love with a Scotch-Brite pad. Figured that was good enough till I could find some smoking deals. Next thing I know, cheap chucks are everywhere I turn. Almost so bad I can’t go to a public restroom without finding a Albrecht in the trash can. I’ve now got something like 4 near perfect Albrecht 1/2 chucks (2 on 1” shanks for my turret, 1 with MT2 in my press, and one MT3 for my lathe), and 3 more 3/8” Albrecht chucks to go through some day (one needs cleaning but otherwise good, one perfect shell with spun jaws, and a rusty shell with perfect jaws for a donor), 2 more 1/4" Albrechts (one on R8, the other not mounted) and even a 1/8” Albrecht currently unmounted. I think I’ve got less than $80 in all of them. Not to mention the 2 14Ns (1 old straight shell on MT2, and one bulb shell on 3/4 straight) and 2 more 18Ns (one has found life as a dedicated spindle mounted chuck on my ongoing grinder project, used for quick mounting various arbors for flap disks and the like). And as suggested, these SuperChucks can run reversed.

Like I said, it got out of hand, but I couldn’t see passing given the prices I was finding. Once I get them all fixed/restored and mounted on appropriate arbors, I’ll be set for quick changes between chucks with all sorts of mounted bits including a “sensitive” mount on the 1/8” Albrecht chuck.

So what’s my point? Mainly that the Rohm 1/2 chuck for ~$55 in the Enco catalog is hard to beat for a quick fix. But used is out there for a good price if you can wait. And most of my current crop of chucks have VERY little runout with the exception of a couple with spun jaws (that were bought for scrap price, so what the heck).