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View Full Version : drill chuck for tail stock - overall length of MT2 taper question



Mitchell Garnett
09-26-2014, 11:02 AM
Hi,

After a lot of Internet searching without success, I thought I'd see if anyone on the forum has information about this subject. I have a Delta midi-lathe. So far, all the drill chucks I've been able to find have an overall length of the MT2 taper such that the ram has to be extended nearly an inch for the chuck to seat properly. Those of you familiar with this lathe will know that the ram only has about 2" to begin with so I'm losing half the travel.

Does anyone know if shorter tapers are available? Or is the design/specification of the MT2 taper such that the length is set?

Thanks for any advice, info or suggestions.

Mitchell

Shawn Pachlhofer
09-26-2014, 11:19 AM
I have a "good" Jacobs chuck and a cheap one from Harbor Freight.

The good one is longer, and has the same issue in mini-lathes you have.

the cheap one - is shorter, by about 1/2-3/4"

Doug Herzberg
09-26-2014, 11:44 AM
I have the same issue on my GO698. I also have a set of MT drill bits and some centers which don't engage until the quill is out about 5/8".

Thom Sturgill
09-26-2014, 1:18 PM
Same issue with a Jet 1642. I was told you can just saw off the extra length, just make sure there are no burrs.

Kyle Iwamoto
09-26-2014, 2:01 PM
You CAN cut off the "excess" on the end, but cut too much off, and your self eject may no longer work. DAMHIKT. Also, the MT relies on the entire taper for "grip" so....... the longer length MAY be for a reason. The drill chuck has some pretty good forces on it when using larger Forstners.

Steve Paxman
09-26-2014, 3:24 PM
My drill chucks are all cheap ones from Harbor Freight, but I have to have the quill extended quite a bit on the Jet 1642, just like Thom. I guess I haven't worried about it much because I have 4 total inches of travel, so losing 3/4" or so isn't a huge deal to me. I can see where it might be for you, though.

I've never tried it, so I can't vouch for it or take responsibility for it, but I have heard that you can cut the end off, and file down the burrs. Don't go too short - you still need enough friction in there to hold it tightly.

Mike Campbell KS
09-26-2014, 3:49 PM
I had the same problem with all 3 of the drill chucks I have had. The first one that I tried to shorten came out too short:mad: I cut another one about an 1/8" at a time until it fit nice and snug. Just make absolutely sure to file all of the burrs away.

Joe Kaufman
09-26-2014, 4:14 PM
Little Machine Shop has one.

http://www.littlemachineshop.com/products/product_view.php?ProductID=1148&category=7

Mitchell Garnett
09-26-2014, 6:08 PM
Kyle, Steve, Mike - after reading your replies, I decided I'd take the cheap HF chuck and cut off the end. After cutting, I slightly beveled the cut end and ground the end smooth. I managed to get it right on the first cut and it seems to fit snug enough.

Joe - thanks for the link. Despite having successfully shortened my cheap chuck's taper, I will probably buy this one the next time I have $20 to burn.

thanks everyone for their comments.

Mitchell

Peter Fabricius
09-26-2014, 8:17 PM
Hi Mitchell,
Here are the Specs for the MT2. The large end is 17.780mm diameter and the small end is 14.783mm these two diameters are 60mm apart.. It is easy to measures these and determine the working area of your MT2.
If you put a mark on the Taper at the mouth of the tailstock ram, now measure and mark the MT2 for the above diameters and you should be able to see where cutting is possible.
Each Lathe is probably different so cutting in increments is definitely advisable.
Please tell us the distance from the small taper diameter to the end of the cut off you did, this should allow others with your Lathe to begin the cutting.
Hope this helps someone.
Peter F.

Bill Boehme
09-26-2014, 8:29 PM
FWIW, you don't need to buy the whole thing. In most cases, the taper on the drill chuck is a JT6 so all that you need to do is get a JT6 to MT2 arbor that either does not have the tang that is used when installed on a drill press or in the case of some mini lathes it may be necessary to get an arbor with a short MT2 arbor.

Mitchell Garnett
09-26-2014, 8:29 PM
Hi Peter,

Thanks for the specs. I'd found the measurements for the small and large diameter but nothing about the separation/length.

In deciding where to cut the one I modified, I used a "mandrel saver" MT2 as a guide. I didn't think of actually measuring it (duh) so I just held the two together and made a mark at what looked like the right place. In just checking, the mandrel-saver is 60mm so it matches the spec. My mark was off and I cut the one I modified a little short - it's 55mm but seems to work.

Knowing that 60mm works perfectly because of the mandrel-saver, I'd suggest to anyone wanting to do the same thing I did to carefully measure off 60mm before making the cut.

cheers,

Mitchell

Stan Smith
09-30-2014, 2:05 PM
I have a jet midi (1221vs) with the same problem. I bought a keyless chuck from PSI. The MT on it is shorter than my keyed chuck. I just noticed this because I'm working on a project where I have to have the drill chuck in the headstock to hold a 1/4" screw. I couldn't even get the keyed chuck to go all the way in the headstock. The keyless chuck works okay though. The keyless chuck does wobble some so I just ordered the South Bend Lathe SB1375 1/2-Inch by JT33 Keyless Chuck . Wish I could have afforded an Albrecht. There is a tang on my keyed chuck mt but I'm not cutting mine off. Yes, it is a pain to have to keep moving the tail stock even for pen blank drilling using the PSI pen blank chuck (better results for me than using the drilll press). Glad cutting your HF MT worked out for you.

Dave Cullen
09-30-2014, 2:47 PM
The tailstock on my Oliver lathe is just the opposite - most MT arbors aren't long enough to eject. Only the fancy ones with a tang are long enough. I have to knock my chuck and live center out with a block of wood and a mallet.

Mike Wagner
09-30-2014, 3:36 PM
I also just shortened mine like Thom and all is good now.

Mike

Steve Peterson
09-30-2014, 7:01 PM
You CAN cut off the "excess" on the end, but cut too much off, and your self eject may no longer work. DAMHIKT.

I had the opposite of Thom's problem. One of my MT2 tapers was too short for the self eject function on my lathe. Luckily it had a tap for a drawbar, so I stuck a bolt in the hole and all is good. I think it was a 1/4-20 thread.

Steve

Stan Smith
10-02-2014, 4:47 PM
Little Machine Shop has one.

http://www.littlemachineshop.com/products/product_view.php?ProductID=1148&category=7

Hi Joe thanks for that url. The have a list of lathes that are compatible with their chuck. I see that Jet is not listed and that's what I have. Is anyone using this drill chuck on something larger than a mini?

Stan Smith
10-02-2014, 4:52 PM
Hi Peter,

Thanks for the specs. I'd found the measurements for the small and large diameter but nothing about the separation/length.

In deciding where to cut the one I modified, I used a "mandrel saver" MT2 as a guide. I didn't think of actually measuring it (duh) so I just held the two together and made a mark at what looked like the right place. In just checking, the mandrel-saver is 60mm so it matches the spec. My mark was off and I cut the one I modified a little short - it's 55mm but seems to work.

Knowing that 60mm works perfectly because of the mandrel-saver, I'd suggest to anyone wanting to do the same thing I did to carefully measure off 60mm before making the cut.

cheers,

Mitchell

Thanks, Mitchell, that's good info. I have a mandrel saver also so I'll use it to mark with. Guess I'll cut mine with a sawzall and file the edges.

Update: I have a keyed chuck w/#2MT that I got from CUSA years ago. I cut it to the mandrel saver length with my sawzall and filed off the edges. I gained over an inch of travel. I just bought a South Bend keyless chuck. I had to buy their proprietary #2 MT add on. The MT came with a tang even though it's advertised for lathe use. I decided to cut the tang off. I used the grinder ro get rid of the excess. I gained an inch just by cutting off the tang. Again, I'm glad that Mitchell started this thread and the good suggestions that came with it. Thanks everyone!