# Drill Chuck Arbors



## darkzero (Apr 22, 2009)

I've seen arbors that have the groove near the center like the genuine Jacobs arbors. What is the advantage of this? 

I have M2T 6JT arbor. How do I remove the drill chuck? The chuck does not have a through hole. Can I use these although there won't be spindle on the opposite side of the chuck?

I read something here about getting any chips in the tailstock & inserting the arbor heavy damage can be done. Since then I've been keeping the dead center in th tailstock at all times just in case. Am I being over cautious?


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## StrikerDown (Apr 22, 2009)

In an ideal world the taper would make contact all along the surface where the two overlap but the world isn't perfect so by relieving the center you have more sure contact at the far ends of of the shank... Less chance of a high center wobble!


This is just a guess by the way! What say ye?


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## cmacclel (Apr 22, 2009)

You should always keep something in the tailstock taper is a chip will potentially ruin it  If it causes whatever you have in there to spin.

Mac


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## precisionworks (Apr 22, 2009)

The Jacobs wedges are one of the very best ways to separate the parts - a mill vise works well for squeezing them together.

http://www.jacobschuck.com/drill-chuck-install.asp



> getting any chips in the tailstock & inserting the arbor heavy damage can be done


Two ways to really screw up the tailstock taper - chips or grit from leaving the taper open, or a tang that isn't tightly seated. Live centers will seat themselves in use, but a drill chuck tang will not. I use a 5# copper mallet, open the Jacobs chuck jaws all the way, and whack the chuck face two or three times. If you ever spin an arbor, you'll need to buy a finishing reamer & ream until the scoring is gone ... don't ask how I know:mecry:


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## darkzero (Apr 27, 2009)

Thanks for the responses. I ill definitely keep my dead center in there at all times. 

While on the subject, can anyone recommend a decent live center? I don't need something that's high end but then again I don't want something that's cheap junk. 

I've been looking at this Skoda at ENCO. They're on sale right now.


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## precisionworks (Apr 27, 2009)

Skoda (located in the Czech Republic) makes a very nice live center. Another one to consider is the Royal Value Turn:

http://www.use-enco.com/CGI/INSRIT?...MKANO=208&PMKBNO=1904&PMPAGE=50&PARTPG=INLMPI

Although higher in price, Royal is a fine company to deal with when you need repair or rebuilding. I've used their rebuild/exchange program many times, and there isn't a better deal available from any maker:

http://www.royalprod.com/img/category/upload/Page_00 461.pdf

I found out about that program when we were mounting a 72" diameter cylinder on the Niles lathe (84" swing, 1.5 rpm lowest speed). While bringing the tailstock up to the part, and before the faceplate was fully tightened, the part shifted a couple of inches & knocked the front end off the brand new Royal live center, #6MT. Royal said to send it back & they'd fix it, which took just a few weeks & saved a ton of money


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## darkzero (May 8, 2009)

precisionworks said:


> The Jacobs wedges are one of the very best ways to separate the parts - a mill vise works well for squeezing them together.
> 
> http://www.jacobschuck.com/drill-chuck-install.asp


 
I ordered the 6JT wedges since I have a M2T to 6JT arbor. Well the wedges are too wide & does not fit the opposite end of the chuck as pictured in the last pic in link above. Ok, so I figure I would order the next size down & just open up them up to the size I need. So I get the 3JT wedges today & to my surprise they are wider than the 6JT wedges. :thinking:







Am I missing something here? :shrug: The bag for the 3JT clearly says #3 on it & it was sealed. The wedges are stamped #3 on them too. Why would the #3 wedges be wider than the #6 wedges? So now I'm thinking I would need to get the 2JT wedges since my arbor is a M2T but that doesn't make sense to me. I think I'm going to end up with the entire set of wedges before I get this right. :laughing: Now i'm thinking to I order the 1JT wedges & opend them up as needed as planned with the 3JTs. With my luck the 1JT wedges will probably be wider than my chuck! Maybe I should just make some myself.... :sigh:


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## gadget_lover (May 9, 2009)

Take a look at http://www.jacobschuck.com/pdf/Technical-Information.pdf

It show that a 3 is bigger than a 6, and that the next two sizes smaller than a 6 are 33 and 2

I know, the numbers are screwy.

I can't quite figure out the "does not fit the opposite end of the chuck " statement.


Daniel


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## darkzero (May 9, 2009)

gadget_lover said:


> Take a look at http://www.jacobschuck.com/pdf/Technical-Information.pdf
> 
> It show that a 3 is bigger than a 6, and that the next two sizes smaller than a 6 are 33 and 2
> 
> ...


 
Thank you very much for posting that Daniel!

Looking at the chuck on my drill press which is JT33 I assumed JT3 was pretty much similar & went ahead and ordered the JT3 wedges. 

I just read where I posted "does not fit the opposite end of the chuck" & I can't make sense of it either? :laughing: Sorry, sometimes the foreigner comes out of me & I say odd things that don't make sense. Funny thing is I was born here. 

What I meant is the wedges are too wide to fit the lip at the MT2 end of my arbor which is what I'm trying to remove my chuck off of. My chuck does not have the through hole which would have made things a lot easier. I don't feel like drilling it either. Basically what I was hoping to do is like illus. C pictured here: http://www.jacobschuck.com/images/tech-support/tapered-shank-chuck-removal.jpg

Well it looks like I really am going to end up with the full set of wedges. Going off the measurements of my arbor, the wedges that I currently have, & the specs on the datsheet you posted I think the JT2 wedges will work for me. Since shipping costs more than the wedges I'm going to order the JT1 wedges as well on my next order. :ironic: Well if anyone needs buy some wedges you know who to ask. 

Well, another noob learns something new today. Thanks again! :thumbsup:


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## gadget_lover (May 9, 2009)

ALways glad to help.



Daniel


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## precisionworks (May 9, 2009)

The coloring on the wedges indicates that they are case hard. To make the slots wider, a small stone on an air grinder or Dremel tool will work well. Even solid carbide tools don't want to cut through the hard case, which is over 70 Rc.


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## StrikerDown (May 10, 2009)

Are those wedges sold in pairs or singles?

Mght be a nice little project to make!


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## gadget_lover (May 10, 2009)

They are sold in pairs. The idea is to put one on each side of the chuck, wedged between the chuck and the shoulder of the arbor. Then you force the wedges together, creating a clean thrust parallel to the axis of the spindle. 

Using only one wedge will create thrust that is off center.

Daniel


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## StrikerDown (May 10, 2009)

Yea, I figured I needed two, I just couldn't tell from the place I was looking at them if they came 1 or two in the package! 

http://www.use-enco.com/CGI/INPDFF?PMPAGE=483&PARTPG=INLMK3&PMITEM=292-6220

If I look when I am awake I see the Set #!

I just hate getting twice as many as I need!


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