JT #2-1/2 means exactly that!

I finally removed the chuck from the spindle on my circa 1973 AMT 1/2" bench
drill press -- the one that has been the subject of several threads
including one that concluded that I was absolutely crazy for believing a
nameplate that said it has a JT#2-1/2 spindle.
Well, here are the measurements -- along with specifications I've gotten
from the web
JT# Large Dia Small Dia Length
#2 .5590" .4876" .8750"
#2short .5488" .4876" .7500"
#2-1/2 .677" .625" 1.055"
Reply to
Norm Dresner
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Perhaps you're over reacting.
It would be infinately more surprising for a chuck to have a Morse Taper, than to have a JT 2-1/2.
As far as Morse Tapers are concerned, the chuck was attached directly to the spindle, and not an arbour (which sits in the spindle)? We went over this before, but you didn't mention your findings in this thread. Chuck --> arbour --> spindle = Good news. Chuck --> spindle (unlikely) = bad news.
Regards,
Robin
Reply to
Robin S.
Nobody thought you were crazy. The reaction you posted to the first question, though...
Given that there are milling machines out there (new, not high end though) that would be hard pressed to keep to the runouts you are reporting, most of us would not bother, methinks.
Did you remove the arbor from the drill press? If it IS an MT2 arbor, as the tag said, then ...they are not too expensive to consider just buying a chuck and arbor that match. The arbor would run $20 and the chuck the better part of $200 for new top of the line stuff at retail (estimating).
Cheers Trevor Jones
Reply to
Trevor Jones
| Did you remove the arbor from the drill press? If it IS an MT2 arbor, | as the tag said, then ...they are not too expensive to consider just | buying a chuck and arbor that match. The arbor would run $20 and the | chuck the better part of $200 for new top of the line stuff at retail | (estimating). | | Cheers | Trevor Jones
Given that the manufacturer when they designed the tool in the late 60's (I bought it around 1973) used a now totally non-standard JT#2-1/2 taper, what chance do you think there would be that the spindle/arbor would be replaceable with a modern variety?
{NOTE: The AMT "Instruction Manual" parts diagram calls it a "spindle" which is where I'm getting my terminology from}
Norm
Reply to
Norm Dresner
FWIW I am going to call the rotating part of the drill press the spindle. The adaptor between the spindle and the chuck is the arbor, just so you are clear on what I am saying.
Have you removed the chuck arbor from the spindle of the drill press? That is the area that you will find a Morse taper, probably the MT2 that you mentioned in another post, as referred to in the instructions manual.
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shows that there are no less than 6 different Jacobs Taper arbors available from Jacobs themseves in morse taper 2 size. There are several choices for threaded chuchs as well.
There is a chance that the makers built it with a solid shaft with just a male end on it. That was done on some very inexpensive machines, and is not a positive thing. If you really felt it worth the time and money, the DP could be disassembled, and the spindle reground to an available size, like JT2.
Most common method for removing a morse taper arbor from a DP is to extend the drill spindle as far down as it will go and there is usually a slot in the side of it. By turning the spindle you should find a position where you can see the removal tang of the morse arbor. A wedge is driven in through the gap to pop the morse arbor out of the spindle. These can be bought, but most just make them as they wear them out. They are about 8 degrees taper, rounded on one edge to mate with the edge of the removal slot, and flat along the other.
formatting link
has what you need to know.
Cheers Trevor Jones
Reply to
Trevor Jones
Actually, walker-turner did make a number of their fairly high quality machines with the spindles equipped with a JT33 male thread on the end. Those in particular do work pretty well.
Reply to
jim rozen
I'd guess that they would have worked very well indeed. In practical terms, if one were designing for accuracy, then it does make sense. If the design is to be flexible, the socket makes more sense to me.
Then, the Walker Turners were not an inexpensive machine, either. One would expect them to work well.
Cheers Trevor Jones
Reply to
Trevor Jones
| FWIW I am going to call the rotating part of the drill press the | spindle. The adaptor between the spindle and the chuck is the arbor, | just so you are clear on what I am saying. |
I have the exploded parts diagram in the instruction manual. There is exactly one piece which runs down from the pulley to house the chuck. It is a single piece of metal that the manufacturer calls the "spindle". There is no separate arbor. If you doubt me, I'd be glad to scan the diagram and e-mail it to you.
Norm
Reply to
Norm Dresner
Well, amigo, it looks like you are stuck with what you got, unless you are willing to have at the spindle for putting a new taper on it.
If there is enough meat to it to put a Morse socket into it, that would be the way to go, otherwise grinding the taper to the next nearest Jacobs taper looks to be about the only option besides a new drill press.
If you want to, scan the diagram and put it up in the dropbox at
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where it can be accessed by all interested parties. The instructions for using the dropbox are at the link "using he dropbox" near the top of the page. The upside of that is that it may come useful to someone down the road.
Cheers Trevor Jones
Reply to
Trevor Jones
| >
| > | FWIW I am going to call the rotating part of the drill press the | > | spindle. The adaptor between the spindle and the chuck is the arbor, | > | just so you are clear on what I am saying. | > | | > | > I have the exploded parts diagram in the instruction manual. There is | > exactly one piece which runs down from the pulley to house the chuck. It is | > a single piece of metal that the manufacturer calls the "spindle". There is | > no separate arbor. If you doubt me, I'd be glad to scan the diagram and | > e-mail it to you. | > | > Norm | | Well, amigo, it looks like you are stuck with what you got, unless you | are willing to have at the spindle for putting a new taper on it. | | If there is enough meat to it to put a Morse socket into it, that would | be the way to go, otherwise grinding the taper to the next nearest | Jacobs taper looks to be about the only option besides a new drill | press. | | If you want to, scan the diagram and put it up in the dropbox at |
formatting link
where it can be accessed by all interested parties. | The instructions for using the dropbox are at the link "using he | dropbox" near the top of the page. The upside of that is that it may | come useful to someone down the road. | | Cheers | Trevor Jones
I'm scanning it right now and I'll drop it in as a 3-page .PDF file for the whole manual.
Norm
Reply to
Norm Dresner
|| >
|| > | FWIW I am going to call the rotating part of the drill press the || > | spindle. The adaptor between the spindle and the chuck is the arbor, || > | just so you are clear on what I am saying. || > | || > || > I have the exploded parts diagram in the instruction manual. There is || > exactly one piece which runs down from the pulley to house the chuck. | It is || > a single piece of metal that the manufacturer calls the "spindle". | There is || > no separate arbor. If you doubt me, I'd be glad to scan the diagram and || > e-mail it to you. || > || > Norm || || Well, amigo, it looks like you are stuck with what you got, unless you || are willing to have at the spindle for putting a new taper on it. || || If there is enough meat to it to put a Morse socket into it, that would || be the way to go, otherwise grinding the taper to the next nearest || Jacobs taper looks to be about the only option besides a new drill || press. || || If you want to, scan the diagram and put it up in the dropbox at ||
formatting link
where it can be accessed by all interested parties. || The instructions for using the dropbox are at the link "using he || dropbox" near the top of the page. The upside of that is that it may || come useful to someone down the road. || || Cheers || Trevor Jones | | I'm scanning it right now and I'll drop it in as a 3-page .PDF file for the | whole manual. | | Norm |
Done. The manual is there under the name AMT 4030 Drill Press.
Norm
Reply to
Norm Dresner
We shoulda got that done right in the beginning. Sure would have saved some back and forth.
Nice size scan, by the way, clear enough to read and still fast to get on cruddy dialup.
I wonder if that really is a section of a morse taper that they used on the spindle. Doesn't much matter, as it seems unlikely that there are any chucks available to fit it as is.
As I said before, the amount of runout you say is present is an awful lot less than I would expect to find on a small drill press, and I doubt I would have been doing anything about it without some compelling reason, like a munged up chuck.
Got a lathe and a toolpost grinder? Know anyone that has a tool and cutter grinder or cylindrical grinder?
To the makers credit, they built a nut in to remove the chuck with. Too bad they could not see fit to use a standard size chuck mount.
Cheers Trevor Jones
Reply to
Trevor Jones
Very intresting that they callit a Morse taper in the instalation instructions. ?????? ...lew...
Reply to
Lew Hartswick
| > | I'm scanning it right now and I'll drop it in as a 3-page .PDF file for | > the | > | whole manual. | > | | > | Norm | > | | > | > Done. The manual is there under the name AMT 4030 Drill Press. | > | > Norm | > | Very intresting that they callit a Morse taper in the instalation | instructions. ?????? | ...lew...
Yeah. We've commented on that before since it was the source of some confusion. But the nameplate on the DP I have clearly says JT#2-1/2 and I've concluded that at one time it may have been a MT but they never changed the manual.
Norm
Reply to
Norm Dresner
| | > Done. The manual is there under the name AMT 4030 Drill Press. | > | > Norm | | We shoulda got that done right in the beginning. Sure would have saved | some back and forth. | | Nice size scan, by the way, clear enough to read and still fast to get | on cruddy dialup. |
FWIW, I have a Canon 9950F scanner with ScanSoft OmniPage SE 2.0 which was used to create a Word version of the document which I then threw into Acrobat 7.0 to make the PDF. I'd guess that the conversion to text done at the start of this is responsible for keeping the size down.
Norm
Reply to
Norm Dresner
LOL! Norm still trolling? I told him a couple of weeks ago that he has a drill with a Din standard chuck mount, which incidentally uses a shortened version of the Morse Taper.
Tom
Reply to
Tom
| > | > Norm Dresner wrote: | > | > > Done. The manual is there under the name AMT 4030 Drill Press. | > > | > > Norm | > | > We shoulda got that done right in the beginning. Sure would have saved | > some back and forth. | > | > Nice size scan, by the way, clear enough to read and still fast to get | > on cruddy dialup. | > | > I wonder if that really is a section of a morse taper that they used on | > the spindle. Doesn't much matter, as it seems unlikely that there are | > any chucks available to fit it as is. | > | > As I said before, the amount of runout you say is present is an awful | > lot less than I would expect to find on a small drill press, and I doubt | > I would have been doing anything about it without some compelling | > reason, like a munged up chuck. | > | > Got a lathe and a toolpost grinder? Know anyone that has a tool and | > cutter grinder or cylindrical grinder? | > | > To the makers credit, they built a nut in to remove the chuck with. Too | > bad they could not see fit to use a standard size chuck mount. | > | > Cheers | > Trevor Jones | | LOL! Norm still trolling? I told him a couple of weeks ago | that he has a drill with a Din standard chuck mount, which | incidentally uses a shortened version of the Morse Taper. | | Tom
The measurements are nothing like any Morse Taper on the books. Or don't you care about measurements?

Reply to
Norm Dresner
That you can find, perhaps? If you actually listened and then addressed yourself to looking up DIN standards for drill chuck mounts you might begin understand what you have. That they use the Morse Taper angularity doesn't make them part of the Morse Taper Standard.
Reply to
Tom
DIN? Ive never seen them. Euro stuff I take it?
Gunner
"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences." - Proverbs 22:3
Reply to
Gunner
Hi Norm,
I've been following this discussion for the while and I finally had to go take a look in the dungeon. I see some more ideas/info has popped up since I wrote this too...
I have two presses wearing AMT badges and they are probably the same as yours. Here is an image for comparison:
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These were both made in Taiwan. See the following image of one of the name plates and note "Made in" at the bottom of the plate. The company American Machine and Tool Inc is in PA, but these weren't made there.
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One instruction sheet (that came with them) does indeed mention using a Morse taper, the other machines sheet says Jacobs taper. The two chucks are of different manufacture and are inexpensive no names. Neither one is marked as to the taper they use.
These were inexpensive presses and weren't even sold with motors on them.
For anyone curious, here is a parts diagram showing the chuck, quill, spindle, pulleys... It appears that you are stuck with this taper, it is part of the spindle.
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From the measurements you made and my trying a JT2 and JT33 on one of my presses (both too small, only other chucks I had on hand), I would say that this is a JT6 taper. See this file from Jacobs, which also has the "din" measurements mention in another post:
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They show the size progression as JT2 to JT33 to JT6 to JT3.
The JT6 is listed as:
Large Dia Small Dia Length .678 .6241 1.000
My presses are really sloppy. If you lower the quill an inch or so, you can grab the chuck and move it back-and-forth maybe a 1/16 inch. Have you tried that on yours?
There is a set screw and locknut on the side of the casting, but even adjusting that you can't get rid of the play. You get what you pay for and these weren't much (shrug).
It looks like if you could find another JT6 taper chuck you would be in business. I wouldn't bother on mine, not with the slop I've got in the quills...
Reply to
Leon Fisk

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