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" --- my AMT
#3 .8100" .7461" 1.2188

It's also not anything close to any Morse taper either, nor a B+S.

I guess it really is a JT#2-1/2 and nothing else.

Which means that there's no way that I can replace the chuck with anything
better today.

Also, in removing the chuck, I discovered that the set screw that holds the
pulley to the shaft was missing so all speeds under load were slower than I
thought they were. I doubt that this had any effect on the runout, but I
will measure it after replacing the chuck just to make sure that I haven't
made it worse.

Norm

"Norm Dresner" wrote in message
...
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.

Perhaps you're over reacting.

It's also not anything close to any Morse taper either, nor a B+S.

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

Norm Dresner wrote:

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.

Nobody thought you were crazy. The reaction you posted to the first
question, though...


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" --- my AMT
#3 .8100" .7461" 1.2188

It's also not anything close to any Morse taper either, nor a B+S.

I guess it really is a JT#2-1/2 and nothing else.

Which means that there's no way that I can replace the chuck with anything
better today.

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.

Also, in removing the chuck, I discovered that the set screw that holds the
pulley to the shaft was missing so all speeds under load were slower than I
thought they were. I doubt that this had any effect on the runout, but I
will measure it after replacing the chuck just to make sure that I haven't
made it worse.

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


Norm

"Trevor Jones" wrote in message
...
| 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

Norm Dresner wrote:

"Trevor Jones" wrote in message
...
| 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
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.

http://www.kbctools.com/usa/Navigati...fm?PDFPage=381 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.

http://www.beautifuliron.com/mttaper.htm has what you need to know.

Cheers
Trevor Jones

jim rozen wrote:

In article , Trevor Jones says...

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.

lurk off

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.


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

"Trevor Jones" wrote in message
...
| 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

Norm Dresner wrote:

"Trevor Jones" wrote in message
...
| 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
www.metalworking.com 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

"Trevor Jones" wrote in message
...
| Norm Dresner wrote:
|
| "Trevor Jones" wrote in message
| ...
| | 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
| www.metalworking.com 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

"Norm Dresner" wrote in message
...
| "Trevor Jones" wrote in message
| ...
|| Norm Dresner wrote:
||
|| "Trevor Jones" wrote in message
|| ...
|| | 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
|| www.metalworking.com 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

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

Norm Dresner wrote:
| 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...

"Lew Hartswick" wrote in message
.net...
| Norm Dresner wrote:
| | 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

"Trevor Jones" wrote in message
...
| 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.
|

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

Trevor Jones wrote:

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

"Tom" wrote in message
...
| Trevor Jones wrote:
|
| 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?

Norm Dresner wrote:

"Tom" wrote in message
...
| Trevor Jones wrote:
|
| 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?


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.

On Tue, 14 Mar 2006 12:37:57 +1300, Tom wrote:

Norm Dresner wrote:

"Tom" wrote in message
...
| Trevor Jones wrote:
|
| 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?


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.


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

On Fri, 10 Mar 2006 17:47:35 GMT, "Norm Dresner"
wrote:

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" --- my AMT
#3 .8100" .7461" 1.2188

It's also not anything close to any Morse taper either, nor a B+S.

I guess it really is a JT#2-1/2 and nothing else.

Which means that there's no way that I can replace the chuck with anything
better today.

Also, in removing the chuck, I discovered that the set screw that holds the
pulley to the shaft was missing so all speeds under load were slower than I
thought they were. I doubt that this had any effect on the runout, but I
will measure it after replacing the chuck just to make sure that I haven't
made it worse.

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:

http://www.iserv.net/~lfisk/amt-pair.jpg

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.

http://www.iserv.net/~lfisk/amt-nameplate.jpg

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.

http://www.iserv.net/~lfisk/amt-diagram.gif

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:

http://www.jacobschuck.com/pdf/Techn...nformation.pdf

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...

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

Okay, so I'm late and catching up, but Gunner
wrote on Tue, 14 Mar 2006 03:11:54 GMT in rec.crafts.metalworking :

The measurements are nothing like any Morse Taper on the books. Or don't
you care about measurements?

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.


DIN? Ive never seen them. Euro stuff I take it?

German. ANSI fur Deutschlander.

--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."

According to Norm Dresner :

"Trevor Jones" wrote in message
...
| 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.

I don't think that anyone doubted you. We were simply hoping
that the drill press spindle was made in such a way as to allow
a replaceable arbor, so it would be easy to change to other Jacobs taper
sizes. (And some of your earlier terminology suggested that it was so
equipped.)

Since there is no such feature, you are stuck with your existing
chuck (which, IIRC, was not that bad for a typical drill press chuck) --
especially the ones from China and Taiwan.

It *might* be that the same manufacturer made a version of the
drill press with a spindle with a Morse taper socket -- and if so,
changing one of those into the drill press might increase your options.

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

According to Norm Dresner :
"Norm Dresner" wrote in message

[ ... ]

| I'm scanning it right now and I'll drop it in as a 3-page .PDF file for
the
| whole manual.

[ ... ]

Done. The manual is there under the name AMT 4030 Drill Press.

O.K. I see where some of the confusion came from. The manual
calls the Jacobs taper on the end of the spindle a Morse taper -- which
is totally incorrect.

Also -- it is a smaller drill press than I was considering, so a
Morse taper in the spindle is quite unlikely. There just is not room
for one of reasonable size. My floor-standing one only has a MT-2, and
I would prefer a MT-3 in that one. Yours *might* accommodate a MT-1,
but that would be too small to be worth the trouble.

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote:

According to Norm Dresner :
"Norm Dresner" wrote in message

[ ... ]

| I'm scanning it right now and I'll drop it in as a 3-page .PDF file for
the
| whole manual.

[ ... ]

Done. The manual is there under the name AMT 4030 Drill Press.

O.K. I see where some of the confusion came from. The manual
calls the Jacobs taper on the end of the spindle a Morse taper -- which
is totally incorrect.
...............

Good Luck,
DoN.

Actually it could be correct, Don.

According to Jacobs:

"DIN Taper Interchangeability
DIN tapered sections are identical to the following Morse tapers:

MT No 1 for tapers B10 and B12
MT No 2 for tapers B16 and B18
MT No 3 for tapers B22 and B24

The length of these tapers is, of course, distinctly less than the
overall length of the corresponding Morse taper. Each taper may be
regarded as corresponding approximately to that part of the Morse
taper nearest the small end(for example: B10), or to the part nearest
the large end (for example: B12)"

Tom

According to Tom :
"DoN. Nichols" wrote:

[ ... ]

O.K. I see where some of the confusion came from. The manual
calls the Jacobs taper on the end of the spindle a Morse taper -- which
is totally incorrect.

[ ... ]

Actually it could be correct, Don.

According to Jacobs:

"DIN Taper Interchangeability
DIN tapered sections are identical to the following Morse tapers:

MT No 1 for tapers B10 and B12
MT No 2 for tapers B16 and B18
MT No 3 for tapers B22 and B24

The length of these tapers is, of course, distinctly less than the
overall length of the corresponding Morse taper. Each taper may be
regarded as corresponding approximately to that part of the Morse
taper nearest the small end(for example: B10), or to the part nearest
the large end (for example: B12)"

Intersting information. Of course, it still should not be
*called* a Morse taper, as that leads to the expectation of a socket in
the spindle, and a certain length, neither of which is met.

I wonder whether the choice of basing the DIN tapers on the
Morse tapers is because there were plenty of precise gauges already
around for checking the taper?

And I'm still wondering where that 2-1/2 Jacobs taper came from
on the machine's label -- and a taper which appears to be closer to that
than anything else, even though there is no mention of a 2-1/2 Jacobs
taper in _Machinery's Handbook_ -- at least not in the 25th edition.
Just a "No. 2 short taper", which is not truly a half of a #2 taper. :-)

Enjoy,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"Leon Fisk" wrote in message
...
| 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:
|
| http://www.iserv.net/~lfisk/amt-pair.jpg
|
| 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.
|
| http://www.iserv.net/~lfisk/amt-nameplate.jpg
|

Yes, Leon, those are the exact same "models" that I have. I've posted my
scan of the "manual" in the dropbox at
http://www.metalworking.com
and the measurements I made in the accompanying text file.

Yes, it certainly appears to be a JT6. Knowing that, I searched Enco
http://www.use-enco.com
for JT6 chucks and came up with 4 ranging from $18 to $84 at
http://www.use-enco.com/CGI/INLMK32?PARTPG=INSRAR2

so there may be new chucks available after all.

Thanks very much for the info

Norm

On Wed, 15 Mar 2006 14:10:01 GMT, "Norm Dresner"
wrote:

"Leon Fisk" wrote in message
.. .
| 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:
|
| http://www.iserv.net/~lfisk/amt-pair.jpg
|
| 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.
|
| http://www.iserv.net/~lfisk/amt-nameplate.jpg
|

Yes, Leon, those are the exact same "models" that I have. I've posted my
scan of the "manual" in the dropbox at
http://www.metalworking.com
and the measurements I made in the accompanying text file.

Yes, it certainly appears to be a JT6. Knowing that, I searched Enco
http://www.use-enco.com
for JT6 chucks and came up with 4 ranging from $18 to $84 at
http://www.use-enco.com/CGI/INLMK32?PARTPG=INSRAR2

so there may be new chucks available after all.

Thanks very much for the info

Hi Norm,

Is you're press badged as made in Taiwan too (now that you
know where to look)? I don't think mine are quite as old as
yours, probably bought in the mid to late 70's. They are
subtly different too. The slightly newer one doesn't have
the nut for removing the chuck, nor any threads for one. The
manual that came with that press still pictures it in the
parts diagram/list though. Instructions for removing the
chuck still tell you to turn the non-existent nut too. This
is also the manual that calls it a Jacobs taper. Just
eyeballing them though it appears to be the same taper. I
only popped off the chuck on the press that has a threaded
nut

You might want to check how much play there is when you run
the quill down and inch or two. As I mentioned, mine are
really loose. I don't know what the other readers opinions
are, but for drilling tiny holes I don't think this would be
a good thing.

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

Not sure if anyone else posted on this (I'm 2500 posts behind in my reading)
but the measurements of the J2-1/2 sure do look the same as the J6 which you
don't show.

If they are the same, you can get a J6 chuck...

Regards,
Joe Agro, Jr.
(800) 871-5022
(908) 542-0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com

V8013-R


"Norm Dresner" wrote in message
...
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" --- my AMT
#3 .8100" .7461" 1.2188

It's also not anything close to any Morse taper either, nor a B+S.

I guess it really is a JT#2-1/2 and nothing else.

Which means that there's no way that I can replace the chuck with anything
better today.

Also, in removing the chuck, I discovered that the set screw that holds
the
pulley to the shaft was missing so all speeds under load were slower than
I
thought they were. I doubt that this had any effect on the runout, but I
will measure it after replacing the chuck just to make sure that I haven't
made it worse.

Norm

replying to Norm Dresner, kevin wrote:
We're you able to find a replacement for the 2 1/2 in Chuck , too am looking
for one

--
for full context, visit http://www.polytechforum.com/metalwo...at-480470-.htm

replying to kevin, chris wrote:
I replaced my missing chuck that has the the same spindle listed as a JT#
2-1/2 with an Amazon chuck -----
https://www.amazon.com/POWERTEC-7110...c+jt%236+chuck
I hope this helps

--
for full context, visit http://www.polytechforum.com/metalwo...at-480470-.htm

replying to chris, Elden wrote:
Chris,
I realize that you posted your response more than 2 years ago, but I would
like to ask you a question. Did the chuck you used grip the spindle well or
did it ever slip during heavy use?
The drill press I have calls for the JT#2 1/2 as well. It has worn to the
point that one has difficulty getting it tight enough with the chuck key to
prevent slippage on the drill bit.
I used an online calculator for finding taper angles
(http://www.magafor.com/841/uk.htm) to compare the two Jacob Tapers. Using the
specifications for the JT #2 1/2 and for the JT #6 that I found, they were
plugged into the calculator. The values obtained we JT #2 1/2 2.82°
cone angle or 4.929% taper; JT#6 2.97° cone angle or 5.191% taper. The
differences were 0.15° for the cone angle and 0.262% taper.
I realize that the differences are small, but they are the reason for my
initial question. I would like to know from someone who has actually put it to
a prolonged test whether it is a workable solution.

Thank you for your time,
Elden

--
for full context, visit https://www.polytechforum.com/metalw...at-480470-.htm

replying to Elden, Chitty wrote:
Revisiting this thread- did anyone verify using a jt6 chuck on the one piece
jt 2 1/2 spindle? Im fighting this same question....

--
for full context, visit https://www.polytechforum.com/metalw...at-480470-.htm