Jet Model JWL-1236 and Delta Model 46-700 and 46-701
Pat Thaler Bill Thomas Jared Thaler Leor Thomas Avi Thomas
FYI
/*----------------------------------------------------------------------------*/
Jet Model: JWL-1236
Capacities
Swing Over Bed: 12 inches
Swing Over Tool Rest Base: 8.75 inches
Working Distance Between Centers: 34.5 inches
Outboard Turning: up to 16.5 inches
Speeds (RPM): 550-3000
Spindle
Nose (inches x T.P.I.): 1x8
Hole completely through spindle: .375 inches
Headstock Taper: MT-2
Tailstoack Taper: MT-2
Hole Through Taper: .375 inches
Motor: .75 HP, 1 Phase , 115V Only
Net Weight: 183 lbs.
Standard Equipment
Open style rigid stand
12 inch tool rest
6 inch face plate
Spur center
Live center
Tooling knockout bar
Face shield
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Delta Model 46-700 and 46-701
Capacities
Swing Over Bed: 12 inches
Swing Over Tool Rest Base: 8.25 inches
Working Distance Between Centers: 36 inches
Outboard Turning: up to 16x4 inches
Speeds (RPM): 500-2000
Spindle
Nose (inches x T.P.I.): 1x8
Hole (completely through spindle: .625 inches
Headstock Taper: MT-2
Tailstoack Taper: MT-2
Hole Through Taper: .31 inches
Spindle Travel: 2 inches
Motor: .75 HP, 1 Phase, 1725RPM
Net Weight Model 46-700: 125 lbs. Net Weight Model 46-701: 148 lbs.
Standard Equipment
No stand for model 46-700 Model 46-701 has open style rigid stand
12 inch tool rest
3 inch face plate
Drive center
Ball Bearing live center
Knock-out bar
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Andy Cohen
While the specs for the two lathes shows relatively small
differences...i.e., the RPMs, weight, options Vs std equipment (although
the rest extension was left out of the specs for the Jet). There are a
couple of things about operating that are not mentioned. For example it
takes seconds to pivot the head on the Jet, while the Delta requires the
use of a large hex tool and possibly bed removal from a home made bench
to get access. Also, can the Delta knockout the center on the tailstock
when the tailstock is moved all the way in as the Jet? (I don't know, it
didn't work on the display Delta at the store)
The Jet tailstock has complete front and back faces while the Delta has
just the front face(less mass), but the more convenient control position
in the front to move the tailstock. The tool rest lock on the Delta has
a faster operation with a much more comfortable grip.
I came VERY close to going with the Delta, but in the end when I started
to consider buying the stand for the delta(add $55), then noticed the
need to also purchase the rest extension for outboard turning I found it
too close in price to ignore the headstock pivot and better rpm rating
on the Jet. After weeks of careful consideration and failure to find a
good used lathe I went with the Jet which I got for $499(Vs the Delta
which was on sale for $425 and a $25 rebate).
Dee Smith
My experience with the Delta is that the live center that
came with the lathe and the Nova live center both are NOT
ejected by the tail stock but the drill chuck that I got
from Craft Supplies is ejected. I believe that the difference
is in the length of the Morse taper. The Nova center is
hollow and that may play a role but I don't know for sure.
By the way, it is difficult to remove the Nova center because
it is hollow and you can not use a knock out bar. I have been
using a bar to wedge it out but that pushes unevenly against
the bearings which worries me. If anyone has some suggestions
I sure would like to hear them.
Dee
--
Dee Smith
Software Server Integration Test
IBM Austin, Tx
Robert G. Hamilton
Dee Smith <dees...@austin.ibm.com> wrote:
>My experience with the Delta is that the live center that
>came with the lathe and the Nova live center both are NOT
>ejected by the tail stock but the drill chuck that I got
>from Craft Supplies is ejected. I believe that the difference
>is in the length of the Morse taper. The Nova center is
>hollow and that may play a role but I don't know for sure.
>By the way, it is difficult to remove the Nova center because
>it is hollow and you can not use a knock out bar. I have been
>using a bar to wedge it out but that pushes unevenly against
>the bearings which worries me. If anyone has some suggestions
>I sure would like to hear them.
>Dee
Dee:
What a coincidence that you should ask this question right now!
I just this morning bought the One-Way live center and gave it a try
this afternoon. It is really smooth, but the morse taper is too short
to auto eject, and has a 5/16" diameter hole running through it so
that a knock out bar (supplied) may be used to remove the center point
of the cup center. This had me turning the air blue the first time I
went to remove it, because there is nothing for the knock-out bar I
have always used to remove my old live center to knock against!
I decided that something had to be done before I used the new center
again, so once I got it out I put my old one back in and turned a plug
for the center hole out of the first small piece of scrap that fell to
hand. I made the plug to be an easy friction fit in the 5/16" hole,
and left a 1/2" diameter section about 1/2" long. I figured this
would give the knock-out bar something to drive against, but I was a
little concerned about how well the walnut plug would hold up to being
driven. My fears were groundless, not because the wood is tough
enough to take the shock of the knock-out bar, but because the extra
1/2" of length is just enough to make the center auto eject!
Bad ascii art alert!
______
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I have the Delta lathe, too, and my experience duplicates yours. The
center that came with the lathe does not auto eject, but the morse
taper that came on my Jacobs chuck does auto eject. The major
difference being that my lather did not come with a live center, just
a dead cup center. It did, however, come with an 8 piece set of
chisels. The cheapo live center I bought 5 years ago looks very
similar to the live center that Delta is supplying with the lathe now,
but it had developed a fair bit of play and I decided it was time for
an upgrade. I do like the two cone centers that came with the
One-Way, although I have yet to use them. Anybody out there got any
tips for their use?
Bob Hamilton
Forest, Ont., Can.
Jim Diamond
Dee Smith <dees...@austin.ibm.com> wrote:
>My experience with the Delta is that the live center that
>came with the lathe and the Nova live center both are NOT
>ejected by the tail stock but the drill chuck that I got
>from Craft Supplies is ejected. I believe that the difference
>is in the length of the Morse taper. The Nova center is
>hollow and that may play a role but I don't know for sure.
>By the way, it is difficult to remove the Nova center because
>it is hollow and you can not use a knock out bar. I have been
>using a bar to wedge it out but that pushes unevenly against
>the bearings which worries me. If anyone has some suggestions
>I sure would like to hear them.
Dee,
I recently had a similar problem when I got a General 260 (whose
tailstock does not allow you to use a knock-out bar). The dead center
supplied with the lathe automatically ejected when I back the
tailstock screw up, but the ball-bearing center (*) I already had
wasn't long enough. My solution was to epoxy a small brass nut on the
end of this center, which made it long enough so that backing up the
tailstock screw ejects the center.
(*) A while back on rec.woodworking someone claimed that any center in
your tailstock (fixed or with bearing) should be termed a "dead
center", since they are not being driven, whereas the spur center in
your headstock would be the "live center", since it is being driven.
Does anyone out there with real machinist training know the definitive
answer?
Jim Diamond
z...@axe.nstn.ca
--
Jim Diamond (z...@atl.sofkin.ca)
Software Kinetics Ltd.
201 Brownlow Avenue, Dartmouth, N.S., Canada B3B 1W2
Phone: (902) 481-4579 Fax: (902) 468-3679
Dee Smith
Jim,
Thanks for your suggestion. I got a somewhat similar suggestion
by email from Bob Hamilton which follows this note. I am thinking
that maybe a 5/16 shoulder bolt inserted in the hollow center
may also do the trick. The head may have to be ground round and
to the correct diameter but should work well.
Dee
From Bob Hamilton:
I just this morning purchased the One-Way live center, and it also has
a hole running all the way through the morse taper to allow the center
point of the cup center to be knocked out. I also have the Delta
lathe, and my experience is identical to yours: the center that came
with the lathe and the One-Way center have too short a morse taper for
them to auto-eject, although the morse taper on the Jacobs chuck I
bought does auto-eject.
I was quite astounded when I tried to remove the One-Way from the
tailstock this afternoon and found how difficult it was. I decided to
rectify the situation by turning a wooden plug for the hole in the
morse taper to give the knock-out bar something to knock against. I
turned a plug that was an easy friction fit in the 5/16" diameter hole
in the taper, and left a section about 1/2" long at 1/2" diameter so
that the plug would not get pushed into the hole. Kind of like a 1/4"
dowel sticking out of the center of a 1/2" dowel.
I was kind of dubious about how long the plug would last being hit by
a knock-out bar, but found that that extra 1/2" of length is just
enough to make the center auto-eject! Bonus!
Hope it works for you!
Bob Hamilton
--
Jim Jones
In article <328A2A...@austin.ibm.com>,
Dee Smith <dees...@austin.ibm.com> wrote:
>My experience with the Delta is that the live center that
>came with the lathe and the Nova live center both are NOT
>ejected by the tail stock but the drill chuck that I got
>from Craft Supplies is ejected. I believe that the difference
>is in the length of the Morse taper. The Nova center is
>hollow and that may play a role but I don't know for sure.
>
>By the way, it is difficult to remove the Nova center because
>it is hollow and you can not use a knock out bar. I have been
>using a bar to wedge it out but that pushes unevenly against
>the bearings which worries me. If anyone has some suggestions
>I sure would like to hear them.
>
>Dee
>
Dee
I have lengthened a live center by drilling into the end of the
morse taper. Tap the hole and add a hex head screw of appropriate
diameter. This will lengthen the morse taper by the heigth of the
head of the screw. I suppose you could increase the length further
by adding washers.
I am not familar enough with the Nova live center to know if you
could tap the hollow morse taper or not. It may be a possibility.
If you have access to a gas welder, you could always tack an
extention to the morse taper.
Jim
Paul C. Dickie
Jim Diamond wrote:
>
> (*) A while back on rec.woodworking someone claimed that any center in
> your tailstock (fixed or with bearing) should be termed a "dead
> center", since they are not being driven, whereas the spur center in
> your headstock would be the "live center", since it is being driven.
>
Pedantically, they are correct -- but, over the years, the term has come to
mean what was once termed a revolving center. Language changes, which is
why we have come to accept that the term "gay" may denote a homosexualist...
Getting back on topic: the term "dead center" (for a non-driven center) goes
back to the days when an engineer's center lathe was literally used to turn
"between centers"; the workpiece was supported by a center at either end
and driven by a "dog" engaging on a catch-plate mounted on the headstock.
Because the tailstock center was fixed, there was a risk of the center
overheating unless that center was lubricated -- which is why center drills
(aka Slocombe drills) cut a short cylindrical bore before they start to cut
the standard 60' center...
--
< Paul >
Mike Paulson
Sender:
Followup-To:
Distribution:
Organization: University of Denver, Dept. of Math & Comp. Sci.
Keywords:
Cc:
>My experience with the Delta is that the live center that
>came with the lathe and the Nova live center both are NOT
>ejected by the tail stock but the drill chuck that I got
>from Craft Supplies is ejected. I believe that the difference
Hi,
I bought the Nova center (highly recommended) for my Delta 46-700 and it
self ejects quite nicely. The cheapo live center that came with the lathe
did not. I just glued a little plug of wood on the end and that solved
the problem. If your Nova center doesn't self eject, it must be a very
near miss. You could probably just build up the end with a little epoxy
or glue on a washer or turn a ring of just about anything to make up the
difference. Use something you can drill through if you want to preserve
the capacity for boring through the tailstock. A stong bond really isn't
an issue because there is no side thrust on the shim, just a little
compression to knock out the morse taper.
-Mike Paulson, Denver Colorado
Mike Paulson
Sender:
Followup-To:
Distribution:
Organization: University of Denver, Dept. of Math & Comp. Sci.
Keywords:
Cc:
For example it
> takes seconds to pivot the head on the Jet, while the Delta requires the
> use of a large hex tool and possibly bed removal
I don't think this is entirely accurate in that it really isn't stated
strongly enough. The Delta is a real pain to swivel the head, with the
Jet is is snap city.
> The Jet tailstock has complete front and back faces while the Delta has
> just the front face(less mass), but the more convenient control position
> in the front to move the tailstock.
The Delta does have a slightly more convenient locking lever on the front
face of the tailstock, but it gets in the way of your tool handles
sometimes and then it doesn't seem so convenient at all.
The observation about more mass in the Jet tailstock holds true for the
headstock as well where it is even more important. The Delta does fine
for turning between centers, but when it comes to hollow forms the
headstock definitely does not have enough mass to handle the stress.
-Mike Paulson
Denver Colorado
Dee Smith
Jim
Those are good suggestions. However, the reason for the hole
in the center is to allow knocking out the interchangable
points and also boring long holes in the work piece with an
auger. You might do this when making a lamp.
Therefore, I would not want to make the length extension
permanent on the hollow Nova center. The Delta center would
be a good candidate for the permanent extension though.
Thanks for the idea.
Dee
Jim Jones wrote:
>
>
> Dee
> I have lengthened a live center by drilling into the end of the
> morse taper. Tap the hole and add a hex head screw of appropriate
> diameter. This will lengthen the morse taper by the heigth of the
> head of the screw. I suppose you could increase the length further
> by adding washers.
>
> I am not familar enough with the Nova live center to know if you
> could tap the hollow morse taper or not. It may be a possibility.
>
> If you have access to a gas welder, you could always tack an
> extention to the morse taper.
>
> Jim
--