I am looking for a little input in case I have missed something. I found
an old J-line bowl lathe and bought it. I am have been looking for a
motor to power it. I have looked at a bunch of motors, controllers, AC,
DC, 3-phase, single phase etc. I think I have settled on a DC motor
largely because of cost. After some searching and a lot of scrap paper
math I think I have made my choice. I have found a 1 HP totally enclosed
motor, 1725 RPM, sealed unit and rated for continuous duty. It costs
more than some of the other DC motors but it seems the better choice in
a dusty environment like a lathe. It

Having no experience with DC motors I have some concerns about the loss
of low speed torque. My plan is to run a variable speed control and
since my lathe came with a 3 step pulley on it and I I have decided to
use pulleys with a 3", 4" and 5" diameter and a second one with a 1
5/16", 2 9/16" and 3 3/8" dia. That way If I need to I can run the motor
at a higher speed and keep the spindle speed down and torque up.

On the lowest setting my max. spindle speed would be 455 RPM and I have
close to a 4 to 1 multiplication factor in my favor, so even at very
slow speeds I should still have plenty of torque. The next step provides
for 1120 RPM and a 2 to 3 ratio. The highest setting is almost 1 to 1
and would be way faster than I think I would ever need.

While I hope to just set it and not have to change the belt location at
least if I find that at slow speeds on larger items that I am lacking
torque I have the option to gear it down and speed up the motor. Or have
I missed something here?

Kudzu,
I am not familiar with your lathe, but have a few comments. Variable
speed is a luxury that once you have it, you can't imagion turning
without it. I like speeds down to 0 and up to 3000. 500 rpm is very
fast for a chainsawn 12 inch diameter blank. Unless the lathe is very
heavy, you may end up chasing it aroung the shop. For a 18 inch bowl
blank, it is down right scary. For turning 1x12 inch spindles, 1000 rpm
is very slow, 3000 or more is fine. The speed sounds scary, but when
you think about it, it is a matter of 'feet per minute'. A 12 inch bowl
at 500rpm is going at the same of more fpm than a 1 inch spindle (I
didn't do the exact math, but you get the idea). The more I turn, the
more comfortable I am at higher speeds, as long as the lathe and what I
am turning isn't shaking too much. If all of your turnings are
perfectly balanced, 500 rpm is fine. It is nice to start out at 0, and
up the speed slowly to see how well balanced and secure the blank is
before you begin to turn.
robo hippy

"robo hippy" wrote in message
oups.com...
SNIP
For turning 1x12 inch spindles, 1000 rpm
is very slow, 3000 or more is fine. The speed sounds scary, but when
you think about it, it is a matter of 'feet per minute'. A 12 inch bowl
at 500rpm is going at the same of more fpm than a 1 inch spindle (I
didn't do the exact math, but you get the idea). The more I turn, the
more comfortable I am at higher speeds, as long as the lathe and what I
am turning isn't shaking too much.

SNIP

Roy Underhill is on in an hour and a half. Love watching him take a curl
off while rotating the piece at less than 1 rpm....

"Kudzu" wrote in message
...
I am looking for a little input in case I have missed something. I found an
old J-line bowl lathe and bought it. I am have been looking for a motor to
power it. I have looked at a bunch of motors, controllers, AC, DC, 3-phase,
single phase etc. I think I have settled on a DC motor largely because of
cost. After some searching and a lot of scrap paper math I think I have
made my choice. I have found a 1 HP totally enclosed motor, 1725 RPM,
sealed unit and rated for continuous duty. It costs more than some of the
other DC motors but it seems the better choice in a dusty environment like
a lathe. It

Having no experience with DC motors I have some concerns about the loss of
low speed torque. My plan is to run a variable speed control and since my
lathe came with a 3 step pulley on it and I I have decided to use pulleys
with a 3", 4" and 5" diameter and a second one with a 1 5/16", 2 9/16" and
3 3/8" dia. That way If I need to I can run the motor at a higher speed
and keep the spindle speed down and torque up.

On the lowest setting my max. spindle speed would be 455 RPM and I have
close to a 4 to 1 multiplication factor in my favor, so even at very slow
speeds I should still have plenty of torque. The next step provides for
1120 RPM and a 2 to 3 ratio. The highest setting is almost 1 to 1 and
would be way faster than I think I would ever need.

While I hope to just set it and not have to change the belt location at
least if I find that at slow speeds on larger items that I am lacking
torque I have the option to gear it down and speed up the motor. Or have I
missed something here?

I think you should be OK to the extent that it is worth a try. You might
find you do want more than 1725 rpm sometimes for small diameter stuff. I
wonder if the 1-5/16" dia pulley is going to get enough grip on the belt to
start rotating a big blank - I have a small pulley on my bandsaw and it can
be a problem slipping.

Are you using a commercial DC motor controller? They should have a better
torque/constant speed characteristic than just varying the DC voltage
open-loop.

Good luck,
Billh

I agree with r h, Starting from zero rpm or even varying the speed
between belt changes was once a luxury and still may be for mini lathes,
but IMO for today's larger lathes, the luxury has become a necessity.
Reminds me of the 'luxury' of powering the brakes, steering and windows
on cars. I thought when they first came out they were just luxury lily
gildings. Same with scroll chucks, revolving tail centers and grinding
jigs.
My dad probably felt the same way about self starters and Skill Saws, a
crank and a Disston were 'good enough' for him.

I won't bring up the Luxury of movable headstocks or lathe beds. Too
many of my friends have "Noway" to do this and besides I'm not in COC
mode.


Turn to Safety, Arch
Fortiter



http://community.webtv.net/almcc/MacsMusings

Well the lathe is a casting and about 50 lbs. Not heavy enough for
nothing. But I am building a stand for it and I plan on making it very
sturdy and with a place to add sand bags for weight. I am going to start
at 300 lbs or so and go from there. After all sand is cheap.

If you want to see a photo of the lathe here is the URL
http://www.kudzupatch.com/temp/bowl_lathe2.jpg It's just sitting on my
table saw outfeed table. Of course the key to this is going to be the
stand it's on. It will make or break it.

BTW I used to be a mechanical designer in a previous life so I am very
familiar with Surface Feet per minute and totally agree with you on the
speeds. I have turned a few rough blanks on a on craftsman lathe with no
weight and not enough slow speed. Scared the hell out of me when I hit
the on switch!

I am not sure if you understood or not but I should have speed of 0 and
up with the speed controller

Well my top speed, if I use the fastest combination is 1977RPM. I don't
expect to do much small stuff on this lathe. I 'expect' to just be
turning larger bowls and hollow forms. But you never know of course. I
am looking for a Delta/Rockwell lathe to go with this one. I want to add
riser blocks to it. This lathe is not suitable for spindle work as it
has no tail center. I see down the road using both lathes in conjunction
with one another.

Interesting point about the small pulley. Had not thought of that. I can
go with a 2 inch and 6 inch on the second pulley and get about the same
speeds but a 6" won't fit in the existing guard. I can of course build a
new guard but really don't want to do that. I am hoping/expecting that I
won't have to use the smallest pulley at all.

The motor controller is a Reliance Electric 230V pulse width modulated
controller. I found it at the www.surpluscenter.com. I am can the motor
and controller for $200. The motor is matching Reliance commercial
model, not one of the treadmill motors. I looked at those and decided
against it. Plus I really like the TEFC enclosure on a lathe.

"robo hippy" wrote:

The more I turn, the
more comfortable I am at higher speeds, as long as the lathe and what I
am turning isn't shaking too much.

Which is where zero to X variable speed really shines: you tune the speed
for the work.

Hi Kudzu,
Seeing the picture changes the approach I would take. For me your lathe
is a wonderful piece of machinery to enjoy and restore to what it was.
Please don't take this as a put down, I would love to own it. I don't
know what a J line is, but unless the pic is very misleading it was
designed for light & balanced turning, perhaps for a special purpose.
Maybe it is wooden bed spindle lathe with tailstock missing. Maybe it is
a disc or platter lathe. Maybe I'm lost out in left field.

For general bowl turning in the 14- 16 in, size the spindle and tool
post 'appear' undersized. The toolrest 'appears to have little or no
vertical adjustment. The head casting doesn't 'appear' to be very robust
and the bed 'appears' short even for a bowl lathe. Maybe like so many
'heavy duty' 1/4 hp split phase home workshop power tools of yesteryear,
it never really was HD, but it sure is a fascinating lathe.

I have no training in mechanics or in machine design, but there must a
limit to what a heavy and well engineered stand, slow speed and
increased hp can do, else we would all construct massive stands, put 50
lb lathes with jack shafts and 3 hp motors on them and turn big heavy
bowl blanks.

Can you tell us more about your interesting J line lathe. I may have the
specs and what should be done entirely wrong and my take may be a waste
of bandwidth. (not the first time) Whatever you decide to do, have fun
and tell us about it.


Turn to Safety, Arch
Fortiter



http://community.webtv.net/almcc/MacsMusings

Hi Arch

I think you are absolutely right Arch, you can see the lathe is well
made , but is not made for anything heavy, stool top or small table top
or such come to mind.
If one would try to turn some rough blanks on it the first catch would
break the banjo, and I think that would be a shame, much better to
restore and use for it's designed purpose than to try to make it do what
it's unable to do, however I am not the one to decide here.

Have fun and take care
Leo Van Der Loo

Arch wrote:
Hi Kudzu,
Seeing the picture changes the approach I would take. For me your lathe
is a wonderful piece of machinery to enjoy and restore to what it was.
Please don't take this as a put down, I would love to own it. I don't
know what a J line is, but unless the pic is very misleading it was
designed for light & balanced turning, perhaps for a special purpose.
Maybe it is wooden bed spindle lathe with tailstock missing. Maybe it is
a disc or platter lathe. Maybe I'm lost out in left field.

For general bowl turning in the 14- 16 in, size the spindle and tool
post 'appear' undersized. The toolrest 'appears to have little or no
vertical adjustment. The head casting doesn't 'appear' to be very robust
and the bed 'appears' short even for a bowl lathe. Maybe like so many
'heavy duty' 1/4 hp split phase home workshop power tools of yesteryear,
it never really was HD, but it sure is a fascinating lathe.

I have no training in mechanics or in machine design, but there must a
limit to what a heavy and well engineered stand, slow speed and
increased hp can do, else we would all construct massive stands, put 50
lb lathes with jack shafts and 3 hp motors on them and turn big heavy
bowl blanks.

Can you tell us more about your interesting J line lathe. I may have the
specs and what should be done entirely wrong and my take may be a waste
of bandwidth. (not the first time) Whatever you decide to do, have fun
and tell us about it.


Turn to Safety, Arch
Fortiter



http://community.webtv.net/almcc/MacsMusings

Kudzu wrote:
Well my top speed, if I use the fastest combination is 1977RPM. I don't
expect to do much small stuff on this lathe. I 'expect' to just be
turning larger bowls and hollow forms.

Can you quantify 'large' bowl? And what is the diameter of the headstock
spindle? So much depends on the spindle and the headstock construction.
You can put all the weight you like in the bench, but if the spindle and
bearings aren't up to the job of handling a large bowl, or hanging a
hollow vessel off the end, you are wasting time and energy shovelling
sand I'm no mechanical engineer, just speaking from experience of
using inadequate lathes.

It is really difficult to get any idea of scale from the photo, but it
does look flimsy to me. I agree with Arch's comment:

"unless the pic is very misleading it was designed for light & balanced
turning, perhaps for a special purpose. Maybe it is wooden bed spindle
lathe with tailstock missing. Maybe it is a disc or platter lathe."



--
Derek Andrews, woodturner

http://www.seafoamwoodturning.com
http://chipshop.blogspot.com
http://groups.yahoo.com/group/toolrest/

I have a 1 hp, 5000 rpm motor and it works real well for most things with
speeds in 3 pulley settings approximately the same as yours. This is
obtained with a jackshaft. I have turned up to 18 inch bowls and you can
turn it down slow enough to be very comfortable. My top speed in top pulley
setting is 2000 rpm and the top speed at lowest pulley setting is between
400 and 500 rpm, so just about the same. My motor and controller cost me
$50 or so from Vega when they bought a whole bunch of surplus. I can
actually turn it down to something ridiculous like 1-10 rpm or less in the
lowest pulley setting.

I have a reversing switch and a potentiometer mounted in a white painted box
from a home store. I bought a blank faceplate for the box and drill holes
for these in the face. The wires are in a split, corrugated flexible tube
like used in some autos. I epoxied magnets on the back of the box and can
move it to different positions on the lathe.

I turn only bowls and sometimes I wish my speeds were a little lower so I
could be at the full 1 hp more of the time. Pens and tiny objects might
want over 2000 rpm. The larger the motor you get, the less optimized your
pulley ranges need to be.

Derek

My Internet service has been down. I was on the tractor doing some
landscaping and came in the house to find no TV or Internet. It seems
that they didn't bury the cable very deep. DAMHIKT. :-)

OK, I was fortunate to actually get the manual with this lathe. It was
made by Brodhead-Garret of Cleveland Ohio and is called a J-Line Bowl
lathe Model J-116. There is no date in the manual unfortunately but the
book makes me think 1940's. Arch, your very much on track and bring up
some good points that in my excitement I must admit I have not
considered. The manual doesn't have much information in it on the lathe
itself. It concentrates on instructing "how to turn". The lathe was
clearly made as a bowl lathe for making bowls, platters etc. The lathe
was clearly intended (based on the manual) for faceplate turning. It
doesn't mention what it came with in the manual but mine has (3) 7"
faceplates

The manual shows diagrams of large bowls (14" dia), platters, hollow
form (6" long) and even some plans for a set of Bongo Drums. (That might
date it to the 50's??) I had not thought about the fact that it was not
intended for rough blanks but I do think you are correct. There is
mention about gluing up blanks, sawing them round etc. It has a 3/4"
spindle and the castings, while not very heavy do appear to be very strong.

As for the Banjo it was/is a point of concern for me too. I have been
toying with building (welding) something stronger and with some height
adjustment on it.That way I don't damage the original and I can do more
with the lathe. I bought it use but I don't want to ruin it either or do
an permanent modifications to the lathe.. I have no problem with someone
that would take this and restore it to like new, I just hate to see one
not used then.

After giving it some thought while writing this I guess I am going to
have to change my plans for this lathe. I think I was so excited to get
it that I did not really think this through and consider the limitations
of the lathe.. But that is why I asked for advice too!

The manual recommends a 1/2 HP motor but I don't have one that size and
I still love the thought of variable speed even it it is not original to
the lathe. Coming to my senses makes the slower speeds less important if
I start out with round and reasonably balanced blanks. I have a bandsaw
so I can trim up my blanks before putting them on the lathe but I still
love to do natural edge bowls and I think with some care that shouldn't
be a problem as they are not all that much out of balance. I guess I
will just have to start slow and see what it is capable of.

I assume no one will ban from the group if I mount a chuck on here? :-)

BTW I am looking for a Delta/Rockwell lathe (Big heavy one, like the
46-450) with the variable speed control that I can add riser blocks
too. So I can do an serious chainsawed, out of balance blocks on that
lathe, once I find one.

Anxious for you input!

"Kudzu" wrote in message
...

OK, I was fortunate to actually get the manual with this lathe. It was
made by Brodhead-Garret of Cleveland Ohio and is called a J-Line Bowl
lathe Model J-116. There is no date in the manual unfortunately but the
book makes me think 1940's. Arch, your very much on track and bring up
some good points that in my excitement I must admit I have not
considered. The manual doesn't have much information in it on the lathe
itself. It concentrates on instructing "how to turn". The lathe was
clearly made as a bowl lathe for making bowls, platters etc. The lathe
was clearly intended (based on the manual) for faceplate turning. It
doesn't mention what it came with in the manual but mine has (3) 7"
faceplates


Sadly, I believe I can recall advertisements for the J-Line (will you
believe I learned to read very early?) in Popular Mechanics and similar
publications. Fifties is the time frame. Perhaps if you checked an index
you'd find something like a review.