Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do you
use? I have a Jet 1442 (reeves) and if it means i can't safely turn a piece
on its lowest speed, I'll have to make a design change.

I know there are many factors to consider here, including balance of the
piece being turned, I'm just looking to see if my lathe's low end is in the
neighborhood.


Thanks,

jc

"Joe" wrote in message
. net...
Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do
you use? I have a Jet 1442 (reeves) and if it means i can't safely turn a
piece on its lowest speed, I'll have to make a design change.


The short answer is no. But if you can get the rough piece pretty close to
balanced you should be able to turn at the capacity of that lathe. I did it
last weekend with a 15" diameter bowl blank on my Jet 1442. What did you
want to turn?

The key is to take off as muc as you can at the band saw, or chain saw.

-Steve


--
Posted via a free Usenet account from http://www.teranews.com

The short answer is no. But if you can get the rough piece pretty close to
balanced you should be able to turn at the capacity of that lathe. I did
it last weekend with a 15" diameter bowl blank on my Jet 1442. What did
you want to turn?

The key is to take off as muc as you can at the band saw, or chain saw.

-Steve

I'm going to be turning a pedestal for a table. It's starting as an
octagon, 9 3/8" min diameter, 10" max diameter. I'm not that worried about
out of balance since I'm leaving non-turned sections (upper and lower), I'll
have to balance it perfectly to start. That'll be the other fun task ;-)

jc

Thanks Steve!

jc

"Steve Russell" wrote in message
.. .
Hello Joe,

Dale Nish came up with a formula many years ago that seems to work very
well. Here is a link to it:

http://www.woodturnerscatalog.com/wo...the_speeds.pdf

Cheers!


On 10/25/07 9:21 AM, in article
, "Joe"
wrote:

Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do
you
use? I have a Jet 1442 (reeves) and if it means i can't safely turn a
piece
on its lowest speed, I'll have to make a design change.

I know there are many factors to consider here, including balance of the
piece being turned, I'm just looking to see if my lathe's low end is in
the
neighborhood.


Thanks,

jc



--
Better Woodturning and Finishing Through Chemistry...

Steven D. Russell
Eurowood Werks Woodturning Studio, The Woodlands, Texas
Machinery, Tool and Product Testing for the Woodworking and Woodturning
Industries

Website: http://www.woodturningvideosplus.com
Free Monthly Woodturning Newsletter * Your email is kept confidential
Sign up at: http://www.woodturningvideosplus.com/lathe-talk.html

On Thu, 25 Oct 2007 14:21:45 GMT, "Joe" wrote:

Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do you
use? I have a Jet 1442 (reeves) and if it means i can't safely turn a piece
on its lowest speed, I'll have to make a design change.

I know there are many factors to consider here, including balance of the
piece being turned, I'm just looking to see if my lathe's low end is in the
neighborhood.


Thanks,

jc

Well, if you want a formula, there's one in the 1442vs manual... *g*

What I was taught years ago still works for me.. Turn at a speed that's
comfortable for you and feels safe..

Raise the speed if you aren't watching the lathe try to walk around and feel
safe at a higher speed...

Probably more important, LOWER the speed if it doesn't feel sage...

I turn at the highest speed that feels safe, not only because of what the folks
here say about more cuts per second or whatever, but because it seems to make me
more patient..
If my tools are sharp and on the wood at a good angle, I can use very light
pressure to cut... but the temptation is to press a bit harder and that's when
your cut goes to hell... I increase the speed and remove more material with a
lighter touch... YMWV

BTW: I'd love to cut the speed range of the 1442 in half, at least...
I have no use for 3,000 and would like something in the 100 to 250 range for
"low" speed..


mac

Please remove splinters before emailing

"Joe" wrote in message
. net...
Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do
you use? I have a Jet 1442 (reeves) and if it means i can't safely turn a
piece on its lowest speed, I'll have to make a design change.

I know there are many factors to consider here, including balance of the
piece being turned, I'm just looking to see if my lathe's low end is in
the neighborhood.


Hmm ... how many angels on the head of a pin depends on the agility of the
angels, the gage of the pin and the vigorousness of the dance. Turning's
no different. On a less than rigid lathe/stand combination, your 500 might
scare you to death on a 10" piece. If you take big bites rather than
shavings you can tear the thing out of the centers, and that means any
speed's going to be too much for you to get out of the way. Out-of-balance
makes everything worse.

Mount those ends carefully, snug them up well and make sure the tail is
locked. I'd say you're best with a ring center, but Darrell's washer might
keep a 60 degree honest. After the first few downhills, stop and recheck.
While the piece is still less than round it can fool you and fling suddenly.
Later you'll have warning, because things won't be smooth like they were.

Keep the rest up close, and it would be good to keep it a tad above center
so you can deflect a dismount below and have little worry of catching your
gouge in the air above the cut. After that, it's whittle from the end back
to center until round, then downhill for pattern. As Dave Hout always
says, don't start in the middle.

If it feels uncomfortably fast, it is. Nothing even Nish says should make
you think you have to cut any faster than what you're comfortable with.
remember, to get the wood coming by twice as fast gives four times the
energy to any mistake. I imagine you're like most of us, moving the gouge
about at a modest speed, not trying to scoop as fast as a high speed would
permit, so enjoy it.

Well, if you want a formula, there's one in the 1442vs manual... *g*

When all else fails, read the instructions.

Okay, I feel foolish, but thanks for all the other advice as well. Lots of
good stuff here.

George, Good advice, I agree with you completely. Well almost
completely. In my turning experience, it's Devils dancing with
Pitchforks instead of Angels with Wings.

Joe, you might want to look in our archives under harmonic balancers. At
one time we had much discussion about them. They seemed easy enough to
fabricate and appeared to work, but haven't been mentioned here in a
while. Perhaps if someone is using one they will pitch in or somebody
will post a reference.
I assume that your lathe's drive doesn't allow for a slipping belt
clutch? If your lathe will swing it, there has to be a way to turn it.
Good luck with your table.


Turn to Safety, Arch
Fortiter


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

No problem. you'll be fine at 450 RPM.

I assume that pedistal will be hollow. It sure would make for a heavy table
otherwise.

-Steve
"Joe" wrote in message
et...

The short answer is no. But if you can get the rough piece pretty close
to balanced you should be able to turn at the capacity of that lathe. I
did it last weekend with a 15" diameter bowl blank on my Jet 1442. What
did you want to turn?

The key is to take off as muc as you can at the band saw, or chain saw.

-Steve

I'm going to be turning a pedestal for a table. It's starting as an
octagon, 9 3/8" min diameter, 10" max diameter. I'm not that worried
about out of balance since I'm leaving non-turned sections (upper and
lower), I'll have to balance it perfectly to start. That'll be the other
fun task ;-)

jc




--
Posted via a free Usenet account from http://www.teranews.com

Here's a web page with a nice chart for turning speeds. I keep it posted
next to my lathe for a good reminder to be safe.
http://turnedwood.com/LatheRPM.htm
Good luck in your turning.

Dan
"Joe" wrote in message
. net...
Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do
you use? I have a Jet 1442 (reeves) and if it means i can't safely turn a
piece on its lowest speed, I'll have to make a design change.

I know there are many factors to consider here, including balance of the
piece being turned, I'm just looking to see if my lathe's low end is in
the neighborhood.


Thanks,

jc

Thanks everyone for your help. Lots of good info here. I'll post pics of
the entire project when finished in abpw.

joe

"Joe" wrote in message
. net...
Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do
you use? I have a Jet 1442 (reeves) and if it means i can't safely turn a
piece on its lowest speed, I'll have to make a design change.

I know there are many factors to consider here, including balance of the
piece being turned, I'm just looking to see if my lathe's low end is in
the neighborhood.


Thanks,

jc

On Thu, 25 Oct 2007 17:30:51 GMT, "Joe" wrote:


Well, if you want a formula, there's one in the 1442vs manual... *g*

When all else fails, read the instructions.

Okay, I feel foolish, but thanks for all the other advice as well. Lots of
good stuff here.


lol.. when I was doing computer consulting, we had a code for that... RTFM..


mac

Please remove splinters before emailing

On Thu, 25 Oct 2007 16:40:37 GMT, "George" wrote:


If it feels uncomfortably fast, it is. Nothing even Nish says should make
you think you have to cut any faster than what you're comfortable with.
remember, to get the wood coming by twice as fast gives four times the
energy to any mistake. I imagine you're like most of us, moving the gouge
about at a modest speed, not trying to scoop as fast as a high speed would
permit, so enjoy it.

Reminds me of something Darrell said on his wing bowl page, about turning them
at 1,900 or thereabouts and that a catch would be "dramatic"..

Brings back a old infantry expression, in response to "no guts no glory"
"No drama, no trauma"


mac

Please remove splinters before emailing

On Thu, 25 Oct 2007 13:50:24 -0400, (Arch) wrote:

I assume that your lathe's drive doesn't allow for a slipping belt
clutch? If your lathe will swing it, there has to be a way to turn it.
Good luck with your table.

One of the things that I don't like about the Reeves drive on these lathes,
Arch... No belt adjustment..

I feel safer turning on the mini, where I can loosen the belt, especially when
I've got a new turner in the shop..


mac

Please remove splinters before emailing

My first lathe had a 4 speed pulley system, so not too many choices.
When I got my PM, it had 2 speed ranges, and viriable speed, but no
readout to tell me how fast I was turning. So, I just turn the speed
up to where it is comfortable for me. Now, a 1 inch spindle feels slow
to me at 3,000 (my max speed) rpm. When turning bowls, to start, I
turn the speed up until it starts to wobble, then back it off a bit.
If I turn a bowl out while it is wobbling, then that wobble is
transfered to the bowl. This is only really important if you are
turning a very thin bowl, sat 1/8 inch or less. If the piece is well
balanced, a 12 inch bowl feels fine at 1500 (max speed in low speed
range) rpm, but an 8 inch bowl feels too slow. 8 years ago, these
speed would have felt way too fast. I have a friend who comes over
once in a while to core some things, and his lathe is one of the
Legacy ornamental ones that has a max speed of 200 rpm. He turns bowls
on my lathe at 200 because that is what he is used to and is
comfortable with. It drives me nuts to see him turn so slow, but that
is what works for him.
robo hippy

On Oct 26, 8:28 am, mac davis wrote:
On Thu, 25 Oct 2007 13:50:24 -0400, (Arch) wrote:
I assume that your lathe's drive doesn't allow for a slipping belt
clutch? If your lathe will swing it, there has to be a way to turn it.
Good luck with your table.

One of the things that I don't like about the Reeves drive on these lathes,
Arch... No belt adjustment..

I feel safer turning on the mini, where I can loosen the belt, especially when
I've got a new turner in the shop..

mac

Please remove splinters before emailing

jc

There's another answer to your question and that is, balance the work
carefully BEFORE you turn on the lathe.

I turn a lot of bowls (on a Jet 1442 by the way). When I take a slab of
tree that's 13" or so in diameter, and 9-10" deep that's a respectable
weight. If it's eccentric it can make that 200# or so pound lathe dance.

What I learned to do, by trial and terror, was to balance the wood BEFORE I
started to turn it. First, I cut off any stuff that makes my skin crawl,
like branch protrusions or other sharp corners that would otherwise need to
be turned off. I put pointed centers in the head and tail stocks, and stick
them into the wood where I think the center is. Only the points penetrate
the wood, so it will pivot on them.

Of course the wood isn't exactly centered and it revolves so that the heavy
part is at the bottom. (Thank goodness for gravity). I then raise the wood
just a bit at one end, and stick the point in, again. Again the wood shows
its unbalance. I keep doing this until the wood will twirl when spun by
hand, without stopping at a particular low point. Then I crank in the
tailstock to make the correct holes deeper than the trial ones.

I take the wood off, and hammer the drive center into the wood, and make a
deep indentation for the tail center. If the wood has bark or
irregularities where the center should go, I use a brace and 1" bit to give
me a good flat surface with a hole for the center.

Its rather impressive to see a 30 to 40 pound irregular piece of wood
spinning at 450
RPM's and the lathe is only gently vibrating.

I've opted not to load the base of my machine with sand or concrete blocks,
on the theory that if I have a load that is so unbalanced that the lathe is
chasing me out the door, it's putting a HELL of a strain on the bearings,
and on the wood where the centers fasten it to the lathe.

Finally, I have learned NOT to start roughing the wood from the side, where
each corner is whacking the chisel 7 times a second. I go at the tail
end--I think that was Darrell F.'s suggestion on his web site. Two
reasons--first I'm standing out of the throw zone, and second the wood near
the center is moving MUCH slower. I start my cut there, and work my way
slowly out towards the edge. That way I've always got a surface (maybe not
a continuous one, but a surface where I'm cutting) that supports the chisel
when it's cutting the wood. Small bites, sharp chisel, and it really goes
well.

And, I have learned to hold the chisel lightly, and anchor it to the tool
rest, so that if the lathe and the work do vibrate a bit, the chisel is
moving right along with the wood, so the cut stays smooth and the chisel
doesn't gouge into the wood and catch. It doesn't take long to turn away
the eccentric spots and get a smoothly running blank.

Sorry to go on for so long, but I'm rather pleased with how easily I do it
now, compared with the high pucker factor turning I was doing earlier.

Old Guy




"Joe" wrote in message
. net...
Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do
you use? I have a Jet 1442 (reeves) and if it means i can't safely turn a
piece on its lowest speed, I'll have to make a design change.

I know there are many factors to consider here, including balance of the
piece being turned, I'm just looking to see if my lathe's low end is in
the neighborhood.


Thanks,

jc

"Old guy" wrote in message
news9HUi.173728$Fc.60675@attbi_s21...
Finally, I have learned NOT to start roughing the wood from the side,
where each corner is whacking the chisel 7 times a second. I go at the
tail end--I think that was Darrell F.'s suggestion on his web site. Two
reasons--first I'm standing out of the throw zone, and second the wood
near the center is moving MUCH slower. I start my cut there, and work my
way slowly out towards the edge. That way I've always got a surface
(maybe not a continuous one, but a surface where I'm cutting) that
supports the chisel when it's cutting the wood. Small bites, sharp
chisel, and it really goes well.

And, I have learned to hold the chisel lightly, and anchor it to the tool
rest, so that if the lathe and the work do vibrate a bit, the chisel is
moving right along with the wood, so the cut stays smooth and the chisel
doesn't gouge into the wood and catch. It doesn't take long to turn away
the eccentric spots and get a smoothly running blank.


I think you stop vibration faster if you work out on the edge whittling back
toward center in swinging passes. Remember imbalance counts for a lot more
out there with the greater velocity. Starting in the middle is more likely
to get you an uphill dig or splinter, too.

Once you've got a place to reference the bevel, have at it from center to
rim.

On Sat, 27 Oct 2007 15:13:16 GMT, "George" wrote:

I think you stop vibration faster if you work out on the edge whittling back
toward center in swinging passes. Remember imbalance counts for a lot more
out there with the greater velocity. Starting in the middle is more likely
to get you an uphill dig or splinter, too.

Once you've got a place to reference the bevel, have at it from center to
rim.

I rough out bowls as Old Guy suggested, but not to fix imbalance...

As Bill G. points out in his bowl turning DVD, once you have the face (tail
stock end) trued, why beat yourself and the tools up trying to true up the
sides... you're shaping a bowl bottom anyway, so creep up on the rough parts
from the end...

It works for me... I used to round stuff from the sides before I learned this
and it's a lot more work and requires a lot more patience/light cuts to avoid
that damn "thunking" that we all got as beginners.. ;-]


mac

Please remove splinters before emailing

"mac davis" wrote in message
news
On Sat, 27 Oct 2007 15:13:16 GMT, "George" wrote:

I think you stop vibration faster if you work out on the edge whittling
back
toward center in swinging passes. Remember imbalance counts for a lot
more
out there with the greater velocity. Starting in the middle is more
likely
to get you an uphill dig or splinter, too.

Once you've got a place to reference the bevel, have at it from center to
rim.

I rough out bowls as Old Guy suggested, but not to fix imbalance...

As Bill G. points out in his bowl turning DVD, once you have the face
(tail
stock end) trued, why beat yourself and the tools up trying to true up the
sides... you're shaping a bowl bottom anyway, so creep up on the rough
parts
from the end...

It works for me... I used to round stuff from the sides before I learned
this
and it's a lot more work and requires a lot more patience/light cuts to
avoid
that damn "thunking" that we all got as beginners.. ;-]


The old boys did the pivot sweep because they could cut only in one
direction on their pole lathes, but it's still the best way to go,
regardless the current or former DVD. No "beating" at all, because you
control your bite with a firm pivot point, cut downhill, and improve your
surface and stability for the following cut with every scoop. Sure does
balance things faster, too. That's straight science, which is, of course
trumped by any "famous" opinion....

I don't true the bottom until I'm ready to make the recess, there being no
point in it from a stability standpoint, and the area being occupied by the
tailstock anyway.

On Thu, 25 Oct 2007 14:21:45 GMT, "Joe" wrote:

Is there are formula or rough correlation for a starting (roughing down)
speed as it relates to the diameter of the piece being turned? What do you
use? I have a Jet 1442 (reeves) and if it means i can't safely turn a piece
on its lowest speed, I'll have to make a design change.

I know there are many factors to consider here, including balance of the
piece being turned, I'm just looking to see if my lathe's low end is in the
neighborhood.

If it's anything like my Delta gap-bed with the reeves drive, you
should be able to go plenty slow with it. (my low end is about 300
RPM)

In actuality, I've found that I prefer to rough pieces as fast as I
can, just short of a speed that will cause the lathe to walk around on
me. There *is* a reason for that- the faster the high spots are
going, the less likely your tool is to ride in to the low spots and
catch. I'm aware of the contrary arguments, of course- that's just
what works for me.

Especially when you're working with a hollow spindle between tapers, I
wouldn't get too concerned about it. You only have a max 14" swing,
and it's supported on both sides.

My opinion, of course- do what feels safe to you.