Dumb Lathe Question...
 

I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

Thanks for any answers.

Rich.....

Dumb Lathe Question...
 

"rich" wrote in message
ups.com...
I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

You can!
I a duplicator unit that essentially does that; it has a guide that follows
a template and a cutter much like that used on metal lathe.

But, and I hope I don't sound goofy, doing it that way isn't much different
than buying it; since it takes no skill, there is no enjoyment in doing it.
Maybe that's not important to you, but it is 90% of why I do woodworking.

Dumb Lathe Question...
 

"rich" writes:

I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

You could for cylinders. It's hard to use the metal lathe to cut
curves (o.e. bowls). There are toolrests (for the 7x12) and you can
get a ball turning attachment for a metal lathe. But this takes longer
than freehand.



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Dumb Lathe Question...
 

Another answer is that when you are cutting metal, you are essentially doing
a scraping cut. A scraping cut on wood, especially on spindles requires a
LOT of sanding to make presentable.

To get a good wood finish, you have to do a shear (slicing) cut, which I
don't think is programmable.

That being said I visited a manufacturer of oboes who turned the very
intricate and precise inside of his wood oboes using a metal cutting lathe
with a power feed.

Old Guy


"rich" wrote in message
ups.com...
I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

Thanks for any answers.

Rich.....

Dumb Lathe Question...
 

"rich" wrote in message
ups.com...
I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

You could, but that would be solving a non-problem.

You misunderstand how "freehand" is done. Lateral reference lines at
measured from the end of a spindle to mark the begining, end or middle of a
shape. Those reference lines are then cut to a reference depth. From there,
it is a simple matter of connecting the dots.

That's how you make four matching table legs "freehand". It is no more
"freehand" than a child's "connect the dots" drawing.

Regards,

Steve

Dumb Lathe Question...
 

Since when? I've been turning metal professionaly for 20 years. The only
time I ever use a scraping cut is for large form tools. In other words,
seldom.

"Old guy" wrote in message
news:GNKdh.1089004$084.511539@attbi_s22...
Another answer is that when you are cutting metal, you are essentially
doing
a scraping cut.

Dumb Lathe Question...
 

Duplicators work fine. BUT... they essentially scrape the wood, not
cut it. No razor sharp cuts when using a wood lathe duplicator. The
tear out from these things can be just gawdawful since you are dragging
that bit along the profile template.

Making four parts that are exactly the same isn't as easy as connecting
dots for me or the others in my club. In fact, one of our challenges
was to make fancy, profiled, candle sticks as close to each other in
dimension as we could. Two wasn't bad. No one got to four.

But on table legs, that would be different. It is plain spindle
turning, and you could put witness marks and depth cuts as needed. It
IS similar to connecting the dots in that respect. But the good news
is this: If you are off a little, who will know? On our candlesticks
we set all of them next to each other and got out calipers to check.
YOUR legs will be on four different side of a table.

And if you cut them with a normal gouge, you cut way down (maybe
eliminate) tearout and cut down on your sanding. Plus, you're not in
for a few hundred dollars for a good duplicating attachment. And it is
more fun.

Robert

Dumb Lathe Question...
 

On 6 Dec 2006 17:15:47 -0800, "rich" wrote:

I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

Thanks for any answers.

Rich.....


Metal-cutting tools are slower than wood-cutting tools. It is
possible you can use a metal lathe, but the holders, jaws, etc are
different.

Dumb Lathe Question...
 

Speed range on most metal lathes is generally from 50 to 1500 RPM. which is
generaly too slow for wood turning. I have known people to profile cut
cabinet knobs on a metal lathe with success using hard tight grained timbers
with no sanding required but thats about a metal lathes limit. For general
turning you require a slicing motion. Although it would be possible to set
up a chisel in the tool holder to slice for turning cylinders it would be
much slower than turning them by hand on a wood lathe. It would not be quite
as good a result 'off the chisel' as you could not 'fine tune' the cutting
angle for a bit of difficult grain.

"rich" wrote in message
ups.com...
I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

Thanks for any answers.

Rich.....

Dumb Lathe Question...
 

"Old guy" writes:

Another answer is that when you are cutting metal, you are essentially doing
a scraping cut. A scraping cut on wood, especially on spindles requires a
LOT of sanding to make presentable.

AFAIK - The Oland tool and a metal lathe bit is essentially the same, right?


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Dumb Lathe Question...
 

"Paul D" wrote in message
...
Speed range on most metal lathes is generally from 50 to 1500 RPM. which
is
generaly too slow for wood turning.

Nope. Takes the same effort to sever the fibers regardless the speed.
Makes anything above that mere convenience mixed with danger. It's that MV
squared thing. Use your tool properly and 1500 is all you'll ever need. And
that's for buffing.

Dumb Lathe Question...
 

"Bruce Barnett" wrote in message
...
"Old guy" writes:

Another answer is that when you are cutting metal, you are essentially
doing
a scraping cut. A scraping cut on wood, especially on spindles requires
a
LOT of sanding to make presentable.

AFAIK - The Oland tool and a metal lathe bit is essentially the same,
right?

The nose of a gouge can be used to scrape, too. The Oland looks like a
tooling bit, but the turner often uses the edge to shear rather than scrape.
Darrell Feltmate is one of the internet-available advocates as you know.
http://www.aroundthewoods.com/ Problem is that without rigid tool hold and
a bevel, things can roll or jump and get away quickly.

Other people shear with their gouges, which gets the bevel into play to
steady everything, like this guy.
http://s108.photobucket.com/albums/n...erryPeelIn.flv

Dumb Lathe Question...
 

rich wrote:
I don't have a lathe, and am not sure if I need one yet, and have
never used a wood lathe. 35 years ago, I did some work on a metal
lathe in a research lab. Here's the dumb question: Why wouldn't I
use a metal lathe for wood so I could produce identical cylindars,
etc using the screw feeds rather than try and "freehand" the parts
and hope they are the same size?

Thanks for any answers.

Rich.....

Metal lathes arean't really very good for woodworking. Speeds are wrong,
knives are different, etc.. Unless you have money for a lot of tooling,
they're harder to use because of the differences between things made of
metal and of wood. IFF a metal lathe worked for wood, it'd also be slower
and cut rougher in wood.

There ARE some that would work, but they're generally pretty pricey. OH,
and more comples to operate and maintain properly.

Pop`

Dumb Lathe Question...
 

Thanks for all the input! Gonna have to give this some thought.

I can see where the speed might be a factor, but I think you could
grind a tool bit to slice with a little care and design. I agree that
inside cuts on a bowl would be tough on a metal lathe, but I'm not
fully convinced outside cuts couldn't be done.

As to the artistry of it all, i presently enjoy a dove tail jig for the
router, but also enjoy doing them with a saw and chisel. Both have
their uses. I can see the art and skill with a wood lathe and a bowl,
but also the repeatability and precision of a metal lathe.

Oh, well.... Guess I'll make some more saw dust.

Thanks to all,

Rich.....


Pop` wrote:
rich wrote:
I don't have a lathe, and am not sure if I need one yet, and have
never used a wood lathe. 35 years ago, I did some work on a metal
lathe in a research lab. Here's the dumb question: Why wouldn't I
use a metal lathe for wood so I could produce identical cylindars,
etc using the screw feeds rather than try and "freehand" the parts
and hope they are the same size?

Thanks for any answers.

Rich.....

Metal lathes arean't really very good for woodworking. Speeds are wrong,
knives are different, etc.. Unless you have money for a lot of tooling,
they're harder to use because of the differences between things made of
metal and of wood. IFF a metal lathe worked for wood, it'd also be slower
and cut rougher in wood.

There ARE some that would work, but they're generally pretty pricey. OH,
and more comples to operate and maintain properly.

Pop`

Dumb Lathe Question...
 

In that they are both made of steel, yes.

"Bruce Barnett" wrote in message
...
AFAIK - The Oland tool and a metal lathe bit is essentially the same,
right?

Dumb Lathe Question...
 

The metal lathe I have in the garage will do 3000 rpm. The two (manual)
lathes at work will do 2000 rpm, the CNC will do 4000. The Delta 12"
variable speed wood lathe tops out at 2000 rpm.

"Phisherman" wrote in message
...
On 6 Dec 2006 17:15:47 -0800, "rich" wrote:


Metal-cutting tools are slower than wood-cutting tools. It is
possible you can use a metal lathe, but the holders, jaws, etc are
different.

Dumb Lathe Question...
 

No.

"Paul D" wrote in message
...
Speed range on most metal lathes is generally from 50 to 1500 RPM. which
is
generaly too slow for wood turning. I have known people to profile cut
cabinet knobs on a metal lathe with success using hard tight grained
timbers
with no sanding required but thats about a metal lathes limit. For general
turning you require a slicing motion. Although it would be possible to set
up a chisel in the tool holder to slice for turning cylinders it would be
much slower than turning them by hand on a wood lathe. It would not be
quite
as good a result 'off the chisel' as you could not 'fine tune' the cutting
angle for a bit of difficult grain.

"rich" wrote in message
ups.com...
I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

Thanks for any answers.

Rich.....

Dumb Lathe Question...
 

Yes.

"George" wrote in message
. ..

"Paul D" wrote in message
...
Speed range on most metal lathes is generally from 50 to 1500 RPM. which
is
generaly too slow for wood turning.

Nope. Takes the same effort to sever the fibers regardless the speed.
Makes anything above that mere convenience mixed with danger. It's that
MV
squared thing. Use your tool properly and 1500 is all you'll ever need.
And
that's for buffing.

Dumb Lathe Question...
 

No.

"Pop`" wrote in message
news:H6Xdh.155$9h.128@trnddc05...

Metal lathes arean't really very good for woodworking. Speeds are wrong,
knives are different, etc.. Unless you have money for a lot of tooling,
they're harder to use because of the differences between things made of
metal and of wood. IFF a metal lathe worked for wood, it'd also be slower
and cut rougher in wood.

There ARE some that would work, but they're generally pretty pricey. OH,
and more comples to operate and maintain properly.

Pop`

Dumb Lathe Question...
 

I've machined steel, aluminum, plastic, phenolic, fiberglass, and wood on a
metal lathe. All with good results.

"rich" wrote in message
oups.com...
Thanks for all the input! Gonna have to give this some thought.

I can see where the speed might be a factor, but I think you could
grind a tool bit to slice with a little care and design. I agree that
inside cuts on a bowl would be tough on a metal lathe, but I'm not
fully convinced outside cuts couldn't be done.

As to the artistry of it all, i presently enjoy a dove tail jig for the
router, but also enjoy doing them with a saw and chisel. Both have
their uses. I can see the art and skill with a wood lathe and a bowl,
but also the repeatability and precision of a metal lathe.

Oh, well.... Guess I'll make some more saw dust.

Dumb Lathe Question...
 

"CW" wrote in
ink.net:

No.


If you're going to reply with a one word answer, at least provide some
context, please! Are you saying that the whole post was bad, or just a
paragraph was disagreeable?

Unresolved Ambiguity
--
Wise is the man who attempts to answer his question before asking it.

To email me directly, send a message to puckdropper (at) fastmail.fm

Dumb Lathe Question...
 

CW wrote:

Since when? I've been turning metal professionaly for 20 years. The only
time I ever use a scraping cut is for large form tools.

Since you stuck a tool ground for metal turning into a piece of wood.
Change the grind angles and it's not so bad.

You'll also find few metal-turning lathes with high enough speeds to be
ideal for spindle turning, and those that do have them generally don't
appreciate a coating of damp woodshavings.

I don't turn wood on a metal turning lathe, except occasionally using
one for boring.
http://quercus.livejournal.com/122184.html
I do turn metal by hand on a wood lathe though, or at least brass. If
you're doing Victorian repro it's the easiest way to get the flowing
curves on some parts --- the originals would have been hand-rutned too.

Dumb Lathe Question...
 

"Old guy" writes:
Another answer is that when you are cutting metal, you are
essentially doing a scraping cut. A scraping cut on wood,
especially on spindles requires a LOT of sanding to make
presentable.

"Bruce Barnett" says
AFAIK - The Oland tool and a metal lathe bit is essentially the same,
right?

"CW" writes:
In that they are both made of steel, yes.

It's more than that. I'm talking about the tool described here

http://www.aroundthewoods.com/oland.shtml

To quote Darrell,

"The tip is a 1/4" x 2 1/2" HSS cutting tool, standard in the
metal lathe industry."

I can take the same exact bit with the same profile and use it in
Darrell's tool, Then I can move it to a metal lathe. The bit doesn't change.

"Old guy" says it's a scraping cut in a metal lathe.
It should also be a scraping cut in a wood lathe as well, right?


So I guess the question is

Is the Oland tool a scraping cut?
Do all scraping cuts require a lot of sanding afterwards?

As Darrell says

"Some people object to the Oland tool because it looks like a scraper
and they want to make shaving"


To be precise, Darrell says the Oland tool should be used with the
bevel rubbing (for support I guess). That will change the cutting
angle a little, but it still looks like a scraping cut to me. One
could eassly add a negative rake to get the exact cutting angle as the
Oland with the bevel against the wood.



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Sending unsolicited commercial e-mail to this account incurs a fee of
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Dumb Lathe Question...
 

"CW" writes:

No.

Thank's for the answer. What was the question?
Frankly - I have no idea which part of the message you are responding to.





"Paul D" wrote in message
...
Speed range on most metal lathes is generally from 50 to 1500 RPM. which
is
generaly too slow for wood turning. I have known people to profile cut
cabinet knobs on a metal lathe with success using hard tight grained
timbers
with no sanding required but thats about a metal lathes limit. For general
turning you require a slicing motion. Although it would be possible to set
up a chisel in the tool holder to slice for turning cylinders it would be
much slower than turning them by hand on a wood lathe. It would not be
quite
as good a result 'off the chisel' as you could not 'fine tune' the cutting
angle for a bit of difficult grain.

"rich" wrote in message
ups.com...
I don't have a lathe, and am not sure if I need one yet, and have never
used a wood lathe. 35 years ago, I did some work on a metal lathe in a
research lab. Here's the dumb question: Why wouldn't I use a metal
lathe for wood so I could produce identical cylindars, etc using the
screw feeds rather than try and "freehand" the parts and hope they are
the same size?

Thanks for any answers.

Rich.....






--
Sending unsolicited commercial e-mail to this account incurs a fee of
$500 per message, and acknowledges the legality of this contract.

Dumb Lathe Question...
 

"George" wrote in message
. ..

"Paul D" wrote in message
...
Speed range on most metal lathes is generally from 50 to 1500 RPM. which
is
generaly too slow for wood turning.

Nope. Takes the same effort to sever the fibers regardless the speed.
Makes anything above that mere convenience mixed with danger. It's that
MV
squared thing. Use your tool properly and 1500 is all you'll ever need.
And
that's for buffing.


Speed as little to do with effort required to sever fibres. That come down
to torque which will change with speed changes and actually becomes less
torque at higher speeds. Speed only relates to being able to do a cleaner
cut while working at a faster pace. I rarely turn spindles below 1400rpm. As
a general rule the only time I turn below 1400 is for roughing down square
stock, spindles larger than about 4" Dia.or on long slender spindles to cut
down on whip. Use your tool properly and there is no increase in danger at
higher speeds. Naturaly enough if you are doing something that is a little
bit 'tricky' or difficult turn at lower speeds. As a metal lathe has a
greater selection of speeds (typically 9 - 15 speeds) than a wood lathe
(typically 5 speeds) it would be more useful for larger faceplate work but
the bulk of a metal lathe makes access a little more restrictive.

Dumb Lathe Question...
 

"Paul D" wrote in message
...

Speed only relates to being able to do a cleaner
cut while working at a faster pace.

Faster, perhaps. Cleaner, hardly. My carving gouges make exceptional cuts
at zero RPM. Ol' Roy demonstrates the proper cuts by rotating by hand as
well.

Use your tool properly and there is no increase in danger at
higher speeds.

Newton disagrees. Potential energy of a departing fragment or the piece
itself is proportional to the square of velocity. If it never happens,
dandy, but use your tool properly and you don't need to take the risk.

Dumb Lathe Question...
 

"George" wrote in message
...

"Paul D" wrote in message
...

Speed only relates to being able to do a cleaner
cut while working at a faster pace.

That should have read "clean cut at faster pace"


Faster, perhaps. Cleaner, hardly. My carving gouges make exceptional
cuts
at zero RPM. Ol' Roy demonstrates the proper cuts by rotating by hand as
well.

Use your tool properly and there is no increase in danger at
higher speeds.

Newton disagrees. Potential energy of a departing fragment or the piece
itself is proportional to the square of velocity. If it never happens,
dandy, but use your tool properly and you don't need to take the risk.