Boring head used as a ball-turning tool


I'm "stealing" this from a "newsletter" I got.

Wow !!! Seems too simple, but I'm going to give it a try. Last time
I wanted to use one of the two true "ball-turners" I have, it was for
a small ball on a short piece of material, and I couldn't get close
enough to do it without being up against the chuck or even a 5C
collett. I had to resort to Guy Lautard's "step over" method and
finish with a file. I think this idea might just work for that job
next time.


http://www.homemodelenginemachinist.com/f28/boring-head-ball-radius-turner-23019/

Absolutely brilliant!!


--

"
I was once told by a “gun safety” advocate back in the Nineties
that he favored total civilian firearms confiscation.
Only the military and police should have weapons he averred and what did I think about that?

I began to give him a reasoned answer and he
cut me off with an abrupt, “Give me the short answer.”

I thought for a moment and said, “If you try to take our firearms we will kill you.”"

Gunner Asch fired this volley in
:

http://www.homemodelenginemachinist....all-radius-tur
ner-23019/

Hey! That really is smart! I sold my Holdridge tool set, because I so
seldom do balls -- but I still do need to occasionally.

I have a boring head that will satisfy 99% of all the balls I need to turn!

Lloyd

On Tue, 13 May 2014 14:17:57 -0700, Gunner Asch
wrote:



Boring head used as a ball-turning tool


I'm "stealing" this from a "newsletter" I got.

Wow !!! Seems too simple, but I'm going to give it a try. Last time
I wanted to use one of the two true "ball-turners" I have, it was for
a small ball on a short piece of material, and I couldn't get close
enough to do it without being up against the chuck or even a 5C
collett. I had to resort to Guy Lautard's "step over" method and
finish with a file. I think this idea might just work for that job
next time.


http://www.homemodelenginemachinist.com/f28/boring-head-ball-radius-turner-23019/

Absolutely brilliant!!
AND ON TOPIC!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


--
Unka' George

"Gold is the money of kings,
silver is the money of gentlemen,
barter is the money of peasants,
but debt is the money of slaves"

-Norm Franz, "Money and Wealth in the New Millenium"

http://s1242.photobucket.com/user/Ka...g.html?filters[user]=129196763&filters[recent]=1&sort=1&o=1
http://s1242.photobucket.com/user/Ka...g.html?filters[user]=129196763&filters[recent]=1&sort=1&o=1


Here's my solution. Even simpler IMHO.

Its just a tool holder mounted mounted on the centerline of the
compound. Slightly loosen the compound and put a 1/2" extension in the
toolholder to rotate. Both convex and concave radii can be accurately
turned by adjusting the compound lead screw.

Karl

Karl Townsend fired this volley in
:


Its just a tool holder mounted mounted on the centerline of the
compound. Slightly loosen the compound and put a 1/2" extension in the
toolholder to rotate. Both convex and concave radii can be accurately
turned by adjusting the compound lead screw.

'Totally limited in radius to the effective radius of the tool holder slot.
To make any bigger balls, you'd have to build an 'extender' that moved the
tool mounting point off to the side of the toolrest. THAT ain't gonna work
on a standard lantern toolpost machine!

LLoyd

On Tue, 13 May 2014 17:49:25 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Karl Townsend fired this volley in
:


Its just a tool holder mounted mounted on the centerline of the
compound. Slightly loosen the compound and put a 1/2" extension in the
toolholder to rotate. Both convex and concave radii can be accurately
turned by adjusting the compound lead screw.

'Totally limited in radius to the effective radius of the tool holder slot.
To make any bigger balls, you'd have to build an 'extender' that moved the
tool mounting point off to the side of the toolrest. THAT ain't gonna work
on a standard lantern toolpost machine!

LLoyd

Yep, the first thing to hit would be the top of the compound. So,
about a six inch diameter maximum on my 10EE.

Karl

This is incredibly clever, whoever employs that fellow probably enjoys
a great bang for the buck.

i

On 13/05/14 22:17, Gunner Asch wrote:

Boring head used as a ball-turning tool


I'm "stealing" this from a "newsletter" I got.

Wow !!! Seems too simple, but I'm going to give it a try. Last time
I wanted to use one of the two true "ball-turners" I have, it was for
a small ball on a short piece of material, and I couldn't get close
enough to do it without being up against the chuck or even a 5C
collett. I had to resort to Guy Lautard's "step over" method and
finish with a file. I think this idea might just work for that job
next time.


http://www.homemodelenginemachinist.com/f28/boring-head-ball-radius-turner-23019/

Absolutely brilliant!!


--

"
I was once told by a “gun safety” advocate back in the Nineties
that he favored total civilian firearms confiscation.
Only the military and police should have weapons he averred and what did I think about that?

I began to give him a reasoned answer and he
cut me off with an abrupt, “Give me the short answer.”

I thought for a moment and said, “If you try to take our firearms we will kill you.”"
Clever but if you have a mill you can also use the boring head in that
to generate a ball, you do need a rotary table or similar to rotate the
workpiece as the boring head cuts.

"Gunner Asch" wrote in message
...


Boring head used as a ball-turning tool


I'm "stealing" this from a "newsletter" I got.

Wow !!! Seems too simple, but I'm going to give it a try. Last time
I wanted to use one of the two true "ball-turners" I have, it was for
a small ball on a short piece of material, and I couldn't get close
enough to do it without being up against the chuck or even a 5C
collett. I had to resort to Guy Lautard's "step over" method and
finish with a file. I think this idea might just work for that job
next time.


http://www.homemodelenginemachinist.com/f28/boring-head-ball-radius-turner-23019/

Absolutely brilliant!!


That is truly an elegant solution and a clear case where a few pictures are
worth a thousand words.

It took me a while to figure out why this seemed such an enjoyable post.

I was showing someone my Ron Reil burner and forge and it hit me.
This was the first, on topic, informative post I have seen on this forum in
a long time.
It brought back memories of the time when guys like Fitch, Scott Logan,
Teenut, Ernie, Pete Albrecht, and Steve Lindsay were all around and the
metalworking information flowed like wine.

Paul K. Dickman

"Karl Townsend" wrote in message
...

http://s1242.photobucket.com/user/Ka...g.html?filters[user]=129196763&filters[recent]=1&sort=1&o=1
http://s1242.photobucket.com/user/Ka...g.html?filters[user]=129196763&filters[recent]=1&sort=1&o=1


Here's my solution. Even simpler IMHO.

Its just a tool holder mounted mounted on the centerline of the
compound. Slightly loosen the compound and put a 1/2" extension in
the
toolholder to rotate. Both convex and concave radii can be
accurately
turned by adjusting the compound lead screw.

Karl


I cranked the compound all the way back, loosened the swivel clamps
and lightly punch-marked the center of rotation, which is on my
lathe's compound top a little less than an inch forward of the slot.

The center of rotation is easy to find by sticking a paper label over
the likely area and swiveling the compound under a pencil braced
against the chuck, making smaller and smaller concentric arcs.

To turn a small ball I position the punch mark under its intended
center, zero the crossfeed dial, and mount the bit on spacer blocks
with carriage bolts on either side to hold a clamp bar. I set the
radius by measuring from the bit tip to the punch mark with a small
square. I could machine a tool block that fits the slot and holds a
1/4" bit at center height.

Then I replace the pointed rod used for setup with the workpiece, back
off the crossfeed and slowly cut back in to the zero while swinging
the compound. The work can be located axially against the bit.

My old lathe has too much play to swivel really smoothly for a nice
surface finish but it's quicker than forming a ball by steps from a
spreadsheet and filing it, which I did to cut larger balls for a hoist
base from dumbbells.

The step method went faster when I first input large steps to rough
out the sphere, then reduced them to finish it. The step size or Depth
of Cut is the increment between rows. The equation for a circle is X^2
+ Y^2 = (radius)^2.

jsw