"Mike Burr" wrote in message
...
Owen Lowe wrote:

Howdy All,

Since things appear a little slow here - maybe folks are distracted by
the coming holiday weekend - Let's be safe out there - don't M-80 any
fingers or poke your eye out with a sparkler as you'll need those for
turning - otherwise hope all have a sunny, pleasant 4th!

Awhile back I looked into messages about turning bone and even messaged
a tad with Arch- as I recall - about the characteristics and qualities
of bone as a turning material. My project was turing a small ring that
would become an insert in a candlestick. This is what I encountered:

Finding bone: To make the rings, I needed bone that had a predetermined
outside diameter with enough wall thickness to true it to the proper
outside and inside diameters. That turned into a challenging task. I
looked at many places, including my grocery store for "raw" bones and
the pet and feed stores for the dog chew bones. I found the best course
was to paw through the bins at a couple Petsmarts for the bleached,
non-filled bones. These are clean and white with no need to do any
boiling, scraping or bleaching. Try to pick out the bones with the
thickest walls and accept the reality that both the roundness of the
shape and the thickness generally changes from one end of the 4"ish
bones to the other. Buy a couple since you really don't know if the bone
has the proper dimensions for the length you need until you cut it
apart. Cost was $3.00 each.

Prepping the bone: To make the required rings, I elected to bandsaw
disks off the length so I could use a glue block on the lathe to begin
the shaping. The bone cut easily using my standard 3-tooth blade - I
tried a finer 6 or 10 tooth but the gullets seemed to fill with the bone
powder. The smell is pretty easily ID'd if you have ever had a tooth
drilled - smells just like it to me. Sawing it is a dusty process but
goes easily.

Gluing: The bone glued easily and securely to both the glue block and
into the candlestick using CA and epoxy, respectively.

Lathe Turning: I found that shaping proceeded more smoothly with a
scraping action rather than cutting. This could be a matter of the size
and shape I was turning since I didn't have a more spindle orientation
to really try a gouge. It is a dusty process and the dust will collect
onto and into the chuck recesses. A dusting with a brush or air is
needed once you complete the turning. I believe the bone has a more
abrasive action on the tool edge than a dense wood, like African
Blackwood or other tropicals, does. Perhaps it's just a matter of
hardness or it might be an factor of the calcium or whatever. Frequent
touchups of the edge is required or the bone won't respond to shaping
very kindly. It seemed to me that the speeds that yielded the best
shaping results were on the lower end of the spectrum - in the 500-1200
rpm range. Given that my lathe's lowest speed is 500 rpm I can't speak
to speeds slower than that.

Sanding: Bone sands easily and beautifully - this is where bone's appeal
as a component in a turning will become evident. I started with 220,
then 320 and worked up to 4000 using Mirka's Abralon from 500 and up.
Once you get to the 1000 and higher you will see the polish develop and
the surface begins to look like ivory. Just beautiful.

Finishes: The finish I used was Behlen's Rockhard varnish applied to the
entire turning once it was assembled. The bone seemed to accept it just
fine and didn't change in appearance much, if any. Though I didn't use
any other finish, I don't see why the bone would be affected negatively
by whatever you use. As to leaving it unfinished, it appears to dull
just a little over time. If it's a piece that's frequently handled I
believe the white will soften to an ivory color. (I have an old bone
burnisher/letter creaser (whatever it's called) on my desk that came
from my grandparent's desk - it has a beautiful, smooth, light-ivory
colored surface.)

For more info and visuals on bone and other non-wood materials for
turning, look into Bonnie Klein's "Turning Unusual Materials" video.




Thanks for some more insight. I finished turning a pen from a young
deer antler and found the smell very reminiscent of the dentists
office. However I was wondering, does the time of season make a
difference in the core density and wall thinknes?

yes, deer 'drop' their antlers, and they are at their max density/hardness
then
antlers, unlike horns are the same material as bone

if you can get some Indian Stag hornactually an antler
it tends to be denser and whiter than domestic ones, ion my experience

HTH
Otto

Michael.