In article , JR Johnson
wrote:

Guys, I am building a coring lathe to cut bowl cores from half a log
section. That's right, I am primarily a wood turner, but I built both my
lathes from scratch, so I am somewhat metal capable.

The coring lathe will take a log half section and secure it with a
faceplate. Then the largest coring cutter that will fit the log half will
pivot into the faceplate side of the log and cut the corners, etc. away,
leaving the outside of the largest bowl. Then the next coring cutter will
pivot into the log half and remove the largest bowl. And so on down to the
smallest bowl.

To support the cutters, I need perfect (essentially, plus/minus 0.0625 would
be ok) spherical sections. In a perfect world, the largest section would
have a 12" inside radius, the next a 10.5" radius, the next a 9.0" radius,
then an 7.5", 6.0", 4.5" and finally an 3.25" radius. Wall thickness
needs to be 0.250".

I could do without the smallest radius cutter, if necessary, as it makes the
smallest (and less valuable) bowl.

Imagine an orange, with the peeling sliced top to bottom say, 8 times. Take
one half of the peeling and that is what the cutter will look like.

Anyone have any ideas as to an economical (scrapyard prices preferred)
source for such items?

Best regards,
James Johnson

Please reply directly to me.




Any decent metal spinning shop can make them for you, but the spinning
forms will be pricey.