Hollow Form Opening: What size hole??

[Bill Wilcox]

Hello All,
I am in the final stages of my fabrication of a "Homemade Jamison Hollowing System". I plan on turning some round hollow forms as well as vase's and urns. My final part in the fabrication is figuring out the size of the cutter holder for the JHS as well the bolt size to hold the cutter on the 3/8" drill rod shaft that goes into the boring bar. Any help would be greatly appreciated.
Also, with these round "David Ellsworth style and with other types of hollow forms. What would be the usual hole size to first drill to begin the hollowing process.
I really enjoy this site and it has given me a wealth of information and creative ideas for things to work on.

BTW. If anyone remembers the Black Walnut wood gloat I posted earlier this Spring, I received a call from the gentleman who had the BW and tells me that he is getting ready to cut some Hard Maple, Sugar Maple, Honey Locust and some other types I can't remember plus some stumps from all of these trees. The Maple and the HL are all 14-16 in dia. 8-10 feet long. He said he will get them cut sealed and placed in the same area as he did the BW. He is just happy to know that this wood is going to a wood turner.

[Michael James]

Wish I could do metal work / fabrication....but no exp at all there.
I just wanted to tell you that Ellsworth, in his video, says "if you're new to HF's do your self a favor and make the hole big enough to work with and then work your way down as your skill level increases..." paraprasing, but close. I don't know how much of a difference a captured rig would make or your experience level. Maybe try a test piece before you drill that special piece!
my .02 cents,
mj

[Mike Cross]

Do you have any progress pictures of your project? We all like to see pictures. Sorry I can't help you with your question on the bolt size though.

Mike