• We just finished a major forum upgrade. Please check out the "Whats New and Help" Thread at https://aawforum.org/community/index.php?threads/forum-upgrade-whats-new-and-help-march-2021.17436/ If you are having problems using the forums, please clear your browser cache and that should clear up any issues. Otherwise post in the Help Thread or email us at forum_moderator@aawforum.org. Hope you enjoy the refreshed site!
  • 3/30/21 - We finished what was hopefully the last part of the forum upgrade we started earlier this month, the rebuilding of all of the permissions. In our testing everything seems to be working correctly but if you have any problems please post in the "Forum Technical Support" forum and we will take a look at it. You will also see a few changes with the main forum index. We have moved the AAW Member Forums to their own group and the Marketplace Forums to their own group. This simplified the permissions configuration for the forums and hopefully it will make the forums a little easier to naviagate. Thanks!
  • Gallery Images: Title and Description Required

    Please read the new sticky announcement HERE for full details.

  • Welcome new registering member. Your username must be your real First and Last name (for example: John Doe). "Screen names" and "handles" are not allowed and your registration will be deleted if you don't use your real name. Also, do not use all caps nor all lower case.

Green Goblet Turning

Joined
Jul 19, 2018
Messages
828
Likes
619
Location
Ponsford, MN
This is a technique that I was initially introduced to at a Demo by Del Stubs in about 1990 and I am guessing that I have turned well over 1000 goblet forms ranging in size from about 2" tall by 1 1/2" diameter to 18" tall by 10" diameter. The goblets are turned from the full round of a tree trunk or branch and it is best using fresh cut live trees cut in the dormant stage, which is the best way to guarantee that the bark will stay on. The reference to shear scraping is as it was at the time, which I still believe is the best and most efficient way to get a smooth finish on green wood. The picture below will show how out of practice I am in this case the wood is an upper branch of an Iron Wood or American Hornbeam cut down on Sunday the 4th of April. The problem is the heart wood is very dry and darker than the sap wood so very little light came through at the transition so when I got down to about 10thou" it fell off as shown. The 3rd one has a knot that caused a problem. The 4th one I sprayed water plus stopped regularly the measure the thickness so I knew what the light getting through meant.
DSC00886.JPG

The photo below is the first one when things were going according to plan, the thickness at the bark is about 60thou" and down to 20thou"at about 1/8" before the point of separation.
PXL_20210406_221544330.jpg
 

Attachments

  • GreenGobletturning2020.pdf
    340.8 KB · Views: 24
Joined
Jan 13, 2021
Messages
65
Likes
26
Location
San Antonio, TX
Yes thank you Don,
Great pdf and your photos really provide a fantastic introduction to someone like myself who has not seen these types of turnings.
 
Joined
Jul 19, 2018
Messages
828
Likes
619
Location
Ponsford, MN
Thanks for the interest and if you have any specific questions I would be glad to try to answer.

One of the main reasons I posted this is the recent infatuation with the so called NRS, which I think is an inferior application of the burred scraper but is easier to teach. The burred scrapers used in the turning of these thin walled goblets is mostly applying the burr at a negative rake shearing angle whether it is inside or outside. The NRS per accepted dogma is used flat on the tool rest, which is cutting at 90 degrees to the wood grain where as if you rotate the tool to between 45 and 60 Degrees it will make a shearing cut that would be an advantage in an area like the concave lip of the goblet.
 
Joined
Jan 13, 2021
Messages
65
Likes
26
Location
San Antonio, TX
I've just rounded the bottom edges on my scrapers using my 80# CBN wheel today. I've found that I've been rotating the scrapers and that the sharp edges were marking up my rest and even starting to put slight grooves into it. I started rotating the scrapers on the last few bowls I've turned trying to find that sweet spot. Its very reaffirming to read your last reply Don.
Al
 
Joined
Jul 19, 2018
Messages
828
Likes
619
Location
Ponsford, MN
I've just rounded the bottom edges on my scrapers using my 80# CBN wheel today. I've found that I've been rotating the scrapers and that the sharp edges were marking up my rest and even starting to put slight grooves into it. I started rotating the scrapers on the last few bowls I've turned trying to find that sweet spot. Its very reaffirming to read your last reply Don.
Al
Been there don that. Those sharpe corners definitely can cut into the tool rest especially a cast iron rest.
 
Top