Thanks for the welcomes.
Going to try and add some photos of what I am doing. The taper I am getting is at the open end so my 4" cap is 4.020" at the opening. To compensate for the size we turned the aluminum mandrel smaller by .020". The open end comes out to 4.00" but it has this taper, which I don't care for. Being a bit of a perfectionist I would like to, if possible, totally eliminate or reduce this taper considerably.
Here's the setup I have. Tried spinning at 312, 558 & 765 rpm but didn't find much difference in the performance, not that I noticed anyway.
The 3 sizes I'm working on at present are 4.00", 6.00" & 8.00" O.D. all with a 1/2" long skirt.
