A Jarno taper is similar to a MT taper except a different angle. Its not a thread. They make reamers for most tapers and you can check it will a ball drop.

Sorry link is dead... I post that 7 years ago and i lost that .pdf file.

If you are doing a 5-axis toolpath then the backplot rotary axis option does not affect the g-code at all. It only affects the backplot function when the backplot feature called "simulate rotary axis" is enabled. If you doing a 4-axis toolpath, you'll see that the word "backplot" dissappears from the name of that command; in 4-axis mode this feature definately can affect the g-code output and may determine whether you have A, B or C axis calls in your 4-axis toolpath.

So I was about to merge some geometry from one program to another and for the hell of it tried to change my level to 0 to avoid geometry getting mixed up together on level 1. It briefly showed level 0 on my level manager screen with the level name, but when I looked back again later it had changed to level 1 and the name had disappeared. geometry could still be seen on the screen but was now un-selectable. I had already saved it so I decided to reopen the .mcam file and now no geometry was visible. I know if you hover over the level # area it shows yellow saying "1 to 200000" but if you change the number in the upper portion of the manager it will allow you to change it to 0 or at least my system did. Just letting you guys know or curious if any of you have ever done the same thing.

Lol thanks Colin. 2 back ups cause he Knows things about us.. lol