Double Start Thread
Not sure when done last but hope I get it right?
On some machines there is a easy way to turn a gear, especially good for more starts like 3 or 4 but moving the tool with compound works too.
Lets assume.... when looking at the bolt [thread] and checking with the thread gauge for pitch and it will show
"8"...8 threads per inch, .125 pitch, this is half, so you are actually cutting 4 threads per inch, when done, move the tool over on your compound by .125" to be between the thread you have cut and start cutting second thread.
Konrad