My 'g-coding' is coming along nicely.On many compound moves that also contain an 'a-axis' move ,I get reasonable velocity.I was under the impression that I could do a g01 'a'-n alone and could get the speed up...but that doesn't happen even with a rather large 'F'.So I went back to a little test code that Brian showed me to check repeatability on the a-axis.His code just said: 'a'-n(no G-anything)alone on a 'block'; and the axis screams(in a good way) and bingo,right on the money in terms of repeatability.Is saying just : 'a'-n equivalent to a G0 for this axis?

IIRC,

  Most G codes are modal. When you call one, it remains active until another cancels it out. Ie, G90 cancels out a G91 (abs, inc)
So, the code you have might have a G0 further up the line, making it feasible to just call out A0.

Ah yes,you are so correct.Thanks,I'm getting there

I'm like a blind mouse...Every once in a while, the blind mouse gets the cheese.