trying to cut a worm shaft on 200 matrix II issues

My first post, would appreciate some wisdom that this forum has from reading a while.

Long story short;
I run an old QT15 and the other machine next to me is a newer 200.
The place that I work for needs to manufacture their own worm shaft.
The issue is that when programmed on zero off set of the insert it does fine.
It is a two pass worm gear design program.

After the first run on the part it needs .040" deeper on the worm shaft to achieve the desired over pins measurement for a part to print.

They keep adding the off set into the tool wear offset to get the desired results.

If they take a shaft and add the .040" offset on the first cut it will destroy the insert.

In my thinking, there has to be a way to program it to where the machine will not take an over huge bite into the bar on the first pass, but no one here knows what to set in the program.

I know that I may not be making much sense, but I am a relative newbie running an old QT15 while watching this issue off to the side that needs to be addressed.

Pretty sure you have questions to try and help resolve this issue.
Please ask away and I will try to answer them the best that I can.

C.Perkins