[Halfnutz]

I do it all the time with a simple F20 at the beginning of the problem and a F40 at the end of the block.

Just run the program, and wherever you hit a problem stop the program, open it in the editor, back up a line (or two) add a feed change to the first line of the block and one to the end of the block, and resume cutting at where you stopped. Once you run through the program once you have the problem fixed for good. If its a program you use more than a little, its not a big deal.

I use diferent feed rates throughout most of my programs. If Im at the beginning and doing the roughing with little or no Z movement and a simple raster scan I will crank the feed up to 70 or 80 IPM and then slow down to 30-40 for areas with lots of contouring and multi axis movements.

I geusse its a pain, but I only have to optimize the program once, and I can take a two hour program down to an hour sometimes. If its a design I like and plan on using over and over its well worth it.

I dont know exactly what your doing of course, maybe your talking about a six hour program with a tab every fifty lines, who knows, but its a something to consider.