Why such a huge gap between rough and finish?

[sourceminer]

Im trying to figure out why so much wood is having to be cut out when doing the finishing pass. Or what am I doing wrong?

[Xxray]

Purpose of a roughing pass is to hog out a majority of material to save wear & tear on finish bits, right ?
Why would you want less of a gap, to save time ?
Maybe I'm not understanding your question correctly.

[sourceminer]

If the purpose of the roughing pass is to hog out a majority of material, then Yes why is there so much of a gap here as pictured?

[Xxray]

Tough to tell any dimensions with a flat cut like that, looks about right to me. One thing that will throw off proper depths one way or the other is incorrect Z input.

[Adrian]

What's your machining allowance in step 3? Where the transition from the deep cut to the shallower cut is is there a curve there in the final piece? What's the difference in size between your roughing and finishing toolpath?

If you could attach the Cut3D file it would make it a lot easier to work out what is going on as there is so much that can't be seen in a picture.

[adze_cnc]

The roughing pass appears to be using the z-level roughing strategy. Here the pass depth comes into play. There could be as much material left as the pass depth less the machining allowance.

It looks as though a really big ball-end bit was used for roughing. So if the pass depth is 9mm and the machining allowance is 1mm there could be 8mm of stuff left behind for the finish path to clean up.

[sourceminer]

Thanks for your help. I will keep an eye on that in the future.