You may have seen a follow up comment I made about thinking of using a different router bit to do the profiling.
Well I got a scrap of wood and did some test cuts just to satisfy my curiosity.
History: The NGR boxes were profiled with a 90Deg Grooving bit.
So I set that up first and cut the profile, I then used the Combination bit and repeated the process.
These are the results I obtained:
This is both the profiles and the respective bits together
The 90 deg grooving bit close up, and its respective profile result.
The image of the bit close up is blurred however you can make out the chisel point similar to a twist drill.
What is very obvious is after the fact there is a flat on the 90 deg vee cut in the timber, and its the chisel point producing this effect.
Now the combination bit close up, and its respective profile result.
The flat edge on the combination bit is more obvious and readly recognisable even when examining the bit
You could if you wanted use the 90 deg Grooving bit and reproduce the same result as the combination bit simply by changing the router bush size and re routing the profile again.
Dependent on just how much flat was acceptable on the profile would determine your choice of bits.
If it was zero or thereabouts neither of these bits would do the job and you would be looking at a laser point bit or similar, of which is not something you would be likely to find in the common garden variety router bit sets.
After seeing the results I am happy with the choice I made for the NGR Box work.
-- Regards Robert