Confusing carve times for a simple design

I have a couple of questions about carve times and bit usage if you wouldn’t mind indulging me.
I have a fairly simple design that requires carving out shapes and clearing out pockets.
Like this (though there is more to the design, this gives the overall example):

The sizes are big enough for a 1/2" bit to clear the pockets and then an 1/8" bit to finish cleaning it up.

When I just use an 1/8" bit for the whole carve, the estimated carve time is 59min. When I switch to the 1/2" and 1/8" combo, the carve time becomes 11m + 2H 20m (at the same feed rates).

Now to the questions:
What is causing such a drastic increase in time? It seems backwards to me because in the single bit scenario the bit has to carve everything (including the pockets) whereas the combo scenario it should only need to “clean up” the edges.

I’m now posed with an issue of time vs bit usage. Obviously, the 1/8th bit will get a lot less usage by using the combo method, but that also means a 250% increase in time. What would you do and why?

Thanks for your time!

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First off, I don’t really use Easel as I’ve been cncing since before Easel was developed. I would use the half inch bit and I/8 for finish, but I’d check the depth of cuts per pass and the material selection, since a greater depth would knock off some time. I’d imagine doing the whole thing with an 1/8" bit would dull it out by the end too.

When you select bits, the other tab is cut settings, and you can click on Manual, to enter numbers of your choosing.and not rely on stock values. When I’ve used Easel, mostly to learn the software, I’ve found the stock settings are pretty conservative.

Please create a project using 2 workpieces.
one for the single bit scenario
the second for the 2 bit scenario.
then share the project.& provide the share link as shown here >>

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In Edsel, when you use a two bit design the finish cut has a default step over setting just like the rough cutting does. This is how much the bit overlaps itself with each pass. I believe 40% is the default for one bit cutting as well as rough or first pass cutting. The finish cutting is normally under 20% and I believe the default may be as low as 1%. It is under the (Machine) menue then go to (General Settings). You will see the step over percentages there. I normally use about 10% to 15% but it depends on the wood and how clean you want the cut.

I’m working on a project now that uses the same bit scenario. with the two bit cut my cut time was long like yours. two things I did was, one, increase your depth of cut . where your not taking very much off just to finish the profiles, I increase my depth of cut to .100. Second, what I did was was separate the cuts. I copied my project to a second window and used just the !/8 th inch bit to do just the profiles. This reduced my cut times to half what it would have taken with 2 bits together.