Then I went to the 1-1/2" spade bit that I hardened. Snapped that puppy like a twig.
The one on the right is a new one, fresh out of the package. The one on the left was heat treated, but not tempered, and was thus brittle. You can see where it snapped off not only the center point, but the barbs on the ends as well.
Same with the 1-1/4" that I was using to do the corners. Trip to 'Nards to get more bits and some other needed items (also picked up a titanium Forstner bit for doing the upper joists)
Forstner bits are cool. They make really nice holes, and they last a good long time. I've been using the spade bits because I don't need the holes to be pretty, but the cheap-ass made-in-China bits piss me off.
Still had a problem with the corner posts, in that I still needed to pass the ENT conduit through it and have it make the corner; it's a kind of a sharp curve, and they don't make drill bits that cut curved holes.
On the way home I had a thought.
I dug out a handy tool that I call Frost's Nemesis: it's a 5HP angle grinder with an unguarded circular saw blade attached.
Highly dangerous. Don't try this at home. This thing will cut through wood, steel, brick... and flesh if you're not careful, and it's really easy to kick back into stuff, so I only use it for special occasions like a zombie attack or chewing a channel in a corner post for running conduit. Since there were no obvious zombies, I used it to cut channels in the corner posts for the conduit.
Just for fun, here's a picture of the drill I'm using.
The coke can is in there for a sense of scale. I think it's about 3-1/2 HP, which is why it's able to snap off drill bits without twisting my wrists off.
And here's a pic that's just cool: