Thank you OP & thank you whoever bumped this up. I have a standard office desk that I sew on. Since I'm 6'1" with a 36" inseam, my knees are quite close to the underside of the desk. (at work, I had to take out the center drawer) If I did a cut in & dropped the machine (not a cabinet machine), I'd bump my knees on the dropped wood. Owie. (Knowing it is there & staying away from it does not work for me.)
I have an old (something or other) machine with a vertical bobbin. I've been thinking of setting it up as my FMQ machine (the bobbin thread doesn't have to make that 90* angle like a drop in bobbin.
This table idea will work for setting up that machine for FMQ!