I'm pretty fussy about how I mount drivers, (some would say anal). I've tried t-nuts, wood screws into MDF, nut and bolt and I'm sure some others. Like the look of button head machine screws, but really don't like t-nuts so I've used this several times now with success.
Centering bit for hole location

Gettin' holes perpendicular

Here comes the crazy part. Who knew you could tap MDF? ( also part of the reason for layer cake)


Drip in some Cyanoacrylate (how's that for ostentation?). It's super glue

Let it dry overnight, run tap again to clean up. Slow and gentle.


Baffles were cut oversize so they were easier to work, but didn't want the BB core on the edge so I trimmed and banded perimeter

Round over on the backs using my "mega base" and the vacuum setup from earlier

Here's where we stand now

Next puzzle will be grill frames, stay tuned!