CONTINUED.....
Tips:
1.) Use a small paint can or something to outline the hole on one of the 16"x19" panels. Then use a jigsaw to cut out the hole. (Drill some holes to insert the drill into)
2.) Make sure to let the glue dry before drilling
3.) If you don't overlap the panels at the corners, the panels will resonate more freely. (Forgive me. Acoustics is my day job)
4.) Use 1/4" diameter dowels as trim. It is pretty and it makes for a nice edge when you don't overlap the corners.
5.) Apply three coats of clear polyurethane to the assembled cajon. The polyurethane will make it look good, seal it, protect it, and the extra mass brings out the bass tones.
Good luck. If you need anything else, drop me a post or email.
Zach