I'm going to be installing 3 1/4 x3/4" Cumaru diagonally thoughout the house, but I'm trying to avoid having to go diagonally down the hallway. The hallway is L shaped with a 13' section with the joists running down the hallway. As far as I can remember they are 16"oc 2x10 with 5/8" TG subfloor. Would it be safe to run parallel the joists for that section of the hallway?

*Also rather than start a new thread, I picked up a used Bostich 18g brad nailer, will it work on Cumaru given the hardness and would the 18g nails be OK for face/bling nailing if I were to shot a few more in each plank?

IMO it's no problem running parallel to the joists down that section.

The Bostitch 18ga. brad nailer is a great gun, I use one, it will definetely work fine on Cumaru. Normally I use the 16ga. for nailing 3/4". But the 18ga. will work. Like you mentioned, a few more fasteners. I would use PL adhesive under the areas that you blind nail & face nail.

Oh, You'll have to go a little higher psi on the Bostitch 18ga into Cumaru ( probably 80-85psi ). But if you go too high that gun will misfire. So make sure the brad is in the wood !

Thanks Howard