I tested a 16 gauge Powernail cleat nailer today for an upcoming installation of 3/4 X 3 1/4 Brazilian Cherry.

I nailed a bunch of sample pieces with it, and it seemed to work fine. There was no apparent splitting when viewed from the top, and the installation seemed very solid. Every nail appeared to be set correctly, with no cracks in the wood around it.

However, upon removal of the wood from the sub-floor, just about every board had cracks on the underside around the nail penetration area. A couple of boards split the tongues completely off when I removed the boards.

Of course, the damage could have been caused by the removal process, even though I tried to be as gentle as possible prying them off.

I guess my question to those with experience out there would be, is this underside splitting normal, acceptable (to a degree), or likely caused when I removed the boards?

I'm a complete newbie, but I've done my testing by putting an extra length of hardwood on a scrap sheet of plywood. I would think trying to pry it up again could cause damage, but really don't know.

Braz. cherry is harder than most woods. You can expect some splitting tongues. I prefer staples, they just hold better. They will also split the tongues or underside of boards, but still hold better. As long as you don't split or break off too many tongues, and your moisture conditions are good you'll be ok. You'll find boards so hard a nail won't go thru. We usually plan for a little more waste with Braz. cherry, so we can throw out the boards if tongues get badly damaged or we can't nail thru them.

Some installers are now using thinner 18 gauge flooring cleat/nails for harder exotic nail down installations. Back in the day...even as recent as ten years ago they didn't exist...or I never recalled them. It was either staples or nails and that's it. Reasons for their use is to cut down on tongue splitting which can lead to squeaky floors.

Something to consider.