I am planning on nailing down some 9/16" x 4" x 72" strand woven bamboo. This stuff is very hard (twice as hard as traditional bamboo) and I am having trouble with my cleats:

- splitting the tongue, and
- not sinking deep enough

I am using 2" Bostitch L-cleats (16 guage I think). I am using a Ramsond nailer, but have had similar results with a Bostitch. I shimmed the baseplate and think the cleats are going in at about the right place. I pushed the air pressure up to 100 psi, but the cleat heads are not set deep enough to allow the next board to set properly.

My tests have been done on 10-1/2" long sample pieces, nailed to a 2x6. For real, I will be nailing to 1-1/8" of plywood.

My questions are:

1. Does my cleat look like it is going in at the right place?
2. Is there anything I can do to get the cleat to set properly?
3. Is this amount of cracking OK? The crack right of the cleat is the longest and is about 3/4"-7/8" long, tapering down from the width of the cleat.
4. Is there anything else I can do to reduce the cracking? I have read about putting some lubricant on the tips of the nails, but haven't tried that yet, although I'm not too optimistic.
5. The cleat in the picture below is in the middle of a 10-1/2" x 4" sample of bamboo. Will I possibly get less cracking on a longer board?

TIA.

I personally think you are using too much ammo. You don't want any splitting at all if you can help it.

What type and gauge fastener does the manufacturer recommend? I'm thinking an 18 ga. narrow crown staple would work better with a 9/16" product.

From what I have been lead to believe, the strand woven is really hard, and drilling and hand nailing is the way, if you want it fastened down, instead of glued.

I have never tried my HighPro AS4090 on stand woven, to see if it will take the thin gauge, 1¾ staple.

The manufacturer recommends 15 gauge nails or staples. I contacted them with my troubles and they said I might need to play with the air pressure, but I should be able to get it to work.

Jerry, everything I've read on this site suggested that staples would be more likely to split the tongue than cleats. Do you disagree?

I have read a couple posts on this site that recommended lubricating the cleats with 3-in-1 oil or wax. I am afraid that if I lube, they'll go in better, but also come out easier. Thoughts?

I tried a test where I pre-drilled a hole and pounded in a cleat with the pneumatic nailer (90 psi, I think). The tongue did not crack, but still the cleat head was not sunk enough to allow a proper alignment of the next row.

I having a sinking feeling that Jerry is right - this stuff is just too dense/hard for that 16 gauge cleat head to get buried deep enough. I am really not interested in drilling and hand-nailing my whole project.

I need to state right now that I have zero experience with the floor you are installing. If the manufacturer recommends a 15 ga. then they should know what they are talking about.

Question... do you have a 9/16 boot attachment on your gun? From your photo it looks like the cleat is at too shallow of an angle.... not quite steep enough.

As a generic or general statement I do not agree with that.

Thanks for the comments Jerry. You asked

I have a base plate that is for 1/2" - 5/8", so with my 9/16" wood right in the middle of that range, I thought I would be OK, but it was going in too low, so I shimmed it up - quite a bit, maybe 1/16". I was going to try raising it a tad more thinking that I wanted to keep the head away from that tongue that wants to crack.

If my angle is too shallow, then I could shim up the front of the nailer base plate and see if that helps. I was actually thinking of trying the opposite as I figured a more vertical cleat would tend to put more force on the tongue.

I am concerned, however, that even when I pre-dilled, the cleat head would still not sink enough, so even if I solve my cracking tongue problem, I still will have cleats not sunk (I think that is the technical term ) properly ...

What material is that 2x6 test board? It may be a harder material than the plywood subfloor. That could be one possibility the cleat won't seat flush.

It is Canadian softwood of unknown species, but would be spruce, pine, or fir. Not hard stuff.

In some more experimentation this afternoon, I've noticed that even if I get a cleat in with a small amount of cracking, the tongue is still displaced outward.

I spent the afternoon trying all manner of permutations. Shim a little bit up, shim a little bit down. Psi down to 70, psi up to 115. Shim to tilt the nailer forward, shim to tilt the nailer backward. Cleats dry, cleats oiled. Not great results, overall.

My best result was 115 psi, nailer tilted back a bit, and some air tool oil on the nail. But could have been chance, as I only did one test with those parameters. Here is a pic:
I didn't adjust the height after tilting it back, so the cleat went it a bit high. There is obviously still a splinter/crack, but it is relatively small and above the tongue, which I assume is preferable.

Still problems though, as even though I think the nail is in far enough, the tongue is displaced horizontally outward, so the next board can not be snugged right up.

I took a bit screwdriver and tried to pry up on the tongue at couple areas that had been cracked by my tests. I couldn't budge it and no cracking noises. Is it possible that the strength is mostly unaffected by these small cracks? Or would something show up over time?

My nailer is rated for max pressure of 100 psi, but I am assuming there is some safety margin built in, and I would think there could easily be 10% error in my pressure gauges. How crazy do you think I am to go above that?

My projects always seem to be ordeals, but I really don't know what to do with this one. I might try to get some staples to try tomorrow.

most bamboo is 5/8" thick,, not 3/4".
Maybe this will help?

My bamboo is 9/16".

I spoke to my distributor/manufacturer and was told to try 1.5" 15 gauge staples (I have been using 2" 16 gauge L-nails). My nailer only supports 15.5 and 16 gauge staples, and I can buy 15 gauge staples locally. In fact, I can't locally buy 1.5" flooring staples in quantities less than 7,800, which I am hesitant to do until I know they'll work. I did manage to beg a few samples of 1.5" 16 gauge and 2" 15.5 gauge staples, so will give them a go and see what success I have.

20 bucks says the staples will work better. If I'm wrong I will need to borrow that 20 bucks from Ray .

I'm telling you, the HighPro As4090 was made just for this flooring. Well, maybe not. But it will be way better then what your using now.

Floorguy said:

That looks like an interesting nailer, but why is it better than a traditionally designed flooring nailer? I thought the whack to squeeze the boards together just before the staple goes in was a universal design of flooring nailers.

Jerry said:
Looks like Ray owes you 20 big ones. I went into town to get some staples yesterday, but the smallest quantity of 1.5" flooring staples I could find was 7,800 - reduced choice is one of the hazards of living in a small town. I was, however able to beg some samples of 1.5" 16 gauge and 2" 15.5 gauge floor staples (.5" crown).

At 100 psi, the 16 gauge staples went in well with a minimum of cracking, but the crown wasn't sunk enough for the next board to fit in correctly. Above 100 psi, the crown was deformed, and still not sunk deep enough, so the 16 gauge just didn't work - the stuff is just too hard for a staple that thin.

The 15.5 gauge staples worked better, but I needed 120 psi to get them hammered home correctly, which is really pushing my nailer and my compressor. And there is still some minor cracking, and the tongue bulges out a bit. But it is the best I can do, so I bought 7,800 1.5" 15.5 gauge staples. With these shorter ones, I can bang them home with more like 100 psi - that is if I find the sweet spot. The optimal range to align the nailer is extremely small - the thickness of one layer of duct tape can make a big difference. There is a small amount of cracking around the staple, and a wee bulge in the tongue, but the next board seems to fit in OK.

I spoke to my distributor again today and was told that a small amount of cracking was fine so long as the tongue/board is not materially weakened. I stuck a big screwdriver under some of my cracked tongues, and I couldn't budge them without some serious force - couldn't really tell the difference from virgin tongues.

Tomorrow the flooring starts going down. Thanks to all who offered suggestions.