Kreg XL Heavy Duty 2X pocket hole screws

[Michael Kellough]

Also for 3X stock. (To skip the setup scroll to the last sentence.)

These #14 X 2-1/2 inch screws have incredible holding power!

I’m building a temporary shed (long story omitted) 8 feet by 20 feet. I hope to replace it with a bigger structure in the near future so I’m using screws instead of nails as much as practical. The “floor” is existing decrepit concrete (every couple of feet pitched a different way) so I can’t assemble a wall and then erect it.

Each post is bespoke so I braced the first 10 foot 2x6 wall plate in the air and added the custom posts for each end to make it level. To butt join the second 10 foot 2x6 I used the Kreg XL jig and drilled 3 pockets, braced the board and tightened the screws.

So now I have a heavy 10 foot 2x6 (I always select the heavier timber from the stack) screwed to another 2x6 at one end and temporarily braced. I stumbled on the uneven concrete and knocked the brace out and instinctively crossed my arms over my head to ward off the falling timber. Nothing happened.

3 XL screws secured a heavy 10 foot 2x6 by the end, totally cantilevered, completely unsupported! Heavy duty indeed.

 

[Packard]

I googled: Kreg XL Heavy Duty 2x hole screws, performance data and specifications.

The closest to an answer that I found was this:

XL Pocket-Hole Screws are optimized for use with the Kreg Pocket-Hole Jig® XL, the Kreg Jig HD and 1 1/2" and larger stock. These large 2 1/2"-long #14 hardened-steel screws provide incredible shear-resistance, and have a Protec-Kote™ finish with three anti-corrosion layers for long-term moisture resistance. #3 square driver.

I would be reluctant to assign these screws structural duties with only that as a performance spec.  Perhaps your google search will come up with something more than “incredible shear-resistance”, which does not sound like a test result to me. 

It may be everything you hope it to be, but before construction I would take care. I am reminded of Ronald Reagan’s quote:  Trust, but verify.

 

[Michael Kellough]

I know toe nailing from both sides would not hold. If the joint was sandwiched with plates and screws on both sides it would have held but probably opened a little. The result from using just three screws was extremely impressive, the joint did not open even a smidge.

 

[smorgasbord]

...I always select the heavier timber from the stack...

Just wanted to note that in a stack of construction grade 2-By lumber, the heaviest ones are probably simply the least dry. For Doug Fir that may be what you want, as the wood dries it'll grab the fasteners tightly, but I wouldn't assume the heaviest timbers are the strongest. They'll probably just warp the most as they dry. A portable moisture meter might be worth carrying to the yard to verify.

That said, I too have used the Kreg XL with the #14 2 1/2"-long screws and been happy, but my application was repairing a wood fence where the 2x8 cross beams had simply been toe-nailed into the 4x6 uprights and the top ones were pulling out.

 

[Hipplewm]

Kreg also makes a 4" long hardened steel coated screw.  We built a chicken coop and I used 4x6 for the corners and 4x4 for the base (We have to harden against predators) and used those to connect - I know a chicken coop isn't real structural, but it has survived 2 hurricanes so far....

 

[Michael Kellough]

The screws are also well made. The recess in the head holds snugly to the #3 square driver and the screw doesn’t wobble when driving into wood without a pilot hole (or pocket hole). And it starts to enter the wood quickly, especially for a #14 screw.

The best price I’ve seen is from ToolNut. $16 for a box of 125 screws (2-1/2”).

 

[Michael Kellough]

...I always select the heavier timber from the stack...

Just wanted to note that in a stack of construction grade 2-By lumber, the heaviest ones are probably simply the least dry. For Doug Fir that may be what you want, as the wood dries it'll grab the fasteners tightly, but I wouldn't assume the heaviest timbers are the strongest. They'll probably just warp the most as they dry. A portable moisture meter might be worth carrying to the yard to verify.

That said, I too have used the Kreg XL with the #14 2 1/2"-long screws and been happy, but my application was repairing a wood fence where the 2x8 cross beams had simply been toe-nailed into the 4x6 uprights and the top ones were pulling out.

When selecting boards from the same bunk (it’s Douglas fir for construction around here) the boards all have about the same moisture content so the heavier boards are usually those with a higher proportion of latewood and are indeed stronger. You can confirm by looking at the end grain.

 

[Packard]

The building code for where I live calls for 2” x 8” for floor joists.  My home was originally the builder’s home and it has 3” x 8” for most of the floors.

It is almost impossible to drive a nail into these joists, and I routinely pop the heads off of screws trying to do the same.  Oversized pilot holes are required. 

I believe that these are Douglas Fir. So, would that make these the heavy ones or is it just the age of the wood that does this?

 

[smorgasbord]

So, would that make these the heavy ones or is it just the age of the wood that does this?

Almost certainly the age of the wood. Douglas Fir, like Southern Yellow Pine, does get harder with age. It's one of the things make it such a good material for building framing - you can nail it up and within a few years it's gripping those nails really tightly. A few years back I helped a friend install a convertible roof hoist into his at least 50 year old garage, and we ended up using my large impact driver to set the screws, whereas for a cross beam we installed was much easier to screw into.