Over the years there have been surprisingly few changes in basic fastener head design. In fact, the last widely accepted design change was pretty much the Phillips-head design — in 1936!
In 2001, LOX decided to try and take on the industry standard, offering a new design of “fastener recess” — the part of the fastener’s head that your driver’s bit grabs to drive it. Their “offset-square” design offers 12 points of contact. which they say lessens your need to “bear down” on the driver to keep the fastener engaged — and reduces stripping.
Of course, never being one to believe what we hear, we put some LOX screws to the test.
As you may have noticed in our tests of Bosch’s I-Driver and Litheon Pocket Driver, we’ve driven our share of Phillips-head wood screws. After driving 185 of them in relatively short succession, we learned a thing or two about the driving process.
One thing we discovered very quickly was that you can only drive a standard screw a couple of times before it starts to strip out; One of the hardest things we’ve done to screws is to repeatedly drive and remove them.
So that’s exactly what we did with some of the screws LOX sent us to check out. We drove them, removed them, and drove them again over and over again to see how long they lasted.
Our test rig was simple. We grabbed a a 2×4 from the bin, clamped it in our (well worn) Black & Decker Workmate and started driving screws. We began with a standard Phillips-head screw of similar size to the LOX test screws.
One note: Screws get H-O-T when you drive them and remove them quickly. Even one cycle is enough to heat the screw enough to burn you. You’ll notice in the pictures that we’re using a welding glove to hold the screw. It’s not just for show.
We started with the Phillips head screw. After just five cycles (drive then remove) the bit started to slip. You can see in the photo below how the edges of the recess are beginning to angle-off.
After ten cycles, it’s really starting to look bad.
After fifteen cycles the screw was essentially useless. You can see (below) how the sides of the recess are becoming rounded. If we applied more than minor torque to the screw in this condition it’d round completely.
Read on to page 2 where we try the same thing with LOX fasteners.
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