jump to example.com

post-loxheader.jpg

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.

The Test

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.

post-lox4.jpg

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.

 

post-lox1.jpg

 

After ten cycles, it’s really starting to look bad.

post-lox2.jpg

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.

 

post-lox3.jpg

Read on to page 2 where we try the same thing with LOX fasteners.

pages: 1 2

 

20 Responses to Hands-On: LOX Screws

  1. Quentin Liedtke says:

    It still surprises me that the Robertson screw is not popular in any other country than Canada. For those of you that do not know about the Robertson screw, see this wikipedia article: http://en.wikipedia.org/wiki/Robertson_screw

    The advantages of the Robertson Screw are:

    1. Its driver bit sizes are standardized so you know that the bit that you have will fit the screw you have without having to “lean into it”

    2. A Robertson screw will stay on the end of the driver bit, enabling you to drive a screw without having to hold the driver with one hand and the screw with the other.

    3. The design resists “cam-out” like the LOX screw. I have not done any formal tests but I would suggest that it’s probably 5X’s better than a Philips’ screw (but not as good as a LOX screw).

    4. It’s Cheaper than a LOX screw and bits are more readily available (in Canada at least)

    Quentin.

    • Matt says:

      You guys ever heard of timberloK fasteners? Basically a cross between a bolt and a screw: long shank of relatively small minor diameter – when compared to major diameter of external thread, low thread count [per unit length] w/t large [coarse] thread pitch, fluted, capped (washer-like) to male hex head driver. Really, really great for self-driving through softwood. Not so great for self-driving through hard woods! The problem? Nope. Not cam out. Nor even stripping [cutting of] wood fibres – or external thread – this rarely happens as flutes to large. Nope you get to the point where you can apply so much torque that you begin to twist up the shaft of the wood screw to the point of failure. Always at the screw head. Yep. That’s right. It just snaps [shears] clean off. Major bummer. Unsecured load. Large sharp, sticky out piece of metal entirely resistant to extraction. Just waiting to appear through the other side of someones hand. Probably yours. Whoops.

      Mental note.

      1. Stuff always fails. At its weakest point [usually].
      2. Therefore a rational person would always design upto the weakest point. Not beyond. B/c what is the point?

      Screws are a case in point. Camming out was seen as a major flaw. To some extent that is true.

      Solution: Design a new screw drive that resists ‘Camming Out’.

      Job done? Er. Not quite.
      The new screw drive system often surpasses either the strength of:
      1) the material it purports to join. E.g. You can screw the head straight through piece of timber and the next or.
      2) the material it is made from. E.g. too much torque at the driver not being able to be transmitted to the thread itself. Result failure at the head.

      Of course we can get round this. Better screw materials – but see 1. Or, just use a clutch on your driver. But then the clutch usually slips before driving home in hardwoods – even on its strongest setting. Or, pilot drill: thus defeating object of a self driving/tapping screw. And of cause, repeated use [of the clutch] causes this to wear out. But not before the battery decides to self terminate and depart forever. We can’t buy a new battery cos it works out to be more expensive than the latest ‘brand new’ machine so we buy it with exactly the same flaw as before: a bloody rubbish battery! Pah! But thats another story entitled ‘Designed to Fail’. Pah. Cordless. Pah. Use corded. Use air tools. Use your teeth.

      Anyhoo. The point of this overlong rambling diatribe is to ask whether the same happens to the lox screw??? Does it fail at the screw head when driven in?

  2. Rob says:

    Do we really need a new screwhead? Torx, square drive, hex drive. Where does it end?

    It’s true that Phillips screws don’t take to multiple uses but for for wood screws, the wood doesn’t really take it that well either. For the most part, I consider woodscrews mostly permanent, driven once maybe twice. Things that need to be repeatedly disassembled I would use an insert and a machine screw.

    I’m still waiting for the “Arthur head” screw to take hold.

  3. james b says:

    I know torx get used quite a bit in automated assembly machinery because they can be vacuum sucked into a driver then have a rotating bit pressed into the fastener without it tearing up the bit or fastener. Phillips do the same thing in reverse when you use one of those drywall depth setter attachements. I wonder how these do when you put a moving bit onto a halfway sunk screw, or if they can be used with a drywall screw depth setter.

  4. Toolaremia says:

    This really does appear to be nothing more than another attempt to use a patented “improvement” to try and increase revenue in a commodity market.

    And as the first comment suggests, this is probably not much better than the Robertson (which rocks), the patent on which has already expired.

    Philips was /designed/ to cam-out. It serves a purpose, of which woodworking should not be one, IMHO.

  5. Nick Carter says:

    Just my favorite screw tip: If you have a screw that is camming out/stripped, grab some loose grit from under your bench grinder, mix with oil or spit and apply to the screw head and driver. The grit bites into the recess and driver and allows you to get it out (or in)…

    They sell bottles of silicon carbide grit and oil for this purpose but spit/grinder grit is free and available.

  6. Jason says:

    Reasons why the Robertson screw remain unpopular outside of Canada are suggested in the Wikipedia article. It basically distills to issues of licensing proprietary technologies. Luckily, ninety years later, patents and licensing are no longer issues.

  7. Jake Strait says:

    I’ve seen the square (Robertson) screws with more regularity in the last few years. If the LOX is to be successful they’re going to need to get the price down and get those screws in every store. I would think the manufacturing cost of the square drive would always be less, so this might only be a flash in the pan.

  8. Trey says:

    Actually, the camming out of the Philips head makes it perfect for woodworking and hanging sheetrock. The head cams out before you use so much torque that you strip the threads in the wood. Once I used square drive screws to fasten two sheets of plywood together. Every other screw stripped out due to too much torque from the drill. Yes,
    you could change the torque setting on your drill but why bother. You don’t need to do that with Philips screws in my experience.

  9. Rob says:

    Trey makes a good point. There is a drywall screw tool called a “Dimpler” that uses the camming action of the Phillips head screw to set it at a certain distance just below the surface of the drywall without overdriving it.

  10. Toolaremia says:

    Trey, the problem with using the cam-out “feature” of the Philips is that it destroys the driver bit. That’s why they sell “chaw-cups” with 100 bits in it at the hardware store; you go through several a day if you install drywall for a living. With the Robertson and a clutch, your bit lasts years. And you never slip out of the screw and clobber the drywall.

  11. DeadlyDad says:

    Philips screws were specifically designed for use with power tools, so that, instead of accidentally driving right into whatever you were screwing, they would ‘cam out’ when the head came in contact with the material. Robertsons, on the other hand, were designed to /never/ ‘cam out’ or slip. Except for drywall, I can’t think of any contractors I know who use Philips screws when Robertsons are available. It is simply better technology.

  12. Michael says:

    I use both Phillips and Robertsons daily. Both work, but the Robertson’s is superior. The Square drive does cam out during hard use (esp. with harder woods). As someone who is often paid to fix other people’s mistakes, I always cringes when I find an old Phillips to remove. Old sqaure drives can be sticky too. I’d welcome an industry wide switch to LOX simply because you never know when you need to remove a screw, and anything that makes that easier is something to consider.
    Building decks with hard woods like Ipe and Teak would also be an ideal situation for the LOX. Both of those woods can casue cam out quite easily, even with a square drive screw. You could pre-drill, but with 1000 screws that could get tiresome.
    Some of the same “cons” against the LOX are the same I heard about the Robertson drive (and probanly the same things some said about the Phillips when it was developed to supplant the straight slot).
    The market will determine acceptance. I expect to see the LOX around for awhile.

  13. [...] Hands-On: LOX Screws Professional fence and deck builders know that there are some better alternatives to the Phillips head for heavy-duty driving.  LOX is one of the newest, and we tested it by repeatedly driving and removing a single screw — something any experienced carpenter would studiously avoid.  The LOX screws fared exceedingly well compared to Phillips-head, but many readers questioned its high cost — and whether it’s really a necessary improvement over the Robertson type. [...]

  14. Jay says:

    I wonder if the Phillips and Lox screws in the demo were verified to be identical in all respects other than the shape of the driving recess. Granted that there are advantages to the geometry of the Lox, but the screws photographed seem to be of different alloys and thread patterns. A made-in-China mild steel zinc-plated Phillips against a grade-8 Lox is hardly a fair test.

    What about the clutch-head? That seems to have merit as well.

  15. [...] LOX screws — the ones with the funky drive recess — really do work, as we proved last year.  We drove and pulled one of these literally ’till we got tired of doing it — we had to wear welding gloves to hold the screw — with almost no visible cam-out. [...]

  16. [...] LOX screws are so strip-proof, you’d practically have to take a drill bit to ‘em to ruin ‘em.  The same goes for spline bolts — good luck stripping them — plus many spline wrenches are “backwards compatible” with hex, twelve-point, female Torx, and square-heads, and they’re more effective at turning 50% rounded fasteners.  Now the Wright Spline takes another step. [...]

  17. _Jon says:

    I’ve used a combo-phillips / square head from Home Depot on some decks and tables recently. The box came with a blue bit. Very nice. In a pinch, I used a phillips bit to remove some screws to get a panel open.

  18. Rich says:

    Lox is by far a superior screw head to anything on the market today. Square drive or Robertson head is a great drive, but noting compares to the torque of a lox recess.

Leave a Reply

Your email address will not be published. Required fields are marked *

*

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>