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Why torx?

Last night I aligned some headlights. The job required a torx screwdriver, no problem. But it occurred to me – why?? Why should these screws have torx heads? In fact, why is there torx hardware at all? Aren’t Phillips and hex heads good enough?

I guess they may be easier to use with automated/robotic assembly. Used to be they also might have been used to keep folks out (old Mac), but that’s gone now.

Perhaps it is to make it harder for someone to tamper with your headlights.

I asked my brother-in-law (retired Chryco plant manager) years ago.

Says that when factories started to get automated…it was a lot easier for the machines to use a torx instead of a phillips or flat. Lot less chance of slippage.

It’s the robotics.

Yeah I’m sure its the automation aspect but ever try and get a rusted phillips headlight screw out? Torx has a far better grip to eliminate slippage.

I’m a robot! I’ve found that the hardest tool to use is a flat blade screw driver. The second hardest is a Phillips head screw driver. The easiest by far is the torx. You put it into the slot, turn it, and the bolt loosens. You hardly need to lean on it at all - a can of corn.

The correct term is “Cam Out”. Flat bladed or Phillips screwdrivers will cam out of engagement with the head of the screw if enough torque is applied. Torx, as was said, won’t do that.

Torx also allows more toque to be used than either a phillips or a hex head. This is sometimes advantageous for ceratin tight areas where a notmal bolt won’t fit well.

Torx has 6 faces, 2 more than Phillips head. More area lowers pressure, lessens the chances of stripping. Hex is good, but it requires a deep recess for the head and sometimes there’s no room for it. Notice how much more room a bolt and socket takes compared to a screwdriver.

Beyond just more apexes, torx heads have far more surface area for the driving tool to mate with than other types of heads, and that area is distributed evenly in six directions. Torx is much less prone to tool engagement problems in automated installations.

JT, your post made me chuckle. What you say is so true.

Thanks, SMB. I try to have a good time and It’s good to know that someone else has a little fun with me.

Anyone who has ever worked on Japanese motorcycles will curse anything to do with a Phillips screw.

"Anyone who has ever worked on Japanese motorcycles will curse anything to do with a Phillips screw. "

Phillips screws can be bad enough in that they cam out easily, but it’s especially bad on Japanese motorcycles and equipment because the Japanese Industrial Standard Phillips screw is not the same as the ones we use in the USA, and our screwdrivers don’t fit them very well. Most people aren’t even aware that there is a difference in the screws. A JIS screwdriver will fit a JIS screw very well, much better than the US standard screwdriver fits a US standard screw.

Using air tools to assemble things with Phillips screws is a pain and a half, especially when you get those tiny, tiny screws, like the ones used for the dryer door hinges. They constantly slip out of place and you can wind up scratching the paint with the air tool. For most things we use hex heads, but those needing to be more flush(door hinges) use the Phillips head.

Thanks JayWB, now you tell me! Only 40 years late. I became much too used to an impact driver when working on my '67 Suzuki X6. Of course, that was when a 250cc was ‘mid-sized’…

Like I said, texases, most people aren’t even aware that there’s a difference.

Get yourself a set of JIS Phillips screwdrivers and I think you’ll be astonished at the improvement.

I have a JIS crosshead screwdriver in the tool kit of my motorcycle and I get it out whenever I work on something with metric crosshead screws. It’s amazing how much torque you can apply without the screwdriver camming out when you use the right screwdriver.

It doesn’t take a Japanese motorcycle to get me cursing about Phillips heads.

In addition to torx, there is torx plus. Apparently it is more friendly to robots than torx standard.