Disproportionately High Value # 3: JIS Screw Drivers  

When I wrote for Motorcycle Consumer News magazine, I watched for products to enhance a rider’s ability to enjoy, maintain or repair their motorcycles.  When I found, bought and wrote about JIS screwdrivers, it generated a great deal of reader mail.

As regular subscribers to my newsletter know, this series is about items or experiences which turn out, in hindsight, to be far more valuable than when first encountered or purchased.  It’s been fun to write and a blast to hear stories from many of you about your favorite stuff.  When I bought my set of JIS screwdrivers, I only thought they were neat screwdrivers.  After many years, I now find them an absolute joy to use and I’m jazzed they’re in my toolbox.  Let me tell you why.

If you’ve ever run across a rusted or corroded Phillips screw nearly impossible to remove and you fear you’re about to strip off the top, it turns out there is a reason why this is happening.  Philips screws were actually made to resist high amounts of twisting effort.  A JIS screwdriver will help.  They look like standard Phillips head screwdrivers, but they’re not. They’ll work on Philips head screws, but where they really shine is on any bike made in Japan.

Nearly every product from cameras to carburetors made in Japan conforms to Japanese Industrial Standard (JIS) 4633B-3/1991.  Although using a Phillips screwdriver on JIS screws will work, using a JIS screwdriver is mind-blowingly different. JIS screws are far less susceptible to stripping and a JIS screwdriver provides a satisfyingly, snug feel you only get when you’re using the right tool for the task. This is the rare treat you get when something just fits together perfectly.  But it’s not by accident.

Henry F. Phillips invented Phillips screws/drivers in the 1930s. He created them for automobile assembly lines. In addition to self-centering, his Phillips screwdrivers were built with an angle on the flanks and had rounded corners. This taper on the driving faces was created to cause the screwdriver bit to “cam out” of the slot before twisting a screw head off, which was a requirement for automated assembly lines. But what fills the requirements in an automated environment is prone to stripping when used by hand.  Unlike a machine, people are unable to deliver an exact and specific downward force to an appropriate screw and, as a result, the chances of stripping the head go way up.  JIS screwdrivers, on the other hand, have parallel faces on the driving flanges and will not cam out. They are likely to break whatever was keeping the screw from giving way (good), or strip the thread with excessive force (bad).  They were designed for humans to use, with appropriate human judgement, and not on an automated assembly line.

Identifying JIS screws is simple; they often have a small dot to one side of the cross slot.  Using a JIS screwdriver in the right situation on the appropriate screw head feels really good.  Every time I reach into my toolbox and come out with one of my JIS screwdrivers to use on a Japanese made product, I can’t help but smile. Not a giddy smile, but a smile, okay?  It is a genuine pleasure to have something work so well.  And it explains why so many Phillips head screws seem to get so bungled up and why it feels like they push back when pressure is applied.  And if you’re a tad pedantic, you now have something new to lecture your fellow weekend mechanics about the next time they visit your workshop.

Using a JIS screwdriver on regular Phillips head screws has some benefits, but you won’t get all the advantages. However, don’t apply a Phillips screwdriver to JIS screws, as it really won’t work well.

At one time, JIS screwdrivers were expensive and hard to find.  A few years back, none of the common tool places (ACE Hardware, Lowe’s, Harbor Freight) carried them.  But Amazon.com does and you can now buy them for  $20 for the most common sizes.

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