JIS screwdrivers

[Lozza]

Never knew this until recently , that Japanese has a different standard for Phillips head screws called JIS. The JIS screw head has a very small corner radius and flat end compared to normal Phillips heads. Explains why it is so easy to munt one of the larger JIS head screws with a normal Phillips head screwdriver. Vessel and Hozan seem to be the main brands of JIS screwdrivers.

[pokey]

Your kidding me lozza? i knew that back in 74 that Suzuki used JIS . Couldnt at the time find a JIS set of screwdrivers though, tool shop just looked at me kind of like I was simple.
 A good whack with a drift( old axle) before tapping in the closest size Philips has never seen me wrong. I do have one solitary JIS driver now that only comes out for pristine jobs.

[djr]

Japanese Industrial Standard, I think that's what the JIS stands for,
 found this out a few years ago when working on Japanese Excavators.
 Had trouble with matching some Hydraulic Hose fittings that looked like European metric fittings but just slightly different, spoke to someone at the Importers who told me fittings were JIS and that  the Japanese have there own standard for all sorts of stuff {including the screwdrivers}
you would think the screwdrivers would be widely available with the amount of Japanese cars, bikes and other machinery about
but I gave up looking for the screwdrivers, good to see you found out some brands that sell them.

[TT5 Matt]

well ive learnt something new today as ive always thought phillips head was universal no matter what country. i know theres a few different star types used in the tek screw industry though which are an 4 main points with another 4 shallow points inside which make it hard to use them without the correct driver.trust the japs to be different

[rocketfrog]

I have a daggy old (Sidchrome I think) #2 Phillips I prefer to use because it fits better than most Phillips I have used for Jap hardware.

I have never given it much thought, other than that this particular driver is a better fit and does not cam out of the drive, it is probably a JIS like you say Lozza.

New lesson for me too and I have been tinkering with mechanics for 30 years.

[TT5 Matt]

yeah i brought 2 of those green handled sidchrome #2 phillips head screwdrivers when i started my trade [since worn out many years ago] and they gripped well on jap bikes

[Doc]

If it doesn't fit properly I don't use it

[skypig]

So basically, the JIS screw is designed to stop a correctly sized Phillips head driver seating properly, therefore increasing the chances of screw damage and leading to a small industry in Allen key screw sets in the '70s.

[TT5 Matt]

So basically, the JIS screw is designed to stop a correctly sized Phillips head driver seating properly, therefore increasing the chances of screw damage and leading to a small industry in Allen key screw sets in the '70s.       

yeah thats it we all did it,undo the nasty shite JIS screws with the impact driver or hammer and chisle and fitted allen head screws,thankfully yamahas had allen heads in them by 1976 and made life alot easier

[yamaico]

 A good whack with a drift( old axle) before tapping in the closest size Philips has never seen me wrong.

I've been doing this since the early seventies, but used the "T" handle of a Philips head T bar. Not only does it restore most butchered heads when you tap the screwdriver back in, it shocks the galvanic bond that forms between the zinc plated thread and the aluminium it's screwing into, which is usually the cause of the head being butchered in the first place.

[Lozza]

 A good whack with a drift( old axle) before tapping in the closest size Philips has never seen me wrong.

I've been doing this since the early seventies, but used the "T" handle of a Philips head T bar. Not only does it restore most butchered heads when you tap the screwdriver back in, it shocks the galvanic bond that forms between the zinc plated thread and the aluminium it's screwing into, which is usually the cause of the head being butchered in the first place.

If that doesn't work it's a munted head and out with the chisel it is. With the correct JIS screwdriver there's no need to whack the shit out the screw. Carb float bowl screws is a perfect example Point is I suppose is most of us blamed the "shit" screws when the screwdriver camed out and that is the end of the screw head. A small dot on the screw head indicates a JIS screw, glad to see I wasn't the only one oblivious to the fact

[skypig]

More info: "The dot indicates JIS" Thanks Lozza

I'm going to be forced to re-evaluate the fact that I know everything. (Maybe now, I know everything. {pesky "unknown unknowns"})

At least I have a reason to buy a few more screw drivers. Where can I buy JIS drivers?

[LWC82PE]

A small dot on the screw head indicates a JIS screw

I thought the dot ment it was a Posidrive

[head]

so how does posidrive fit in the picture.

[Barra]

Posidrive different again.  Cabinet makers know all about 'em.  The screwdriver is like phillips but each internal corner has an extra 'external square rib' instead of the internal radius.  The 'square' ribs fit into corresponding indents in the screw.  Hard to describe, need a picture.

A posidrive screw is identified by a cross line stamped into the head - pretty much like the phillips screw in Lozzas initial post.

Posidrive screwdrivers are also great for butchering phillips screws! And vice versa, but good enough for screwing an appliance against the wall.