Screwfix Prices Then And Now

[Harry Bloomfield]

I think there's a Japanese cross-head that's probably used in China a lot. It's just the same but different, and just compatible enough to make you think it fits, then you chew the head off the screw.

JIS ? They like a phillips, but with a single dot at one point of the head.

 

[robinbanks]

I wonder whether the cross-head screws and driver I mentioned a short while ago are actually JIS types.
If they work as well as they sound, it might be a good idea for us all to adopt the Japanese type

Pozi, Philips and JIS screws all work very well when driven with a matching bit in good condition

The problem is people tend not to appreciate that there are differences, and think that "a cross head is a cross head" and drive them with the wrong bits, ruining the screw and the bit and making it more likely that problems will arise when driving subsequent screws with the same bit

 

[JBR]

Pozi, Philips and JIS screws all work very well when driven with a matching bit in good condition

The problem is people tend not to appreciate that there are differences, and think that "a cross head is a cross head" and drive them with the wrong bits, ruining the screw and the bit and making it more likely that problems will arise when driving subsequent screws with the same bit

Yes, that is perfectly logical and I agree completely.
On the same basis, I shall stick with Torx as the screws and the bits (several sizes) are certain to be used with each other as they bear no relationship to cross-head screws, so I'm unlikely ever to use the wrong ones!

 

[robinbanks]

Sound logic

Side bar, it's typically quite clear, visually, whether a screw head is Pozi, Phillips or JIS..

This is Phillips/Pozi; Pozi is a more aggressive sounding word and the bit/screw looks more aggressive too (is how I remember it):

JIS screws look like Phillips with a single dot on.

The difference between JIS and Phillips bits is more subtle; thankfully JIS are relatively more rare, but the pivotal difference in terms of ruining screws is this pink highlighted angle:

Using a Phillips bit in a JIS screw usually means the screw hole isn't deep enough to fit the bit, so bit only gets minimal purchase on the centre of the +, rounding it out