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buggered phillips screws?

PostPosted: January 6th, 2015, 10:39 am
by grumpyvette
We all have one or more Philips head screw drivers in our tool boxes. It's pretty much impossible to be a DIY'er without them. But, if you own an a vehicle that was manufactured of Asian origin, chances are, the screws on it are not "standard" Phillips head. So, if you find that your Phillips head screw drivers are ruining your fasteners, it very well might be because you're using the wrong tool for the job. this use of the wrong matching tool for the screws,will result in stripped screws and damaged screw drivers

Lesser known is the Japanese Industrial Standard (AKA JIS). Bottom-line, a standard Phillips driver will not go into a JIS screw all the way because the corner radius of the screw is smaller than that of a standard Phillips driver. Because of this, it leads to what is referred to as "cam-out". In fact, the standard Phillips was created to allow this, so that you know when max torque has been reached, avoiding over tightening or worse, snapping fasteners.
A little known, but 'troublesome' standard, the Japanese Industrial Standard (JIS for short) is a Pacific Rim phenomenon. You can never tell where you will find it now - it's everywhere. But start with the Pacific Rim: anything of Asian origin is almost certainly going to include it. The symptom of the problem is when your standard Phillips screwdriver 'hangs up,' and doesn't feel quite right. The Phillips driver won't go into the JIS Screw all the way because the corner radius of the screw is smaller than that of the Phillips scredriver! This is the primary cause of what we know as 'cam-out.'

Oddly enough, the Phillips standard was created to allow this condition so that you knew you had reaced maximum torque!

We carry two major brands of JIS Screwdrivers in a variety of formats. Moody Tools, Inc. is Made in Rhode Island. Vessel Tools are made in Japan. We have Moody Tools and Vessel listed separately as well, but this section just concentrates on JIS..

The differences between Phillips and JIS are not easily seen, so this illustration should help.

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Sometimes screws will be identified as being JIS if there is a dimple or dot on its head. But, this isn't always the case. But chances are, if you're working on a Japanese machine, the Philips head screws will be JIS.
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JIS screw drivers are not hard to find, ranging in price from the mid to high $20.00 for the budget stuff, on up to 3x (or more) that for the good stuff. Good tools, if taken care of can last a lifetime and the right tool for the job saves time and money in the long run.
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http://www.rjrcooltools.com/shop_item_d ... cat_ID=138

Re: buggered phillips screws?

PostPosted: January 6th, 2015, 11:37 pm
by philly
holy crap my mind has just ben blown, that is easily the most important thing ive learned in 2015

Re: buggered phillips screws?

PostPosted: January 7th, 2015, 9:45 am
by grumpyvette
yeah! I figured most guys did not know that so I figured I,d post the info just in case anyone was UN-aware of that little difference in design

Re: buggered phillips screws?

PostPosted: January 8th, 2015, 7:48 am
by DorianL
grumpyvette wrote:yeah! I figured most guys did not know that so I figured I,d post the info just in case anyone was UN-aware of that little difference in design


Oh Hell yeah! I was completely unaware of that one.