What strength or class nut for steering wheel?
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Tom
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I lost my steering wheel nut, so ordered an M16 x 1.50 jam nut that is marked 04. I've already ordered a factory one, but wondering how cheap and '04' nut is in the meantime? I can find some references online to it, but it generally doesn't show up in the fastener classes for metric nuts. Is it akin to those 4.8 bolts they give you to assemble swing sets, etc.? The 'look' of the factory nut makes me think it's actually a hardened material like 10.9 or 12.9.... Anyone know?
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michaelmount123
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Here you go:
https://www.nord-lock.com/insights/bolt ... 20strength.
No matter what the strength of the nut, it doesn't get a significant load, so I wouldn't worry about it until you get your factory nut. BTW, I've no idea what an MP is, but surely Google does.
https://www.nord-lock.com/insights/bolt ... 20strength.
No matter what the strength of the nut, it doesn't get a significant load, so I wouldn't worry about it until you get your factory nut. BTW, I've no idea what an MP is, but surely Google does.
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Tom
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Well I finally got the factory nut from Stoddard (it was back-ordered apparently) and it is marked 5. Apparently 'thin' nuts have their own ISO & DIN standards, which result in many of them being either 'class' 04 or 05 according to google. 
So the factory uses a class 05 as best I can tell. While normal nuts are marked to correspond to the metric bolt classes (with either a number -- e.g., 5, 8, 10, 12 -- or a hash mark representing where that number appears on the face of a clock), thin nuts have their own classes since they cannot hold as much torque as a regular nut made with the same strength steel. This is all based on 20 minutes of googling, so if there are any mechanical engineers out there who know better, please speak up!
There's a whole world of fastener standards out there. One thing I thought pretty interesting is how the metric 12.9, 10.9, 8.8, etc. labels work. The number before the decimal point is how strong the bolt it before it will break/snap (120, 90, and 80kg of load per square mm, respectively). The number after the decimal represents the percentage of that snapping force the bolt can withstand before 'yielding' and becoming permanently twisted. So a 12.9 bolt can withstand 120kg/mm^2 of load before snapping, and won't get permanently stretched until it reaches 90% of that valve. Who knew.
Here's some light reading on the off-chance any of this is of actual interest to anyone.
https://thomsonrail.com/metric-nuts-and-bolts/
https://www.steelnutbolts.com/sale-1327 ... 3-m53.html
So the factory uses a class 05 as best I can tell. While normal nuts are marked to correspond to the metric bolt classes (with either a number -- e.g., 5, 8, 10, 12 -- or a hash mark representing where that number appears on the face of a clock), thin nuts have their own classes since they cannot hold as much torque as a regular nut made with the same strength steel. This is all based on 20 minutes of googling, so if there are any mechanical engineers out there who know better, please speak up! There's a whole world of fastener standards out there. One thing I thought pretty interesting is how the metric 12.9, 10.9, 8.8, etc. labels work. The number before the decimal point is how strong the bolt it before it will break/snap (120, 90, and 80kg of load per square mm, respectively). The number after the decimal represents the percentage of that snapping force the bolt can withstand before 'yielding' and becoming permanently twisted. So a 12.9 bolt can withstand 120kg/mm^2 of load before snapping, and won't get permanently stretched until it reaches 90% of that valve. Who knew.
Here's some light reading on the off-chance any of this is of actual interest to anyone.
https://thomsonrail.com/metric-nuts-and-bolts/
https://www.steelnutbolts.com/sale-1327 ... 3-m53.html