springer3

I don't know. Soft bolts have much greater plastic elongation at break than stronger grades. I suspect either loads are not great enough to justify a high-strength bolt, or perhaps they wanted the greater elongation-at-rupture characteristics. Bolts can be designed to control failure mode, and perhaps the factory needed for the seat bolts to break before something more critical.

I know all about rounding out the socket-head and having to drill the *&^%$# things out.

springer3

Wow - did you get to the part about the counterfeit bullet-proof vests?

Almost all the counterfeit bolts in the 1990s scandal were manufactured in Japan. In their defense, the Japanese factories did not understand the SAE and ASTM grade marks. They filled orders from unscrupulous suppliers who requested the marks on bolts meeting lower grade standards.

Listing a head mark on the USPTO fastener registry simply means they registered. It does not imply the Government or anyone else has verifyed they provide bolts that meet the requirements for their grade markings. It is still pretty much caveat emptor in the bolt business.

elbeee964

That's sounding suspiciously like the the old I'd-rather-be-thrown-clear school of seat bolt design.

And, ahhh, if ya need me, springer, I'll be over here... in the Jesus-please-keep-my-seat-bolts-unbroken corner of the room.


(And I feel yer pain, brother, in rounding out one of those factory seat socket heads -- &%$#%!!!)

MisterRisky

I'm not so quick to throw out Springer's idea. If you look at the bottom of your seatbelt, underneath the plastic shroud, you will see our seatbelts are designed to rip out stitching prior to fully loading the webbing. This "rip cord" design basically slows the moving meat down some prior to the webbing taking the rest of the load. It's both easier on the person and puts a lower load on the belt webbing if the stitching can fail gracefully and then load up the seat belt. This is sort of the "controlled failure" that Springer talks about.

Honestly though, I can't come up with a good reason not to use the strongest bolt possible when holding the seats down.