There are a few. The most common are break away bolts where the head breaks off when it’s torqued. But those require special steps to remove which makes them poorly suited for many regularly serviceable items. Plus cost. Believe it or not special fasteners can get expensive quick. Plus such bolts need to have tight manufacturing specs. Not suited to the mass production volume of many common fasteners.
Another common one are “low torque” heads like types of slotted screw or “Allen” type heads in small sizes. They tend to be most available in small hand tools and the size and shape give you a large chance of “rounding” or “jumping out” of the slot ifyou apply too much torque for the shank. Of course, you can still damage whatever you’re joining if it’s fragile like plastic.
There are also bolts with a rubber section (increased cost, decreased production volume, more frequent servicing and one time use or needing replacement by time in service) which are illsuited to many consumer applications. And special “torque rods” or “dummy sticks” exists for power tools which have a metal composition which flexes to absorb torque instead of the bolt and prevent over tightening. .
The thing about those last two is they aren’t precise or consistent- meaning they get in a range close to the desired maximum torque- so those are poorly suited to precise operation, and if you use WAY too much physical force or a powerful tool you can still overtorque and damage the fastener or tool.
Plus the sizes and torque specs on bolts are all over the place based on application. So the maker needs to create a wide range of sizes and torques for each and deal with logistics, while in order to have them handy to use the user must stick a large and diverse supply as well. So cost is the main factor when a manual and a single torque wrench will allow anyone with any business working on the thing to hit the right torque 99% of the time and use any generic fastener more or less that fits.
This all reminds me of an article I read about a month or two ago about on the bolts NASA uses and plans to use (particularly on the SLS)... and just how fucking insane the testing is. They are only going to be producing a few thousand of those bolts, max, but the testing and the specially designed equipment needed to properly test them costs a few tens of millions.
It’s no joke. Lol. After studying engineering and getting some time machining I had a healthy respect for fasteners, but I worked on some projects with some guys who are full time fastener engineers. There’s so much to it, especially in speciality and critical applications. Wish I could say I learned some lessons, but I still practice my philosophy which horrified them with fasteners: “If it fits it sits!”
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