I have a collection of odd bolts and machine screws for odd jobs. The threads of holes and nuts come in different diameters of inches or millimeters and different pitches. Matching with the right coarse or fine, US or metric bolt can be daunting.

Now if the bolt threads were made like a stiff coiled spring, it could adjust to a small range of diameters and pitches while still possessing a minimum strength.
-- FarmerJohn, Feb 24 2005

(?) Springbok http://www.namibweb.com/springbok.JPG
[normzone, Feb 24 2005]

Sounds like a great innovation. But would there be a mechanism for securing the movable thread or would it be just rigid enough to resist movement when fitted to the nut?

Is there a way this could address the thickness of thread as well as the gradient?

(Later: Well that answers my points, go nuts with a bun.)
-- Jinbish, Feb 24 2005


[Jb] I was thinking rigidity but [UB]'s suggestion seems superior.
-- FarmerJohn, Feb 24 2005


I would hardly call it fully baked, being a hole thread repair kit, not an adjustable bolt.
-- FarmerJohn, Feb 25 2005


Which properties of a bolt would this new gizmo retain, other than filling the thread portion of a threaded hole?

If it has some sort of solid core, I can see it providing some resistance to shearing forces across the diameter. Maybe you're considering tiny little applications that don't require a lot of tensile strength.

The "Helicoil" thread repair device is exactly what I thought of when I first read this.
-- half, Feb 25 2005


The spring bolt needn’t be as hollow as the Helicoil. Think of a solid bolt cut to the middle (axis) by a helical slice. Of course the bolt would have a limited strength, that could be improved by injecting an bonding agent.
-- FarmerJohn, Feb 25 2005



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