Bolt Strength Advice - Please

I am doubtful that they will be strong enough, but this just my gut reaction. A normal M12 hex nut is 19 mm across the flats, giving a wall thickness of 3.5 mm. Obviously there is going to be a margin of safety built in when M12 hex nuts are used as wheelnuts, but you want to keep that margin of safety. The behaviour of the nut and how it might fail will be pretty complex, so a calculation would not be straightforward.

Best wishes,

Chris Tidy

This would reduce the cross-sectional area to about 44% of what it was, almost equivalent to running with only 2 bolts present in a

You'd increase the stress in the bolts by a factor of 2.29. That sounds dicey to me, though there is surely a significant safety factor in the original design.

I have had some bad experiences with stainless nuts and bolts. I am wondering if there will be metal pickup problems using stainless in a situation where the fastener will be used repeatedly. Randy

My concern is not knowing whether the aproximately 2mm wall thickness of material left will be sufficiently strong enough. The intended use is on a 'show' car but will be driven (carefully) on the road.

I would not know where to start calculating, and even if I could I would not know the values of whatever forces are involved.

Any comments would be appreciated.

Ian Phillips

Make one and apply a cross-pattern lug wrench to it.

I'll lay even odds that you can snap the head right off without half trying.

Jim

these can be bought pretty readily, as such you would be better off making completely from scratch and heat treating

Why not two sets. One "show" set and one higher strength one for driving the car on the road. Better safe than dead or trashed car. Of course sooner or later they're going to drive with the show set. Karl

Don't forget the reduction is cross section is in the least stressed area at least as far a torsion goes. Also, don't forget that the remaining cross section is the highest strength portion due to the work hardening effect of stainless steel.