wrote:

>> First question is what is the practical difference between these three 21mm
>> (13/16ths) "sockets" for the lug bolts on the car I was working on today?
>> http://wetakepic.com/images/2018/02/17/socket_ends.jpg
>> 1. The standard lug wrench (green) has 6 points, each at a sharp angle.
>> 2. The impact socket (black) has 6 points, each at a semicircular angle.
>> 3. The standard socket (chrome) has 12 points, each at a sharp angle.
>
> The impact socket has a radius at the points to remove the stress
> concentration that would split the socket when used with impact tools.
> It also contacts the nut on the strong flank and not the weak point.

That makes sense! So the rounded corners take the 'stress' off the nut and
the rounded corner also takes the stress off from the potential for a
hairline crack of the socket wall?

> A full hex is better than a 12 point for nearly all uses.

I was wondering if a 12-point is "weaker" than a 6 point?
Is at 6 point stronger, weaker, or the same stress on a nut/socket as a 12
point?

> You can always
> rotate the socket 1/4 turn on the 1/2" drive to get 12th of a turn when
> space to swing the bar is tight.

I never thought of that!
The math confused me so may I reiterate what I "think" you just said?

Am I correct in assuming you're saying that you can rotate a 12-point
socket by 1/12th, while you can only rotate a 6-point socket by 1/6th ---
but ... if you cleverly rotate /both/ the 6-point socket by 1/6th and the
half-inch socket wrench end of the socket by 1/4, you get the same effect?