On 19/02/2018 4:00 AM, ultred ragnusen wrote:
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 is superior for that application - whether using an
impact driver or not. A 12 point socket is better in situations where
fine motion is required.

This is good to know that the impact socket is superior, probably for two
reasons, right?
1. It has those radius corners (someone said it reduces stress on both the
nuts and the socket itself).

Cracks are more likely to start at a *corner*. That's why crankpins on a
crankshaft have a radius at the fillet. The radius also keeps the impact
forces back away from the very tip of the hex point.

2. It is stronger overall (presumably)

It is thicker and made of a stronger material.

Since there is always a drawback, I think the drawback might be:
3. They're "fatter" it seems, than my normal sockets

They are stronger because they need to be in order to resist the
*impact* forces.

4. They don't seem to come in 12-point sizes (at least mine aren't)

A hex socket is much less likely to round off a nut.

--

Xeno