It’s a Conspiracy I Tell Ya!

I wrote this several years ago, but never published it.

Since I just blew out yet another set of hiking shoes and have had to switch to some replacements, it seems appropriate to finally release this post into the wild.

New and watertight (left), old and leaky (right)

I only started wearing the old pair in June of 2024., but, to be fair, I own two sets of footwear. Slippers for evenings on our raw concrete floor and a pair of hiking shoes for everything else, so they do see some wear and tear, everyday, all day.

Not sure the old one on the left can pass the Lincoln-head test anymore

So here's the original, but previously unreleased, post

What’s wrong with this photo?

 On the one hand we have The Van’s tire. On the other we have a set of worn-out hiking boots.

 The tire carries about 2000 pounds. The boot carries about 200 pounds. (When I’m dressed and loaded for hiking) Surprisingly both the tire and the boot have pretty much the same ground-contact area, about 48 sq. inches. Which works out to about 41 pounds per sq. inch for the tire and 4.1 pounds per sq. inch for the boot-sole

The tire has 53000 miles on it. The boot, well let's be generous and say it has as much as 5000 miles on it, although it's probably less.

That means the tire has a total of about 106 million pound-miles on it, or about 148,000 pound-miles per sq. inch (accounting for the circumference of the tire which gives it multibles of 48 sq. inches of ground contact.) The boot sole has total of about 1 million pound-miles on it or about 21,000 pound-miles per sq. inch.

So after carrying about 7 times more load per sq. inch than the boot-sole, the tread depth on the tire is currently at the top of Lincoln’s ear,

 

or about 9.5/32nds of an inch. Well above the 3/32nds safe minimum.

When the tire was new the tread-depth was 12/32nds. That works out to a little more than 21,000 miles per 32^nd of tread-wear.  At that rate there’s another 100,000 miles left in this tire with a comfortable safety margin left over.

Yet, though the uppers are still completely serviceable, after carrying significantly fewer pound-miles than the tire, the boot-soles are completely blown out (in fact they are about to fall off!),

 

and the fancy tread is worn through in places.

That tire cost me about $240. Those boots cost me about $120. Ignoring the 7 times difference in load carried, on just a straight miles per dollar basis I project the tire cost at $1 per 700 miles yet  the boots cost me $1 per 42 miles.

Since both tire and boot-sole are made of molded rubber and rubber-like materials what am I missing here?

Why can’t the boot, which carries so much less load and is rarely slammed into pot-holes and over rocks at 60 miles an hour, deliver better performance?

I smell a boot-maker conspiracy!