both fixes Ive seen are pretty good, and I can back myself up when I say that. I am a mechanical engineer and have been in steel structural design for a few years now. I dont know alot yet, but I know enough.
the problem:
repeated loading is occouring (mostly on the weakest axis of the structure) which is changing the chrystaline structure of the steel; a condition known as cold working. over time, this leads to a condition known as fatigue (small cracks), which eventualy leads to failure (damnit, broke another shovel!).
the solution:
I dont have the formulas handy, but heres the deal;
we need to change one or more of the following the axis being loaded, flexing, type of material being coldworked, ammount of material being coldworked, shape of material being coldworked, frequency of cycles, or number of cycles.
lighter dirt aint gonna happen, not digging is out, just stabbing or slicing the ground woulnt work, morpying to titaniun...no., digging one scoop a month is out, digging 5 holes in one scoop is out. doesnt leave much does it?
One of the definitions of Inertia is a resistance to a bending moment. A bending moment can also be thought of as a flexing force, which is occouring every time you take a scoop of dirt. So, to get less loading,flexing, coldwork, fatigue, and damnit, broke another shovel, you need more Inertia! Inertia is made of two things, Mass or volume, and distance. as mass or volume increases, the increase in inertia is ruffly proportional, but as distance increases (width of the cross section) the increase in inertia is exponential. What you did was actualy a little of both: Well Done Gent's!
Installing a rib by bending or pressing one into the metal might have worked also without changing the ammount of material. The height of the rib and not the number of them would produce the most dramatic results (I noticed that the manufacturer did that right up by where the handle meets the blade, which just happens to be where the highest stress concentration is, but what the hell do they know anyways?)
Anyways, Thanks for the chalenge, and rock on <img src="/metal/html/super.gif" border=0 width=26 height=28 alt=":super">
