Originally Posted by mander
Off the top of my head I guess that not-very-hard stampin' steel, ****ty tolerances for thread cutting, and lower overall threaded surface area are to blame, but maybe someone else knows for sure.
I can't remember my hardness tables from chemistry class, but any steel at all has to be harder than aluminum, and if it was softer, you'd strip the cog threads, not the ones on the hub.
Phil cogs definitely are impressive in their machining, beautiful even, and the threads "look" thick, but any cog that you easily screwed on and doesn't have any side to side play while it's on has to have enough threaded surface to engage the hub threads. Tolerances on machined, forged, or stamped parts will be to the hundredth or thousandth of an inch, and we're talking about something that should never move at all if it's installed correctly.
I'm just throwing that out there, I'm not a machinist or anything, and I certainly won't say that cheaper stuff is as good as more expensive and better made stuff, but this is one of the most popularly repeated things in this forum, that cheap cogs kill hubs, and I just don't get it. I've never used one, but my Somas were accused of being crummy on this forum, and they're infinitely better made than the generics I've seen in shops, but functionally they don't look so different.