The cheaper they are, the greater the difference between crumble and recast. 40k = 18/24hrs, 20k = 10/24hrs, 10k = 8/24hrs, 5k = 4/24hrs.

To determine how much damage they should absorb before premature crumbling, 700 hps * the protection offered by normal sleeks.

I wouldn't allow the minor ABS to be reused while there are timers, but you could allow the major ABS to trump the minors if you wish.

Edges could be created to shrink the crumble differential and improve the crumble damage, and flaws could do the reverse.