Per the patch notes:
Mad Tinkerer:
Increased the damage of this set to 10390, up from 9999.
Removed the proc chance from this set. Whenever you deal damage, a verminous fabricant will be summoned that will charge the nearest enemy, doing 10,206 damage.
Reduced the cooldown to 8 seconds, down from 10.
However, in the game, the item set has not changed at all.

Thanks!
Toro