Consider a hole H whose diameter is bounded by a lower bound

Consider a hole H whose diameter is bounded by a lower bound phiH_m and an upper bound phiH_M. Define the two following expressions.

1. Max material condition of the hole.

2. Minimum material condition of the hole.

Solution

MMC is the condition contains the maximum amount of material, that is, the smallest hole or largest pin, within the Tolerance. LMC is the condition in which there is the least amount of material, the largest hole or smallest pin, within Tolerance.

MMC defines the worst case condition of a part that will still guarantee, because it is still within the mentioned tolerances, the assembly between pin(s) and hole(s). When a hole is at its smallest (MMC) and a pin is at its largest condition (also MMC), we can be sure that we will still be able to assemble that part. Thus, MMC is widely used in cases where clearance fits are common..

Whereas,

Least material condition refers to a feature of size containing the least amount of material, yet remains within its tolerance zone:

In Industries Least Material Condition, as its cost less and also fullfills the requires mating assemble.