Limits, MMC, LMC
How do I figure out what the MAX. and MIN. limits to drawing a part are? Is there a specific way? Also how about tolerances and MMC and LMC
First maximum material condition (MMC) is the highest limit of material of a part to flow to attain its maximum weight limit.
Whereas least material condition (LMC) is the highest limit of material to flow to attain its minimum weight limit.
Consider a solid shaft with diameter 20mm, with tolerance of +-0.2mm (i.e.: 20+-0.2mm).
MMC of this shaft is 20.02
And LMC is 19.8
But. The mmc and lmc of hole is different.
If you consider a hallow cylinder of inner diameter 10mm, with tolerance 0.2mm (i.e.: 10+-0.2)
Here mmc of shaft is 9.8mm
Lmc is 10.2mm.
Think physically a little bit.
If the diameter of hole increases. That means the material is removed. Like as if you drill a hole to wall and the concrete is removed.
If decrease the dia of the hole. The material is added, in the free space.
This can help with illustrations http://atilim.edu.tr/~ie205/Geometric-Dimension-Ing-Tolerancing-Part2.pdf