Fit Design Analyst TM Glossary of Terms Fit

Fit Design Analyst TM Glossary of Terms

Fit Design Analyst TM Feature

Fit Design Analyst TM Feature - general term applied to a physical portion of a part

Fit Design Analyst TM Feature - general term applied to a physical portion of a part - any observable geometry

Fit Design Analyst TM Feature of Size (FOS)

Fit Design Analyst TM Feature of Size (FOS) - a feature with opposed surface(s)

Fit Design Analyst TM Feature of Size (FOS) - a feature with opposed surface(s) - may be planar or cylindrical

Fit Design Analyst TM Feature of Size (FOS) - a feature with opposed surface(s) - may be planar or cylindrical - is measurable; associated with a size dimension

Fit Design Analyst TM Examples of Features of Size:

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft Planar FOS

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft Planar FOS Internal Planar FOS

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft Planar FOS Internal Planar FOS ………. . … Slot

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft Planar FOS Internal Planar FOS ………. . … Slot External Planar FOS

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft Planar FOS Internal Planar FOS ………. . … Slot External Planar FOS ………. … Tab

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft Planar FOS Internal Planar FOS ………. . … Slot External Planar FOS ………. … Tab The Fit Design Analyst uses the term: TM

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft Planar FOS Internal Planar FOS ………. . … Slot External Planar FOS ………. … Tab The Fit Design Analyst uses the term: TM - “Hole” as an analog to refer to any internal FOS

Fit Design Analyst TM Examples of Features of Size: Cylindrical FOS Internal Cylindrical FOS ………… Hole External Cylindrical FOS ……. . Shaft Planar FOS Internal Planar FOS ………. . … Slot External Planar FOS ………. … Tab The Fit Design Analyst uses the term: TM - “Hole” as an analog to refer to any internal FOS - “Shaft” as an analog to refer to any external FOS

Fit Design Analyst TM Nominal Size

Fit Design Analyst TM Nominal Size - designation used for the purpose of general identification

Fit Design Analyst TM Nominal Size - designation used for the purpose of general identification - usually expressed in common fractions

Fit Design Analyst TM Nominal Size - designation used for the purpose of general identification - usually expressed in common fractions 1 Nominal Size is Ø 2

Fit Design Analyst TM Basic Size or Basic Dimension

Fit Design Analyst TM Basic Size or Basic Dimension • theoretical (ideal) size to which a tolerance is applied

Fit Design Analyst TM Basic Size or Basic Dimension • theoretical (ideal) size to which a tolerance is applied • limit dimensions result from the application of a tolerance specification to a basic dimension

Fit Design Analyst TM Basic Size or Basic Dimension • theoretical (ideal) size to which a tolerance is applied

Fit Design Analyst TM Basic Size or Basic Dimension • theoretical (ideal) size to which a tolerance is applied Basic Dimension Tolerance Specification, applied to the basic dimension

Fit Design Analyst TM Basic Size or Basic Dimension • limit dimensions result from the application of a tolerance specification to a basic dimension

Fit Design Analyst TM Basic Size or Basic Dimension • limit dimensions result from the application of a tolerance specification to a basic dimension Resulting limit dimensions

Fit Design Analyst TM Basic Hole System

Fit Design Analyst TM Basic Hole System • A widely-used fit system employed when standard tools (e. g. , drills, reamers) are used to produce holes

Fit Design Analyst TM Basic Hole System • A widely-used fit system employed when standard tools (e. g. , drills, reamers) are used to produce holes • the small hole (lower limit) is assigned the basic size (typically the nominal size), to which the hole tolerance and fit allowance is applied: “the small hole is basic”

Fit Design Analyst TM Basic Hole System • A widely-used fit system employed when standard tools (e. g. , drills, reamers) are used to produce holes • the small hole (lower limit) is assigned the basic size (typically the nominal size), to which the hole tolerance and fit allowance is applied: “the small hole is basic” • The toleranced shaft size is then designed around the resulting hole limits in order to achieve the desired fit

Fit Design Analyst TM Basic Shaft System

Fit Design Analyst TM Basic Shaft System • A less widely-used fit system typically employed where shafts are purchased in standard sizes or where two or more fits are required on the same shaft

Fit Design Analyst TM Basic Shaft System • A less widely-used fit system typically employed where shafts are purchased in standard sizes or where two or more fits are required on the same shaft • the large shaft (upper limit) is assigned the basic size to which the shaft tolerance and fit allowance is applied: “the large shaft is basic”

Fit Design Analyst TM Basic Shaft System • A less widely-used fit system typically employed where shafts are purchased in standard sizes or where two or more fits are required on the same shaft • the large shaft (upper limit) is assigned the basic size to which the shaft tolerance and fit allowance is applied: “the large shaft is basic” • The toleranced hole size is then designed around the resulting shaft limits in order to achieve the desired fit

Fit Design Analyst TM LIMITS

Fit Design Analyst TM LIMITS • the maximum and minimum sizes indicated by a toleranced dimension

Fit Design Analyst TM LIMITS • the maximum and minimum sizes indicated by a toleranced dimension • called the “upper limit” (large) and “lower limit” (small) dimensions

Fit Design Analyst TM Tolerance

Fit Design Analyst TM Tolerance - the total permissible variation of a dimension

Fit Design Analyst TM Tolerance - the total permissible variation of a dimension TOL = UPPER LIMIT DIM - LOWER LIMIT DIM

Fit Design Analyst TM Tolerance - the total permissible variation of a dimension

Fit Design Analyst TM Tolerance - the total permissible variation of a dimension TOL = UPPER LIMIT DIM - LOWER LIMIT DIM TOL = 1. 006 -. 996 TOL = . 010

Fit Design Analyst TM Maximum Material Condition (MMC)

Fit Design Analyst TM Maximum Material Condition (MMC) • the limit of size of a feature which results in the feature having the maximum amount of material

Fit Design Analyst TM Maximum Material Condition (MMC) • the limit of size of a feature which results in the feature having the maximum amount of material MMCSHAFT = upper limit (large shaft)

Fit Design Analyst TM Maximum Material Condition (MMC) • the limit of size of a feature which results in the feature having the maximum amount of material MMCSHAFT = upper limit (large shaft) MMCHOLE = lower limit (small hole)

Fit Design Analyst TM Least Material Condition (LMC)

Fit Design Analyst TM Least Material Condition (LMC) • the limit of size of a feature which results in the feature having the minimum amount of material

Fit Design Analyst TM Least Material Condition (LMC) • the limit of size of a feature which results in the feature having the minimum amount of material LMCSHAFT = lower limit (small shaft)

Fit Design Analyst TM Least Material Condition (LMC) • the limit of size of a feature which results in the feature having the minimum amount of material LMCSHAFT = lower limit (small shaft) LMCHOLE = upper limit (large hole)

Fit Design Analyst TM ALLOWANCE

Fit Design Analyst TM ALLOWANCE • the minimum clearance (or maximum interference) between mating features

Fit Design Analyst TM ALLOWANCE • the minimum clearance (or maximum interference) between mating features • the allowance represents "the condition of tightest permissible fit" between mating features

Fit Design Analyst TM ALLOWANCE • the minimum clearance (or maximum interference) between mating features • the allowance represents "the condition of tightest permissible fit" between mating features ALLOWANCE = SMALLEST HOLE - LARGEST SHAFT

Fit Design Analyst TM MEAN DIMENSION

Fit Design Analyst TM MEAN DIMENSION • the arithmetic average of the upper and lower limit dimensions

Fit Design Analyst TM MEAN DIMENSION • the arithmetic average of the upper and lower limit dimensions • the mean dimension is used to create geometry in computer-aided design (CAD)

Fit Design Analyst TM MEAN DIMENSION • the arithmetic average of the upper and lower limit dimensions • the mean dimension is used to create geometry in computer-aided design (CAD) • note: the mean dimension is not necessarily equal to the basic dimension

Fit Design Analyst TM End.