ADVANCED MECHANICAL DRAFTING LECTURE #23

PROFILE TOLERANCE ZONES PROFILE OF A LINE PROFILE OF A SURFACE

PROFILE OF A LINE Forces a surface to have a profile of some desired shape No datum reference No diameter symbol Cannot be modified Dimensions defining profile shape are basic

Applying Profile of a Line .812 R.005 R.005 + 1.250  1.12 INTERPRETATION .006 WIDE 2D TOLERANCE ZONE .81 ALL DIMENSIONS CONTROLLING THE SHAPE OF THE ZONE ARE BASIC DRAWING

PROFILE OF A SURFACE Forces a surface to have a profile of some desired shape May reference a datum No diameter symbol Cannot be modified Dimensions defining profile shape are basic

Applying Profile of a Surface .812 R.005 R.005 + 1.250  1.12 INTERPRETATION .006 WIDE 3D TOLERANCE ZONE A .81 ALL DIMENSIONS CONTROLLING THE SHAPE OF THE ZONE ARE BASIC DRAWING

DATUM TARGETS Used to define simulated datums on irregular or curved surfaces Exact locations of points, lines, or areas of contact are specified with basic dimensions Datum target symbol Ø.25 A1 Size of contact area (if specifying an area) Contact point identifier

DATUM TARGET POINTS DRAWING INTERPRETATION A1 .25 .50 A .25 .50 A3 A2 DATUM PLANE A LOCATING PINS INTERPRETATION

DATUM TARGET AREAS DRAWING INTERPRETATION C1 Ø.19 .25 .50 C .25 .50 C3 DATUM PLANE C Ø.19 LOCATING PINS INTERPRETATION

DATUM TARGET LINES DRAWING INTERPRETATION F 1.50 F1 A DATUM LINE F F1 LOCATING PIN DATUM PLANE A

LOCATING GSSP MOUNTING HOLES 4X 90º X.XXX ØX.XXX 4XØ.XXX (X/X) THRU .XXX-XXUNC-2B   X.XXX

LOCATING SIDE MOUNTING HOLES 2X X.XXX FOR BOTTOM TAPPED HOLES, MAKE DRILL DEPTH EQUAL THREAD DEPTH 2X X.XXX 4XØ.XXX (X/X)  .XX .XXX-XXUNC-2B  .XX  

LOCATING COVER PLATE MOUNTING HOLES 8XØ.XXX (X/X)  .XX .XXX-XXUNC-2B  .XX   Ø  .XX   .XXX 2X X.XXX X.XXX 2X X.XXX 3X X.XXX Ø  .XX .XXX B

OTHER HOUSING DESIGN CONSIDERATIONS All bores, holes, bosses, etc. (anything cylindrical) must have centerlines Lengths and diameters of bosses must be shown The center hole in the top of the housing must be large enough to clear the top of the yoke while shifting gears The drain hole and filler hole must be located, but may not have to be positioned The lower bearing bore houses a closed-end bearing. A smaller thru hole allows for removal of a worn-out bearing All fillets and rounds must be sized, but this may be done in the title block Define surface finishes where appropriate Add all dimensions necessary to locate and size all features

FINAL EXAMINATION PREVIEW Threads Nomenclature (names of thread parts) Representations (methods of drawing threads) Complete threaded hole callouts Number of threads per inch for given size, form, and series Diameter of thread for a given thread specified by number Required tap drill for given internal thread Required position tolerance for given thread and fastener condition Complete callout for given fastener

FINAL EXAMINATION PREVIEW Threaded Fasteners Screw feature dimensions (head thickness, width, etc.) Matching Match geometric symbols, modifiers, etc. to definitions Feature Control Frames Identify all parts of a typical feature control frame Maximum Material Condition (MMC) Determine MMC of hole and shaft with given dimensions Dimension Types Identify different types of dimensions by appearance Dimension Classes Know the two things that any dimension can do