Powered By Blogger

Monday, April 11, 2011

Descriptive

Manipulating (Rotate) Picture Planes
True*
Size
Shape
Length
Angle

Intersection Points
Distances

True Length Lines
*If the line is parellel to a fold line in one view, it's true length is in the next view.

Point View
*You must first find the true length .
Create a Fold Line perpendiculer to the True Length line

PO = Point
 PD Mode: .96
PD Size: .1

True Size: Surface
Find the TL of one line
Create a Fold line perpendiculer to True Length
Create a Fold Line parellel to egde view

Add-A-Line
Allows you to skip a View and measure back which saves you lots of time instead of doing all the views

Monday, February 28, 2011

Tolerances

It is necessary today to hold precise tolerances to insure the interchangeability of parts
Tolerances:
The process of determining how much a dimension can vary for a part to fit
How accurate is 1/4?
.25
.250
.2507 <---

Basic size  of a rim
Tolerance: Amont of dim varies from basic size.

Feature:
USed to indentify the geometry of the drawing being referred to
-hole
-cut
-extrusion

Limits: The maximum and minimun allowable size

Allowance: Limits where the smallest clearence or largest interference occuring in measurement at MMC

Tolerance style:
Limints dim: Anything in between is good
Plus+Minus Dim: Known as deviation
Symmetrica: Same as +/-
MMC:
Maximum Material Condition
The limit of a dim where the max is left on part
LMC:
Least Material Condition
Least amount of material is left on part

Type of fit:

Clearence:
All dims combinations will produce a clearence

Interferance:
Will create a force fit

Transitional:
Produce different kinds of fit

Wednesday, February 16, 2011

Auxiliary Notes

Secondary View:

TSS (True size and shape) of a surface that shows the forshorted in all traditional views.
***A Surface is TSS when it's egde in the next view is parrellel to the fold line.
*****SKIP A VIEW MEASURE BACK

Monday, February 14, 2011

Dimension Notes

Dimensions:
ANSI
American National Standards Instatute
They decide the standards for all drafting.
Why we dimension:
          Describe
          Locate details
The Big Three Dimensions:
-Width
-Depth
-Hieght

These are the first dimension always applyed while dimensioning a part.
Never apply two of the same dimensions on a drawing especially when you are dealing with three different views.
Always apply them in between views if possible ( Not always possible if dimensions get crowded).

The X, Y, Z
The normal axis points Y being Up/down, X being Side to Side,  and Z being Front to back.

Basic rules:
Make its convinient
No calculations necessary
No Double dimensions

Lines and Dimensions should be:
Lines and symbols inside lines if possible
If not put them outside

Extension:
1/16 in gap
No gap between extension line and center line

Leaders:
Leader scales = dim scale
Circles arch notes
Run at angle to show it's not part of the drawing
Short horizontal 1/4" tail
No Horizontal or Verticle angles
Not thru corners and short as possible

Linear Dims
H/W/D
In between views if possible
Where detail is best described
Don't dim hidden lines
Smallest dim are closest to part
No calculations
No double dims

Angle dims:
Same angle as object being drawn
Use degree symbol (##D)

Circuler dims:
Arc (less then full circle)
Circle use diameter
Arc us radius
Cylander in profile (Where it is best described)
Indicate finished surfaces.