AutoCAD 实战讲座

DaShan

AutoCAD 实战讲座
. v! l  r% Y/ i( n! p- f9 rhttp://www.newmaple.com/forumdisplay.php?fid=28

www.newmaple.com/video/autocad0006
3 r& j( t$ ?6 H1 g, Y/ n/ ]  i
1. Title block brief introduction

+ X) Z5 @# d) s6 V) z" v9 M( s* Z2. Text height
* {. z$ p3 h& e. O
6 ]& K# n6 G0 N' a3. Viewport
, e% _  t& j) l% f+ [* e& h& s
# F& F0 L" {( l$ F4. Dimensions style brief introduction
•        Tolerance in Mechanical / Autocad
; l+ f3 _1 w# D, |$ ^
special symbols
6 |  m# B! u6 x8 W2 F. _# T%%D degree sign
: n: ~: E. S- p6 T! Y9 x6 m%%P plus and minus sign
' S. }' j+ a; ?# Y4 M+ W%%C diameter symbol

恭喜发财

爱城飞雪

Very practical!

DaShan

[V] AutoCAD 实战讲座第七讲
9 F7 q& }. P$ }! m* E9 KAutoCAD 实战讲座第七讲
2 c/ R# ~+ W/ j7 sNew Maple AutoCAD (7)
% ]* H. I) s- k3 l+ Awww.newmaple.com/video/autocad0007

A real sample to review lecture 6

Introduction Roughness
Quick check hole size and position
- V# r9 r8 ]- S: p( zIntroduction O-ring groove
3 G( x9 t& D' q* g' O2 I
Surface roughness
•        Imperial Unit: micro-inch 10-6 inch
+ h4 D; F% \6 B5 [3 K•        Metric Unit: micrometer 10-6 m
•        Sample 250 micro-inch = 6.3 micrometer
! e6 q8 \1 j. k) |( J+ A(250X25.4X10-3)
•        250 micro-inch – forging surface
! m% `6 d2 v2 b% R•        125 rough machine, 32 fine machine
4 T5 n5 q$ Y' Q9 w$ C& R5 Y+ O
Inch size O-ring
•        O-ring number 232
( _: i. s* H+ _" D# O' S9 F0 i•        nominal size 2.75”x3”x1/8”
$ i5 W" r. c( K$ p9 w- i4 D•        Actual size 2.734”x3.012”x0.139”
; W( g4 b0 p) E0 j) E. _•        Static surface seal groove depth 0.101~0.107 about 25% squeeze
& G; m' r% J, [( g7 p! y6 ^! u: v•        One of OD or ID is close standard size

  V/ d- W7 {5 Z' I4 k  H5 [) [http://www.newmaple.com/forumdisplay.php?fid=28