AutoCAD 实战讲座

DaShan

AutoCAD 实战讲座
; v4 R: w! e# i/ f0 \( B8 Khttp://www.newmaple.com/forumdisplay.php?fid=28

0 L2 v! \/ M  k' |www.newmaple.com/video/autocad0006
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1. Title block brief introduction
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! K0 B8 S5 |( x; F; A$ e& ?4 p2. Text height

3 v$ p; R' `5 k: C9 f8 p: a( K$ W3. Viewport
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# }" l  B; x9 l% Z5 n/ T. f4. Dimensions style brief introduction
% S: q( T  C/ F  d•        Tolerance in Mechanical / Autocad
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! a1 B5 ]2 n7 g) k  R; W' especial symbols
%%D degree sign
%%P plus and minus sign
%%C diameter symbol

恭喜发财

爱城飞雪

Very practical!

DaShan

[V] AutoCAD 实战讲座第七讲
AutoCAD 实战讲座第七讲
New Maple AutoCAD (7)
www.newmaple.com/video/autocad0007
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A real sample to review lecture 6

Introduction Roughness
* z3 l& q: F3 {* DQuick check hole size and position
" z8 u0 S/ O/ ?" D" S# l9 l) qIntroduction O-ring groove

, V" l, l& i8 L- OSurface roughness
+ f* i4 c! t: Q5 Q•        Imperial Unit: micro-inch 10-6 inch
6 ^0 f# F4 C+ |" h+ }( [+ A3 I•        Metric Unit: micrometer 10-6 m
. \0 r4 f3 t' C5 d! A9 O•        Sample 250 micro-inch = 6.3 micrometer
(250X25.4X10-3)
' k  N1 T; Y# m0 s•        250 micro-inch – forging surface
: H. C  ~8 ]1 u; Y) o' Y•        125 rough machine, 32 fine machine

Inch size O-ring
•        O-ring number 232
•        nominal size 2.75”x3”x1/8”
7 R3 m7 F2 u6 l; i! v* X; l$ w•        Actual size 2.734”x3.012”x0.139”
•        Static surface seal groove depth 0.101~0.107 about 25% squeeze
! B: Y. X- Z8 Q+ X•        One of OD or ID is close standard size
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http://www.newmaple.com/forumdisplay.php?fid=28