AutoCAD 实战讲座

DaShan

AutoCAD 实战讲座
http://www.newmaple.com/forumdisplay.php?fid=28
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( d( s3 I: {9 ~www.newmaple.com/video/autocad0006
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1. Title block brief introduction

: J7 U0 X7 J. E# u1 o2. Text height
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3. Viewport
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' T: ^: O( J0 U: z* f0 v+ Y0 l4. Dimensions style brief introduction
$ r6 s1 Z/ _, f" b" [) O- K•        Tolerance in Mechanical / Autocad
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# K* m  D% t! t3 f' U2 n5 P: V; Ospecial symbols
%%D degree sign
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%%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
0 r" _5 e5 Q6 G6 U) r6 JNew Maple AutoCAD (7)
www.newmaple.com/video/autocad0007

A real sample to review lecture 6
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Introduction Roughness
- u6 w( N4 ]: |- g! j9 BQuick check hole size and position
Introduction O-ring groove

Surface roughness
) Z5 D1 L2 S0 r5 W•        Imperial Unit: micro-inch 10-6 inch
•        Metric Unit: micrometer 10-6 m
) t9 A7 K; T* c  p•        Sample 250 micro-inch = 6.3 micrometer
7 \6 A* [0 T( L* w/ B0 X(250X25.4X10-3)
•        250 micro-inch – forging surface
8 H3 Z3 r6 F: L# y•        125 rough machine, 32 fine machine
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& K& Z5 x3 G' l& U. A8 yInch size O-ring
* s$ i, K4 L4 n# o! x•        O-ring number 232
•        nominal size 2.75”x3”x1/8”
•        Actual size 2.734”x3.012”x0.139”
•        Static surface seal groove depth 0.101~0.107 about 25% squeeze
9 g# U! l+ A6 ^. M•        One of OD or ID is close standard size
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http://www.newmaple.com/forumdisplay.php?fid=28