AutoCAD 实战讲座

DaShan

AutoCAD 实战讲座
http://www.newmaple.com/forumdisplay.php?fid=28
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www.newmaple.com/video/autocad0006

" U% h0 ]1 n: x5 s  u& N1. Title block brief introduction
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$ h  K7 y/ E1 f) [9 A" }3 `2. Text height

& Z( O) t' c& N0 ~' P' s3. Viewport
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3 Y2 {3 M( T, T) k4. Dimensions style brief introduction
•        Tolerance in Mechanical / Autocad
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8 J! V, N& R+ Z& G, Fspecial symbols
2 x3 O% O$ A! M5 V%%D degree sign
: U. w6 Y% u4 [- X" g; k0 A%%P plus and minus sign
8 Q! L3 v- ~5 U% c9 V%%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
7 ~% S: w1 W. [2 W8 l: {" PNew Maple AutoCAD (7)
www.newmaple.com/video/autocad0007
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+ m8 {, Q  o. N5 tA real sample to review lecture 6
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Introduction Roughness
Quick check hole size and position
3 e2 M* i/ ]" YIntroduction O-ring groove

Surface roughness
$ v7 f3 ^* Y$ ~/ [•        Imperial Unit: micro-inch 10-6 inch
8 t  l9 o% R9 d- I  D! F# n•        Metric Unit: micrometer 10-6 m
2 R$ T! E$ l7 F5 u•        Sample 250 micro-inch = 6.3 micrometer
(250X25.4X10-3)
9 J; d; y7 J9 |: f3 j. B* c•        250 micro-inch – forging surface
  E/ ^4 G2 G+ O. A3 U+ S•        125 rough machine, 32 fine machine
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Inch size O-ring
: V' v' k; o8 C/ @. v5 e/ |! p•        O-ring number 232
•        nominal size 2.75”x3”x1/8”
2 r- a. a/ ]$ s9 G•        Actual size 2.734”x3.012”x0.139”
•        Static surface seal groove depth 0.101~0.107 about 25% squeeze
( B& M6 D' M+ z* I' R6 l+ s" O3 x' K•        One of OD or ID is close standard size
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http://www.newmaple.com/forumdisplay.php?fid=28