AutoCAD 实战讲座

DaShan

AutoCAD 实战讲座
- R) j0 O4 h; V- `  Uhttp://www.newmaple.com/forumdisplay.php?fid=28
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; r( S6 P: R9 U4 }# gwww.newmaple.com/video/autocad0006

1. Title block brief introduction
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/ |0 K4 m2 F+ m0 H! }- p( B" |1 a/ N2. Text height

% K6 r0 J7 |: W3 X" _3. Viewport
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- H. B# [% m3 G% n" {# z' L4. Dimensions style brief introduction
% E7 g3 r1 `5 f' `$ l•        Tolerance in Mechanical / Autocad
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; W8 P  U; W0 H( y. f) Mspecial symbols
%%D degree sign
1 y7 W6 K2 |+ w, J4 }5 x6 l. O%%P plus and minus sign
" K4 T8 k+ E! V/ A9 P3 f+ A% f6 X%%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
; V$ g; q6 I7 W( h, RNew Maple AutoCAD (7)
www.newmaple.com/video/autocad0007

A real sample to review lecture 6

Introduction Roughness
, f3 a% u3 T9 B1 V* ~0 }( y5 MQuick check hole size and position
Introduction O-ring groove

- D: ^+ ~6 N% q7 K# W1 Q) YSurface roughness
3 A& D3 U+ R& |4 ~  T•        Imperial Unit: micro-inch 10-6 inch
•        Metric Unit: micrometer 10-6 m
$ r4 k1 d1 a$ F1 W•        Sample 250 micro-inch = 6.3 micrometer
) Z& X4 U3 J) t. W- ~$ v(250X25.4X10-3)
4 I& H, }& O: e9 G, s) B•        250 micro-inch – forging surface
•        125 rough machine, 32 fine machine
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% f% V7 y$ [- |8 z/ Q. W- \Inch size O-ring
•        O-ring number 232
5 m8 J# y+ H0 p0 S6 P8 d0 {•        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
) L5 y2 |' [1 [0 M' [$ @+ f" F& a•        One of OD or ID is close standard size

5 K5 w, |/ M2 `% M: }http://www.newmaple.com/forumdisplay.php?fid=28