AutoCAD 实战讲座

DaShan

AutoCAD 实战讲座
http://www.newmaple.com/forumdisplay.php?fid=28
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9 d# j2 e, s) ?www.newmaple.com/video/autocad0006

9 [4 ~+ W5 K* a0 f) k+ _# x9 v1. Title block brief introduction
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2 `  e( B1 Y' E' ], t; h& t7 @2. Text height

3. Viewport
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4. Dimensions style brief introduction
4 _1 L* a1 v' ^  A•        Tolerance in Mechanical / Autocad
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. B# W) Y6 f( X: S( R" `special symbols
%%D degree sign
%%P plus and minus sign
; _4 i  W% V8 X%%C diameter symbol

恭喜发财

爱城飞雪

Very practical!

DaShan

[V] AutoCAD 实战讲座第七讲
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New Maple AutoCAD (7)
www.newmaple.com/video/autocad0007
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: {! M& z0 p$ kA real sample to review lecture 6
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' [) S$ P* F3 O4 ?$ \/ Q& ^Introduction Roughness
Quick check hole size and position
Introduction O-ring groove

Surface roughness
" y2 a. M4 P& h•        Imperial Unit: micro-inch 10-6 inch
•        Metric Unit: micrometer 10-6 m
! N( c! L, s! ^•        Sample 250 micro-inch = 6.3 micrometer
(250X25.4X10-3)
. k( }& G& p3 H3 a" |•        250 micro-inch – forging surface
•        125 rough machine, 32 fine machine
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Inch size O-ring
•        O-ring number 232
  l3 q7 u! Q, W8 g* T•        nominal size 2.75”x3”x1/8”
# Y4 M7 L+ l$ m•        Actual size 2.734”x3.012”x0.139”
5 y" G- O$ V" Z0 B•        Static surface seal groove depth 0.101~0.107 about 25% squeeze
•        One of OD or ID is close standard size

6 W/ T8 O! i% r+ ^; q% hhttp://www.newmaple.com/forumdisplay.php?fid=28