AutoCAD 实战讲座

DaShan

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

www.newmaple.com/video/autocad0006

" V1 g4 c3 @0 P/ C/ a4 a1. Title block brief introduction
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2. Text height

3. Viewport
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4. Dimensions style brief introduction
•        Tolerance in Mechanical / Autocad

# g. I/ G1 j1 q; |/ Wspecial symbols
%%D degree sign
%%P plus and minus sign
# z; `+ i; b! J2 F5 ^%%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
4 Z- n3 b; T, U2 ONew Maple AutoCAD (7)
www.newmaple.com/video/autocad0007

A real sample to review lecture 6
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Introduction Roughness
Quick check hole size and position
! L1 P- V: l8 ~6 B% H7 C- CIntroduction O-ring groove

Surface roughness
. [/ d/ ]& K* u" A" k% W' o•        Imperial Unit: micro-inch 10-6 inch
# k5 ^* j1 [* A% z( s•        Metric Unit: micrometer 10-6 m
) ]% m2 x4 t6 G4 R8 h( I0 E- C5 A% r•        Sample 250 micro-inch = 6.3 micrometer
(250X25.4X10-3)
•        250 micro-inch – forging surface
•        125 rough machine, 32 fine machine

Inch size O-ring
. ]# q& [" I  N•        O-ring number 232
•        nominal size 2.75”x3”x1/8”
, ~8 ]6 s9 v: K6 V/ I2 A% r•        Actual size 2.734”x3.012”x0.139”
( ]9 H# W/ A9 @3 q6 r! q' e•        Static surface seal groove depth 0.101~0.107 about 25% squeeze
5 b* i  _2 v1 l2 h/ r) A•        One of OD or ID is close standard size
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http://www.newmaple.com/forumdisplay.php?fid=28