| |
Structures
and Mechanisms Subsystem
Purpose:
this
subsystem includes the hardware (structures) in order to hold and
contain the craft and protect it from its environment. It also
involves the hardware (mechanisms) required to deploy, move, or rotate
sensors, payloads, power-systems, etc. in order to perform their
function or protect them from harm.
Boe-Bot
Chassis: From
Andy Lindsay's Robotics with
the Boe-bot
Screw
Dimensions
|
We
have listed our screw dimensions in two forms a table
showing the maximum and minimum decimal dimensions, and a
table showing the maximum fractional dimensions. Note: The
fractional dimensions are the best approximations of the
actual decimal dimensions.
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|
|
|
A
Flat Head
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A
Pan Head
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A
Round Washer Head
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A
Truss Head
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|
Size
|
max
|
min
|
max
|
min
|
T
max
|
max
|
min
|
T
max
|
max
|
min
|
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4
|
0.225
|
0.195
|
0.219
|
0.205
|
0.086
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N/A
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N/A
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N/A
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N/A
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N/A
|
|
6
|
0.279
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0.244
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0.270
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0.256
|
0.103
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N/A
|
N/A
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0.086
|
0.321
|
0.303
|
|
8
|
0.332
|
0.292
|
0.322
|
0.306
|
0.120
|
0.376
|
0.352
|
0.102
|
0.384
|
0.364
|
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10
|
0.385
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0.340
|
0.373
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0.357
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0.137
|
0.443
|
0.411
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N/A
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N/A
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N/A
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|
12
|
0.438
|
0.389
|
0.425
|
0.407
|
0.153
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N/A
|
N/A
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N/A
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N/A
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N/A
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|
14
|
0.507
|
0.452
|
0.492
|
0.473
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0.175
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N/A
|
N/A
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N/A
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N/A
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N/A
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Corresponding
Fractional Measurements
|
|
A
Flat Head
|
A
Pan Head
|
A
Round Washer Head
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A
Truss Head
|
|
Size
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Approx.
Dia
|
Approx.
Dia
|
T
max
|
Approx.
Dia
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T
max
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Max
|
Max
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4
|
7/32
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7/32
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3/32
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N/A
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N/A
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N/A
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N/A
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6
|
9/32
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17/64
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7/64
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N/A
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3/32
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21/64
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5/16
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8
|
21/64
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21/64
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1/8
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3/8
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7/32
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25/64
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23/64
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10
|
25/64
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3/8
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9/64
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7/16
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N/A
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N/A
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N/A
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12
|
7/16
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27/64
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5/32
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N/A
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N/A
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N/A
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N/A
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|
14
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1/2
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31/64
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11/64
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N/A
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N/A
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N/A
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N/A
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B
Body Dia
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C
Thread Dia
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Size
|
max
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min
|
max
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min
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4
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0.095
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0.084
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0.116
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0.105
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6
|
0.118
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0.107
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0.142
|
0.131
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8
|
0.136
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0.125
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0.168
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0.157
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10
|
0.157
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0.146
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0.194
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0.183
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12
|
0.176
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0.165
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0.220
|
0.209
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14
|
0.201
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0.190
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0.246
|
0.235
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Corresponding
Fractional Measurements
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B
Body Dia
|
C
Thread Dia
|
|
Size
|
T
max
|
Max
|
Max
|
|
4
|
N/A
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3/32
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1/8
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|
6
|
N/A
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1/8
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9/64
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|
8
|
7/64
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9/64
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11/64
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|
10
|
1/8
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5/32
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3/16
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|
12
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N/A
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11/64
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7/32
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|
14
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N/A
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13/64
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1/4
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Screw
Length
Screw
lengths are measured differently depending on head type and their
intended application.
-
Flat
head and Trim head screws are designed to be countersunk into the
surface. These screws are measured from the top of the head.
-
Pan
head and Round Washer head screws are designed to have the head
sit on top of the surface. These screws are measured from beneath
the head.
Overall
Length and Thread length Specifications:
|
Overall
Length
|
|
|
|
Nominal
Screw Length
|
Tolerances
|
|
|
Plus
|
Minus
|
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Up
to 5/8"
|
0
|
0.030"
|
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Over
5/8" to 1"
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0
|
0.050"
|
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Over
1" to 1-1/2"
|
0
|
0.050"
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Over
1-1/2" to 2-3/4"
|
0
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0.060"
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Over
2-3/4"
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0
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0.090"
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|
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Thread
Length for Flat and Trim Head (unless specified otherwise)
|
|
under
1"
|
Full
Thread
|
|
1"
and over
|
2/3
Thread
|
|
*
Note: Tolerance on thread length of 3" and longer screws
is 2/3 + or - 1/4"
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|
Thread
Length Pan Head (unless specified otherwise)
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All
sizes
|
Full
Thread
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Machine
Screw Dimensions
Need
dimensions? Weve got em right out of the Industrial
Fasteners Institute Fastener Standards, Sixth Edition! If all you want
to do is determine what size fastener you have, might I suggest our
nifty thread gage (DG-0014) instead? Its a lot easier!
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|
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Length
Tolerance
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Up
to and Including 3/4"
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-.03"
|
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Over
3/4", up to 1-1/2" Included
|
-.05"
|
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Over
1-1/2"
|
-.06"
|
|
Size
|
A
Flat and Pan
|
B
Flat Head
|
B
Pan Head
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C
Pan Head
|
|
Max
|
Min
|
Max
|
Min
|
Max
|
Min
|
Max
|
Min
|
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6-32
|
.137
|
.131
|
.279
|
.244
|
.270
|
.256
|
.097
|
.087
|
|
8-32
|
.163
|
.157
|
.332
|
.292
|
.322
|
.306
|
.115
|
.105
|
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10-24
|
.189
|
.181
|
.385
|
.340
|
.373
|
.357
|
.133
|
.122
|
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10-32
|
.189
|
.183
|
.385
|
.340
|
.378
|
.357
|
.133
|
.122
|
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1/4-20
|
.249
|
.236
|
.507
|
.452
|
.492
|
.473
|
.175
|
.162
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To
convert the decimal dimensions shown above to fractional dimensions,
simply multiply by 64. The result will be the number of 64ths of an
inch equal to the decimal dimension. For instance, the thread size on
a 1/4-20 screw is given as .249". Converting to a fraction,
multiply by 64 (.249 x 64 = 15.936). The answer, 15.936, rounds to
16/64, or 1/4 of an inch. McFeelys
Metric Conversion Chart
Lifting
Strap
http://www.mcmaster.com/#
|
Links
to Projects:
Home
Up
About
the Author:
An
astronautics engineer, the author is interested in studying artificial
intelligence and more specifically the intelligent agents created to
accomplish specific tasks. The goal of his projects are to build a
robotics test bed for experimentation and discussion amongst peers. Contact
Author |
