| SOLID
SHAPES |
|
| 1. |
(a) As-Extruded |
| Size |
Tolerances
Plus and
Minus |
| Over |
Up
to and Inc. |
| mm |
Imp |
mm |
Imp |
mm |
Imp |
| - |
- |
20.0 |
0.75" |
0.26 |
0.010" |
| 20.0 |
0.75" |
39.0 |
1.5" |
0.38 |
0.015" |
| 39.0 |
1.5" |
51.0 |
2.0" |
0.50 |
0.020" |
| 51.0 |
2.0" |
89.0 |
3.5" |
0.64 |
0.025" |
| 89.0 |
3.5" |
108.0 |
4.25" |
0.76 |
0.030" |
| 108.0 |
4.25" |
- |
- |
0.88 |
0.35" |
|
|
(b) Drawn
Half above As-Extruded tolerances. |
|
|
| 2. |
Straightness
(a) Drawn - 1/4" maximum in 12ft (6.35mm in 3.6m).(b) Extruded-Only
- 1/2" maximum in 12ft (12.7mm in 3.6m). |
|
|
| 3. |
Twist Tolerances
(a) Metric |
| Width
/ Length |
per
0.4 metre |
per
1 metre |
2
metres or greater |
| 0
- 18mm |
0
- 0.9mm |
0
- 1.8mm |
0
- 3.6mm |
| 18
- 30mm |
0.9
- 1.2mm |
1.8
- 2.4mm |
3.6
- 4.5mm |
| 30
- 50mm |
1.2
- 20.0mm |
2.4
- 4.0mm |
4.5
- 7.5mm |
| 50
- 80mm |
2.0
- 2.4mm |
4.0mm |
7.5
- 8.0mm |
| 80
- 120mm |
2.4mm |
4.0
- 4.8mm |
8.0
- 9.6mm |
| 120
- 200mm |
2.4
- 3.0mm |
4.8
- 6.0mm |
9.6
- 12.00mm |
|
|
(b) Imperial |
|
|
| Width
/ Length |
per
16" |
per
39" |
78"
or greater |
| 0"
- 0.7" |
0"
- 0.035" |
0"
- 0.070" |
0"
- 0.142" |
| 0.7"
- 1.2" |
0.035"
- 0.047" |
0.070"
- 0.094" |
0.142"
- 0.177" |
| 1.2"
- 2.0" |
0.047"
- 0.078" |
0.094"
- 0.157" |
0.177"
- 0.295" |
| 2.0"
- 3.1" |
0.078"
- 0.094" |
0.157" |
0.295"
- 0.315" |
| 3.1"
- 4.7" |
0.094" |
0.157"
- 0.189" |
0.315"
- 0.378" |
| 4.7"
- 7.9" |
0.094"
- 0.118" |
0.189"
- 0.236" |
0.378"
- 0.472" |
|
| 4. |
Angularity
Allowable deviation from specified angle +/- 1° |
|
|
| 5. |
Curved Surfaces
Allowable deviation per inch of chord length -0.004"
(0.10mm per 25mm). |
|
|
| 6. |
Flat Surfaces
Allowable deviation from flat -0.007" per inch width
(0.18mm per 25mm) |
|
|
| 7. |
Cut Ends
Maximum allowable deviation from square -1.5° |
|
|
| 8. |
Corner Radii
Unless otherwise specified +/- 1/32" (0.8mm). |
|
|
| 9. |
Length + 0.5"
- Nil (+12.7mm - Nil). |
|
|
| HOLLOW
SHAPES |
|
|
| 1. |
Generally,
hollow shapes require a broader range of tolerances that those quoted
above for solid shapes. |
|
|
| 2. |
The actual
tolerance applied will depend partially on the complexity of the
shape involved. |
|
|
NOTE:
Tighter tolerances may be achieved by prior agreement at the design
stage. |