RMA Standard Cross-Sectional Tolerance

RMA Standard Cross-sectional Tolerance Tables

For outside diameters, inside diameters, wall, width, Height, and general cross-sectional dimensions of extrusions.

Metric Tolerances

RMA Class

Drawing Designation
Dimensions in Millimeters

0.0 to 1.5
1.5 to 2.5
2.5 to 4.0
4.0 to 6.3
6.3 to 10.0
10.0 to 16.0
16.0 to 25.0
25.0 to 40.0
40.0 to 63.0
63.0 to 100.0

High Precision
“E1”
Tolerance
+/-0.15
+/-0.20
+/-0.25
+/-0.35
+/-0.40
+/-0.50
+/-0.70
+/-0.80
+/-1.00
+/-1.30

Precision
“E2”
Tolerance
+/-0.25
+/-0.35
+/-0.40
+/-0.50
+/-0.70
+/-0.80
+/-1.00
+/-1.30
+/-1.60
+/-2.00

Commercial
“E3”
Tolerance
+/-0.40
+/-0.50
+/-0.70
+/-0.80
+/-1.00
+/-1.30
+/-1.60
+/-2.00
+/-2.50
+/-3.20

English Tolerances

RMA Class

Drawing Designation
Dimensions in Inches

0.0 to 0.06
0.06 to 0.10
0.10 to 0.16
0.16 to 0.25
0.25 TO 0.39
0.39 to 0.63
0.63 TO 0.98
0.98 to 1.57
1.57 TO 2.48
2.48 to 3.94

High Precision
“E1”
Tolerance
+/-0.006
+/-0.008
+/-0.010
+/-0.014
+/-0.016
+/-0.020
+/-0.027
+/-0.031
+/-0.39
+/-0.051

Precision
“E2”
Tolerance
+/-0.010
+/-0.014
+/-0.016
+/-0.020
+/-0.027
+/-0.031
+/-0.039
+/-0.051
+/-0.063
+/-0.079

Commercial
“E3”
Tolerance
+/-0.015
+/-0.020
+/-0.027
+/-0.031
+/-0.039
+/-0.051
+/-0.063
+/-0.079
+/-0.098
+/-0.126