Design Criteria to Consider
(other grades available upon request)

Working from the designer's drawing, Amerex will make the shape as near as possible to the design drawing. However, a full knowledge of the shape's end use may enable Amerex to make preliminary design suggestions.
Standard extruded tolerances should be used in eliminating extra cost or delay in production.
Camber or Bow Tolerances

Camber or bow tolerance is based on the greatest deviation of a side from a straight line. Acceptable camber or bow tolerance is .025 inches in any foot.

Twist Tolerances

The amount of spiraling in an extruded shape is called twist. It can be measured by the height of the high corner from a flat reference base. The twist tolerance must not exceed established rise x number of feet in length.

Section Width
1/2 inch to 1-1/2 inches
Over 1-1/2 inch to 4 inches
Over 4 inches

Rise Per Foot
.025 inch
.038 inch
.050 inch

Angular Tolerances

Tolerances on angles will not exceed plus or minus 2 degrees

Transverse Flatness Tolerances

The transverse flatness tolerance is the maximum deviation from a reference base across any cross section flat surface. Allowable deviation from flat is.010" per inch of width. Minimum deviation dimensions of less than 1 inch is .010"


In some instances, customers ask for a material grade which is either unavailable or has a long purchase lead time. There may be alternate materials available which meet the customer's design criteria, which we would be prepared to investigate upon request.