True Material Thickness

In our quest to provide the closest tolerance products possible, we found an inherent industry wide problem that everyone else overlooked  Just like wood two by four studs that at some time must have actually measured 2 x 4 inches but no longer does, sheet steel does not come delivered at  "book thickness"; unless you buy an entire mill run or buy stamping quality at a great premium. The thickness the mills roll out are on the thinnest edge of the industry accepted mill tolerance, which is up to .006" +/- of the thickness (e.g. 7ga book thickness = .179" but the mill runs at .173"). I encourage my customers to use true material Thickness in their new drawings to ensure the most accurate parts possible.

We realized this discrepancy while trouble shooting parts that were not within customer specifications.  Knowing that our equipment and procedures could meet the criteria, we found that error was in the called out material thickness on the drawing.  The designer started out using "book thickness"  that built in up to a .006" error with every bend on the part. When we design a part, we will use the actual thickness and bend radius for as perfect a part as possible.  I don't know of any other fabricator that has dug down to this level of perfection.