Dimensioning Formed Sheet Metal

5 edge distortion an exaggerated example of edge deformation is pictured in figure a below.

Dimensioning formed sheet metal.

Hit the hem just right and the numbers work. In a sheet metal design specifying hole sizes locations and their alignment is critical. Your manufacturer may not be able to match dimensions when creating the actual sheet metal part due to tooling and equipment limitations. There are other measurement units used to categorise metals by thickness though.

D 2 5t r see below the height can be less but it required secondary operations and is far more costly. It is always better to specify hole diameters that are greater than the sheet s thickness t. Since each metal fabricator has its own tooling bend factors and equipment to develop the flat blank it is better to fully dimension to formed views for that manufacturer. One needs to check that these factors are consistent with the tooling that will be used in manufacturing.

And also find you fold centers more easily. Millimetres mils gauge foils sheets and plates are pretty much the same with the only difference being in thickness. When producing drawings of sheet metal components i dimension from inside the flange walls. Some critical dimensions that need to be considered when setting up sheet metal in cad software are sheet metal thickness the k factor and bend radius.

Fortunately hems are rarely specified on tight tolerance flanges. Sheet metal is any metal that has a thickness in between 0 5 6 millimetres. Form height to thickness ratio to determine the minimum form height for sheet metal use the following formula. Their standard measuring process involved traditional equipment visual exams conducted by floor operators and templates that were often created in house.

Hit it softer or harder than necessary and the flange dimension changes. Trilux manufactures more than 9 000 sheet metal products including intricate luminaire bodies that form the basis of a commercial lighting unit. Hem measurement forming hems is one of those aspects of sheet metal that is very operator dependent.