Dimensioning Formed Sheet Metal

When producing drawings of sheet metal components i dimension from inside the flange walls.

Dimensioning formed sheet metal.

Their standard measuring process involved traditional equipment visual exams conducted by floor operators and templates that were often created in house. Sheet metal is one of the shapes and forms metal can be bought in. One needs to check that these factors are consistent with the tooling that will be used in manufacturing. Hem measurement forming hems is one of those aspects of sheet metal that is very operator dependent.

In a sheet metal design specifying hole sizes locations and their alignment is critical. 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. Sheet metal is any metal that has a thickness in between 0 5 6 millimetres. 5 edge distortion an exaggerated example of edge deformation is pictured in figure a below.

Form height to thickness ratio to determine the minimum form height for sheet metal use the following formula. And also find you fold centers more easily. Hit it softer or harder than necessary and the flange dimension changes. There are other measurement units used to categorise metals by thickness though.

I think this is the better way because you can acquire your cutting length without a flat pattern by adding the inside lengths fold allowance. D 2 5t r see below the height can be less but it required secondary operations and is far more costly. Hit the hem just right and the numbers work. My boss dimensions from outside the flange walls and thinks this is the.

Millimetres mils gauge foils sheets and plates are pretty much the same with the only difference being in thickness. 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. Fortunately hems are rarely specified on tight tolerance flanges.