What to Consider When Designing a Part for Roll Forming

To the uninitiated, the roll forming process might appear to be an easy business to work in and understand. However, there is a host of engineering guidelines and technical solutions that roll formers and experienced customers need to know. This small group of design considerations may not seem sophisticated, but it is. Just ask us.

The outside leg on the metal building panel stock, when rolled straight, will tend to be wavy…

Forming a slight bend in the leg will help to flatten it.

INSTEAD OF THIS… CONSIDER THIS…

The flat 180° hem, when roll formed, will be wavy…

By forming a tear drop hem, the edge will be flattened.

INSTEAD OF THIS… CONSIDER THIS…

90° legs on most metal building panels add more forming passes and will mark the legs…

Forming a 75° leg reduces the number of stations and does not mark the leg.

INSTEAD OF THIS… CONSIDER THIS…

Avoid sharp inside radii…

They are difficult to form without marking the outside radius or cracking the paint on pre-painted material. A larger radius reduces this problem.

INSTEAD OF THIS… CONSIDER THIS…

Roll breakage can occur because of a narrow slot design…

A wider slot design will alleviate the breakage.

INSTEAD OF THIS… CONSIDER THIS…

When the rolled leg is too short…

Using approximately 3 times the material thickness on the legs will help to achieve the desired stiffness.

INSTEAD OF THIS… CONSIDER THIS…

When a section has a roll form on one end and a wide flat on the other end…

Putting a leg on the end or a groove near the end to maintain straightness.

INSTEAD OF THIS… CONSIDER THIS…

If a wide sweeping radius is impossible to control…

Putting a bend in each end to keep it straight.

INSTEAD OF THIS… CONSIDER THIS…