Hemmed Seam Sheet Metal

Hemming is the process in which the edge is rolled flush to itself while a seam joins the edges of two materials.
Hemmed seam sheet metal. The edges of metal. With hemming the edge of sheet metal is folded so that it becomes flush with the area onto which it s rolled. With seaming the edge of sheet metal is folded but it doesn t sit flush. Hemming and seaming are two similar metalworking processes in which a sheet metal edge is rolled over onto itself.
This is putting a simple hem on a curved piece of zinc with a 7ft radius. Hemming is a metalworking process where a sheet metal edge is mechanically bent to fit an uneven surface or simply roll over onto itself. Hems are commonly used to reinforce an edge hide burrs and rough edges and improve appearance. Rather the two layers of the folded sheet metal are joined using a seam.
Seaming on the other hand is a metalworking process that uses a similar process of rolling sheet metal over and onto itself except it uses a seam to join the two layers. And while hems or seams reinforce a sheet metal edge their main purpose is to improve appearance by hiding burrs and rough edges on metal back splashes and other sheet metal installations. Create a bend with acute angle tooling in the metal 30 is preferable but 45 will work for some circumstances. Roller hemming is a mechanical joining technology well suitable to produce form locking linkages of large sheet structures.
Am i missing something here or are manual work arounds required when. Basically they dont work. Seams are commonly used in the food industry on canned goods on amusement park cars in metal roofing and in the automotive industry. The video shows exemplarily how.
There appears to be a limitation when it comes to using the miter flange and closed corner tools with hems and seams. You ll often find seams on metal roofs.