文档介绍：Sheet Metal Design Services  
Sheet Metal Design Considerations
Tolerances
The punched feature-to-feature tolerance for Sheetmetal parts is +/-, with a general folding tolerance of +/-
Bend Relief
When a bend is made close to an edge the material may tear unless bend relief is given. Part 1 shows a torn part.
Part 2 shows a bend relief cut into the part, the depth of the relief should be greater than the radius of the bend.
The width of the relief should be a material thickness or greater.
Forming and Bending Near Holes
When a bend is made too close to a hole the hole may e deformed. “Hole 1” shows a hole that has e
teardrop shaped because of this problem. To save the cost of punching or drilling in a secondary operation the
following formulas can be used to calculate the minimum distance required:  
For a slot or hole < 25mm in diameter the minimum distance "D" = 2T + R (see below)
Send us an e‐mail: ******@   
 
Give us a Call: 0064 (3) 388 3187 or Fax 0064 (3) 3993183
Sheet Metal Design Services  
Corner Finishing
Type A
Standard Open Corner. A general-purpose corner for ponents where no finishing is required.
Type B
Closed Corner Flush One Side. For external finished corners where no welding is required but a clean tight corner is
needed.
Type C
Standar