Sheet Metal Part Tolerance

Fabrication tolerances for dimensional variance in sheet metal and machined parts.

Sheet metal part tolerance.

In the above example m and k has defined the tolerance class. Tolerance class is defined as per design requirements and manufacturing capability. They re averages and spec variation from one sheet or batch to the next creates inconsistencies especially when it comes to material thickness. Recommended minimum distance between two hole centers in sheet metal design should be equal to sum of hole radius plus two times the sheet thickness.

The resulting bend angle variation and sometimes the required adjustment to the flat layout contributes to the reason that machined parts typical tolerance of 0 002 in can routinely have tighter tolerances than precision sheet metal parts typical tolerance of 0 010 in. Recommended distance radius of hole1 radius of hole2 sheet thickness. In those cases please contact us so we can discuss your options. You may see a dimension s tolerance written with the symbol.

Geometrical tolerances for features without individual tolerance indications. All bend tolerances for the entire part added together. The tolerances shown are well suited to the progressive stamping process and thus ensure quality and cost effective parts. For sheet metal parts iso 2768 mk is used.

Can be anywhere from 0 129 to 0 141 in. While both can achieve highly accurate bends each type of equipment offers its own advantages. For sheet metal parts iso 27 68 mk is used. But these aren t exact specifications.

A36 material has a gauge zone tolerance of 0 006 in. As per design requirements and manufacturing capability tolerance class is defined. As shown in the figure below it is a simplified diagram of a complex bending sheet metal part. We use an x y and angular micro adjust which allows for a respectable tolerance of 0 020 0 51mm this is more than adequate for most applications.

1989 general tolerances part 2. Recommended center distance between holes in sheet metal part. A definition the american society of mechanical engineers defines tolerance as the total amount that a design s dimension can vary. Progressive tooling is ideal for complex parts that require several steps to be completed from the flat strip to the finished part.

Due to the existence of the sheet metal bending tolerance in the direction of the bending of the sheet metal a certain bending gap needs to be secured to avoid the bending failure caused by the interference during the bending. General tolerance iso 2768 does not specify where to use these tolerances. And for machined components iso 2768 fh can be used. A part design can present tolerance as an upper limit and a lower limit or an allowable range.

And for machined components iso 27 68 fh can be used. For instance typical 10 ga.