How To Note Flatness Sheet Metal Drawings

Bend tags associate rows in a bend table with the view geometry.

How to note flatness sheet metal drawings. I am apply my dimensions carefully so that they are unambiguous. Perfect flatness is when all points of a surface lie in the same plane. Although notes on each drawing will differ the first note on all sheet metal drawings that contain bends should be as follows. Minimum bend reliefs allowed.

The boxed symbols can be read this surface must lie between two parallel planes spaced 0 2 apart in all views the right figure shows a possible actual part condition. Toggling the visibility of bend lines. I systematrically specify bend radii on my drawings and i include details showing what the bend corners look like before bending. I want stress relief radii.

Toggling the visibility of sheet metal bend notes. For door panels front panels interior panels and racks see document 10 1006 for information on adding a note regarding the implementation eps 121. Sheet metal bend line notes. To control the bow try using straightness applied to your sheet metal gauge thickness feature of size.

After you insert the bend table in the drawing bend tags are added to the selected drawing view automatically. Note that the flatness tolerance must be less than the size tolerance associated with the surface. Bend tags are formatted by the dimension style and do not have a leader by default. It is a common symbol that references how flat a surface is regardless of any other datums or features.

The flatness control c defines how much a surface on a real part may vary from the ideal flat plane. Flatness is a form control. It comes in useful if a feature is to be defined on a drawing that needs to be uniformly flat without tightening any other dimensions on the drawing. Dimensions given on a flat pattern are affected by several bending factors like k factor and bend radius during the 3d modeling stage.

I don t put any standard notes on my sheet metal drawings. Unless you need the part to have a flatness that is better than the sheet metal gauge tolerance. The flatness control c defines how much a part s surface may deviate from its perfect flat form. I have read up on and taken a course on the asme y14 5m 1994.

Creating drawings of flat patterns. No mmc or lmc applicable. Toggling the visibility of bend region lines. To put a flatness on sheet metal part will be hard to control because of the stock sheet metal gauge size tolerances are relatively nice and tight.

The flat pattern drawing doesn t always list these factors. Gd t flatness is very straight forward. Yes new in 2009 drawing callout. Flat pattern drawing views can display bend line notes or bend tables.