When working with sheet metal parts, use either Creo Elements/Direct Modeling or Creo Elements/Direct Sheet Metal, and not both! Creo Elements/Direct Sheet Metal derives the K-Factor from the tool database, whereas Creo Elements/Direct Modeling Help uses a user-defined K-Factor. Switching between the Creo Elements/Direct Modeling and Creo Elements/Direct Sheet Metal can lead to incorrect unfolding of sheets.
Designing sheet metal parts with Creo Elements/Direct Sheet Metal
Sheet Metal's design and advisor capabilities allow you to easily create sheet metal parts. They reduce the number of steps and the time required to model a part compared to modeling a part using only Creo Elements/Direct Modeling commands.
Creo Elements/Direct Sheet Metal makes many tasks easier:
• Create either a flat sheet or a multiple bended sheet part using a single command.
• Automatically generate bend radii, bend reliefs, and corner reliefs.
• Automatically attach material information to the part when you select the desired material.
• Easily add lips, hems, and offsets to a part using a single command.
• Quickly and easily add punch or stamp features to a part without having to model them, because many punch and stamp tools are provided by the technology database.
• Easily change bend radii.
• Easily move, rotate, or delete holes and stamps.
Designing for Manufacturability
Design for Manufacturability (DFM) is supported by several Creo Elements/Direct Sheet Metal design processes, functionality and the constant DFM feedback.
• Creo Elements/Direct Sheet Metal provides a selection of preferred materials, punch shapes and sizes, and feature parameters for bend reliefs, hems, and so forth. Pop-up tables in Creo Elements/Direct Sheet Metal show you which materials, punch shapes and sizes, and feature parameters are available at a specified fabrication shop, and which are preferred at that particular shop. This makes you aware of the parameters that result in the most conveniently manufactured parts.
• As you place tools on the part, DFM provides visual checks. Creo Elements/Direct Sheet Metal helps you check for the possibility of undesirable deformation by providing 2D punch profiles. Each punch profile includes the hole outline, a minimum hole distance zone outline, and a deformation zone outline. You can use these outlines to check whether a minimum hole distance zone or deformation zone overlaps another hole or stamp, indicating that undesirable deformation may occur. You can relocate holes that would potentially cause undesirable deformation or leave all holes in their present locations even though deformation may occur.
During the punching and stamping operations, Creo Elements/Direct Sheet Metal automatically checks for minimum distance violations. It checks from a hole or stamp to the outer contour of the sheet, to another hole or stamp, or to a bend.
If violations occur, Creo Elements/Direct Sheet Metal displays a window containing a description of the violations. This leaves you with several options:
• Continue the operation.
• Interrupt the operation and relocate the tool.
• Cancel the operation and try something different.
The Technology Database (TDB)
The Technology Database (TDB) is a collection of fabrication shop manufacturing data. It is based on ASCII files and Creo Elements/Direct Modeling workplanes, profiles, and parts.
The TDB stores process information for the sheet metal fabrication. This includes:
• Materials
• Punching and stamping tool shapes and sizes
• Process characteristics (for example, bending allowance)
The TDB helps you to accelerate the design process as well as increase CAD performance:
• It provides 2D profiles and 3D parts of punch and stamp tools.
• It simplifies and automates the creation of hems, offsets, bend reliefs, and bend radii.
• It attaches material type and thickness attributes to a part.
The TDB encourages the use of preferred materials and tools by informing you of the preferred values for these entities. Using only preferred materials and tools has several advantages:
• It can reduce the turnaround time for obtaining parts and the part cost.
• It makes the part easier to manufacture because the preferred size tool is available and may already be set up in the punch turret. This may also reduce the part cost.
• Designs using materials and tools preferred at multiple fabrication shops can be easily manufactured at all of those shops, so you can select the shop with the shortest queue or fastest turnaround time.
Creo Elements/Direct Sheet Metal enables you to quickly generate and install new punch and stamp tools. The following main steps are necessary to build a new tool:
• Define the contour of the new tool as 2D geometry in a workplane.
• Save the workplane in a file.
• Add an entry to the Technology Database file to append the new tool to the Creo Elements/Direct Sheet Metal punch tool table.
Creo Elements/Direct Sheet Metal automatically searches for any customer-specific tools when it is started. You can also use the files directly like regular tools.
Generating flats
Creo Elements/Direct Sheet Metal can generate an accurate 2D drawing of a flattened (unfolded) sheet metal part. With a single command, Creo Elements/Direct Sheet Metal generates the flat directly from the 3D model.
This flat can be viewed in a Creo Elements/Direct Modeling workplane or automatically loaded in Creo Elements/Direct Drafting. Shops that use CNC software can load the file of the flat directly into the CNC punching programs used to punch the part.
Alternatively, flats can also be generated directly in Creo Elements/Direct Annotation. The smooth integration of the Creo Elements/Direct Sheet Metal and Creo Elements/Direct Annotation modules means that documenting associative 2D drawings can be done quickly and efficiently.
This saves time by generating the flat in Creo Elements/Direct Sheet Metal or Creo Elements/Direct Annotation instead of generating the flat drawing manually. Flat drawings can also be used to show details on design models. The flat can be plotted and used on foam core or cardboard design models.
The generated flat is also useful as a visual DFM check because it identifies potential manufacturing problems. These problems are highlighted with a user-definable color in Creo Elements/Direct Drafting and Creo Elements/Direct Annotation.
If parts designed by means of Creo Elements/Direct Sheet Metal are produced in two or more shops, note that the same tool geometry may produce different bend radii -- especially if the same part design is used in multiple countries where different conditions apply (such as different material grades, different oils, and so on).
To support multiple-shop production, Creo Elements/Direct Sheet Metal derives the bend radius annotation in the flat from the tool radius data rather than from the part geometry. Refer to the Creo Elements/Direct Sheet Metal Administration Guide for further information.
Relationship of Creo Elements/Direct Sheet Metal, Creo Elements/Direct Modeling, Creo Elements/Direct Annotation, and Creo Elements/Direct Drafting
Sheet metal designs created using Creo Elements/Direct Sheet Metal are stored as parts, but have additional attributes such as material type stored with them. You can manipulate these parts and files in any way that Creo Elements/Direct Modeling parts or files can be manipulated, including file translations, file transfer, Creo Elements/Direct Modeling modifications to the part, and so forth.
You can execute Creo Elements/Direct Modeling commands on parts created using Creo Elements/Direct Sheet Metal and vice versa. You can also use Creo Elements/Direct Sheet Metal commands to generate a flat of a part designed using Creo Elements/Direct Sheet Metal, Creo Elements/Direct Modeling, or a combination of the two. Flats and other associative views can also be created directly in Creo Elements/Direct Annotation to create 2D drawings, which can then be annotated with dimensions, text, symbols, and so on.
There are, however, some limitations to using Creo Elements/Direct Sheet Metal commands on Creo Elements/Direct Modeling Help parts.
Encoding
The Creo Elements/Direct Sheet Metal shop and cost model files shipped with Creo Elements/Direct Modeling are encoded in UTF-8.
To make sure that Creo Elements/Direct Modeling recognizes the encodings of Creo Elements/Direct Sheet Metal files correctly, they must start with a BOM if they are encoded in UTF-8 or UTF-16. Creo Elements/Direct Modeling assumes Roman8 or SJIS (depending on which language version of Creo Elements/Direct Modeling you are running) encoding for Shop files not starting with a BOM.
Hence, legacy shop files do not necessarily have to be converted. However, we recommend you use the IKIT API (oli:sd-recode-textfile) to convert legacy shop files to UTF-8 before modifying them. This makes editing much easier and also fixes any extended character problems for those legacy files.
