Sheet Metal Design Guidelines
Views
- Create clear, uncluttered views that completely detail the part
- Use third angle orthographic projections
- Use a minimum of three views (front, top, side), isometric view with hidden lines removed will add clarity
- Provide detail views as required if it will avoid crowding, or if it will make an otherwise ambiguous view clear
- Include assembly details where necessary
- Draw part full scale and scale viewports instead.
Title Block
- Company Name
- Part name or number
- Part description
- Scale
- Designer's name
- Tolerances
- Material type, gauge, finish, masking details
- Units
- Revision block detailing all changes to part - use revision triangles to flag changes
Dimensioning
- Use ordinate dimensioning with a common datum between views
- Dimension all holes, including hole size for PEM fasteners
- Use hole charts for clarity if part contains many holes
- Provide a separate sheet for every part
- Fully specify PEM hardware and indicate side to insert from
- For grids of holes, indicate the pattern spacing - do not dimension all centers
- Do not dimension off of center line of part unless symmetry exists throughout
- For countersinks, specify the size of screw to countersink for
- Use appropriate tolerancing - if you don't need precise tolerances, don't use three decimal places
- Indicate welding location and type of weld
- Whenever possible, dimension flanges to the outside surfaces rather than to inside surfaces
- Do not dimension to non-measurable points
CAD formats
Our CAD modeling is done using SolidWorks, so solid models are preferable. However, we can read any of the following formats:
- SolidWorks (.SLDPRT, .SLDASM, .SLDDRW)
- Adobe Acrobat (.PDF)
- Pro-Engineer (.PRT)
- AutoCAD (R12, R13, R14).
- Other formats including .DXF, .IGS, .STEP, .SAT
Please supply us with CAD files via the Internet (compress attachments in a zip file when large) when requesting a quotation as they help to clarify hard to read drawings and drawings with missing dimensions.
Solidworks modeling requirements
- Use the thickness variable on base feature (or first shell) and link all subsequent cuts/extrusions to the thickness property.
- Consistently represent PEM hardware with correct hole size.
- Incorporate bend reliefs and notching cuts into parts.
- Use sharp bends and add 1/32" radii using sheet metal feature instead of filleting.
- Insert sheet metal features and confirm that the model will flatten.
- Avoid adding additional features after inserting sheet metal feature.
- Use a meaningful name in the design tree for each feature
- Use a separate sketch for each hole size
- fully define sketches and do not define in context of assemblies
- Take advantage of symmetry in your models by mirroring
- Make use of patterns and relations wherever possible
- Use inside corner to inside corner fitup for continuous external fillet welds, use closed corners (one flange overlapping the other) for internal stitch welds
Solidworks models that do not adhere to these standards are of little value to us and result in increased lead times and extra CAD fees.
No Software?
You can download free 2D CAD software here: http://www.3ds.com/products/draftsight/
