Things to avoid:
- Exceeding maximum thickness for common materials
- Over-designing corners & edge conrequires
- Embossing / Partial Shear
- Bend Radii minimums & preference
- Tolerance preferred & Achievable
Flat Pattern Interference
- Post operations (Milling & Drilling) add $$
- Plating of flat parts
- Features close to bends 2-3x material thickness min.
- Parts that don’t nest well (Wasted material)
Corner Style Tips
- Corner style is a factor of cost and process, radii are the most economical for
- most processes, standard fractional values apply well.
- Edge conditions are derived from process.
- Stamped parts have die break
- Laser cut parts have heat affected zone.
- Laser can use specific assist gas to produce unique edge quality.
- Adds strength and/or clearance.
- Can add stress or warping to material.
- Good for locating features.
- Material is displaced from surface to surface.
- Feature definition and clearance.
- Material is displaced from one surface.
- Modern tooling techniques allow for minimum bend radii with production tooling. Most parts can be formed with .010” bend radii. (adds Stress).
- Prototyping and short run production requires the use for standardized tooling typical inside radii of .01”, .03” or .06” reduce cost.
Bend Relief Minimums & Preference
- Bend reliefs are a function of allowing detachment of material to allow the material to bend freely.
- Punching & Stamping of material requires bend relief of 1-1.5x material thickness.
- Laser beam widths vary from .010”-.025”.
- Waterjet cut width is .030” minimum.
Tolerance Preferred and Achievable
- #1 cost adder to most parts.
- Industry standards allow +/-.005-.007” across each bend.
- Most default print tolerances are +/-.005”. By setting standard .xxx tolerance to .010”, savings will be realized.
- Flat part 1-50 pcs, 2 days, 50-1000 3-4 days
- Formed prototype part 1-50 pcs, 5-7 days
- Drawn part 1-50 pcs, 10-15 days
- 4 Slide Tooled part, 4-6 weeks
- Expedite options are available $$$$