General Cost Reduction Tips
- Use popular materials and check the pricing on different types.
- Harder materials (e.g. steel and stainless steel) are usually more expensive than softer materials (e.g. aluminum, plastic, etc.).
- Make parts multi-functional to reduce part types.
- Increase quantity to reduce cost per part.
- Use the loosest applicable tolerance.
- Use common and simple finishes. Avoid multiple finishes. Use a material that does not require an extra finish process.
- Convert single complex parts into multiple simpler parts that are “fit” together. For example, to create a large block with a thin rod or boss feature protruding from the center you can design the block and rod feature separately. Piecing them together may require fastners or possibly welding. To do it in one piece requires starting with a large block of material and can use ten times as much material compared to making the rod and block separately.
- Tap holes no deeper than three times the diameter when the hole and bolt are the same material (deeper usually adds no strength and can substantially increase the chance of tap breakage, time and cost).
Geometry Design Cost Reduction Tips
- Make shapes simpler or smaller.
- Avoid fine details in shapes.
- Avoid sharp inside and outside corners.
- Increase the radius of inside and outside corners.
- Design shapes that don’t waste material. For example, a large U shaped part might be more efficient in three separate sections to avoid wasting the material in the center.
- For 3D parts minimize the number of different hole diameters.
- Avoid shapes with long protrusions, thin shapes, shapes with lots of material removed, etc.
- Avoid the need for complex work-holding. Rectangular parts are the most practical. Round parts requiring milling are a little more difficult.
Shapes with complex outer shapes are the most time consuming to setup for holding.
- Make narrow slots and channels wider – narrow areas require small cutting tools which work slowly.
- Avoid adding explicit chamfers or rounding to edges in a CAD design as edges are normally broken by more economical methods.
- Inside deep pockets, for any protrusions close to walls (e.g mounting posts) join the protrusion to the wall so it’s not a separate “island”.
Cost Reduction Tips for Sheet Metal Bends
- Sometimes complex bends are more economical and easier to fabricate if you design two simpler parts that bolt together.
- Design bent parts to pack efficiently. For example, in designing a large box consider making the sides of the box separate with bolted flanges. Packing efficiency is more important with larger parts. Parts with one bend generally pack much better than parts with two bends. Bends with angles greater than 90 may pack better than those with 90-degree bends.