1. Design considerations for parts mass-produced on the mill:
a. Number of operations
i. Additional operations will increase cycle time by more than 25 seconds (time it takes to place a new part into the mill)
ii. Additional operations will also increase setup time
1. Fixture the part appropriately
2. Program a new CAM sequence
b. Number of parts
i. It may save time by making fewer but more complex parts than by making more but simpler parts for a device due to decreased setup and turnover time
c. Accuracy/Tolerance
i. Thinner materials are more likely to deflect
ii. Softer materials are more likely to deflect
iii. Stock size will vary
iv. Accuracy is inversely proportional to cycle time
v. Smaller end mills will deflect more, especially with deeper cuts (>1”)
d. Rounded Corners
i. The inside corners will have a radius that is half the diameter of the end mill
e. Fixtures needed
i. Parts that are thin (<0.25”), have non-rectangular geometries, or irregular angles may need a fixture because of the inability to hold the part in the vise
1. Increases setup time (Time needed to design and fabricate a fixture that would yield accurate and consistent results)
2. Manufacturing Considerations
a. Resource allocation
i. Parts turnaround time could be reduced with addition of more people
1. Setup time could be as long as the production time depending on part complexity and number of parts made
ii. Always purchase more stock than required
1. It is almost guaranteed that parts will be scrapped during the manufacturing
iii. Also make more than what is required
1. Setup of subsequent operations may cause some materials to become scrap
b. Programming efficient operations
i. Bigger end mill = shorter cycle time
ii. Use a large end mill to rough the part and a small end mill for finishing (if needed)
c. Provide samples before mass production
i. An error in the CAD file or wrong tooling may cause parts to not conform to specifications
d. Do one operation at a time when mass producing
i. Reduces setup time
