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- Design the part to be machined in the fewest number of clampings possible
- Radii should usually be greater than 1/8". A 1/8" end mill is a common small end mill size
- Features requiring an end mill longer than 4 times it's its diameter are usually difficult to machine
- Fillet internal corners
- A boring bar can be used on the student shop manual mills to bore large diameter holes
- External radii are usually difficult to machine accurately on a manual mill but you can alway use a file to add cosmetic fillets
- Steel is more difficult to machine than aluminum
- Tight tolerances will likely increase cost and manufacturing time
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