Latest guide
CNC Machining Tolerances: Where Precision Matters—and Where It Costs
A practical way to assign tolerances by function, protect critical interfaces, and avoid paying for precision the part does not need.
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Manufacturing knowledge, made practical.
Field-tested guidance for engineers and buyers making decisions about design, machining, materials, finishing, and production.
Guide selection
Choose the guide that matches the decision in front of you
| Option | Best for | Precision / evidence | Volume | Timing | Materials / scope |
|---|---|---|---|---|---|
| Tolerance guide | Fits, datums and controlled drawing requirements | Explains tolerance and inspection decisions | Any project stage | Use before RFQ | Cross-material guidance |
| Material guide | Grade and application screening | Property and machining trade-offs | Prototype to production | Use before material release | Metals and engineering plastics |
| Finish guide | Anodizing, plating and mechanical finishes | Dimensional build, masking and verification | Prototype to repeat batches | Use before drawing release | Aluminum, steels, brass and more |
| Case studies | Seeing process choices on real parts | Drawing and production evidence where published | Prototype and repeat production | Use before process selection | Project-specific |
6Published engineering guides
4Linked production case studies
Source-linkedTechnical references where used
How CNC Machining Quotes Are Built
Turning test pieces for a 6082 aluminum project took 15 to 40 minutes each as we refined the surface for later finishing. Here is how material, tolerances, finishing and quantity shape a CNC quote.
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Inside Our Micro & Swiss-Type Machining Process: From Bar Stock to Finished Parts
How small turned parts are made: tagged brass bar stock, Swiss-type machining on a Citizen Cincom R04VI, and optical inspection of micro connector contacts.
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Anodizing vs. Plating: Choosing a CNC Part Finish
Compare anodizing, plating and mechanical finishes for parts, including dimensional change and drawing notes. Read the guide before specifying a finish.
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Aluminum vs. Stainless Steel for CNC Machined Parts
Compare weight, strength, corrosion behavior, machining response, finishing options, and total project cost.
Compare the materials
From CNC Prototype to Low-Volume Production: What Should Change?
Turn a successful prototype into a repeatable small-batch process through revision control, first-article review, and inspection planning.
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