How Much to Machine on CNC 5 Axis

• 1
  Key takeaways
• 2
  What Sets the Base Cost to Machine on CNC 5 Axis
• 3
  Material Choice and How Much It Adds
• 4
  Tolerance, Surface Finish and Inspection Load
• 5
  Batch Size, Setup Amortization and Lead Time
• 6
  How to Get an Accurate Five-Axis Quote
• 7
  How Cost Drivers Compare Across Common Jobs

Every five-axis quote starts with the same three numbers: programming hours, setup hours, and cutting hours. Programming for a simultaneous five-axis toolpath usually runs 2 to 6 hours on a moderately complex part, because the CAM engineer has to verify tool holder clearance and rotary travel before the first cut. Setup on a Ø400 mm rotary table takes 1 to 3 hours depending on how the blank is held.

Cutting hours are the only line that scales with batch size. On a 6061 aluminum bracket measuring 180 × 120 × 60 mm, roughing and finishing typically run 25 to 50 minutes per part. Switch that same part to 17-4PH stainless and the cycle time roughly triples, because surface speed drops and the tool needs more passes at the same depth of cut.

The mistake we see most often is a buyer comparing a five-axis quote against a three-axis quote and assuming the hourly rate is the difference. It is not. The five-axis machine does the part in one setup, so you pay for one fixture instead of three, and you remove the re-datum error that comes with each re-clamp. On a part with features on four faces, that difference usually pays for itself above 20 pieces.

If you want a fast sanity check, ask the shop to break the quote into programming, setup, cycle time, material, and finishing. A shop that cannot split those lines is guessing. A shop that can gives you something to negotiate against, and you can see immediately whether the cost sits in the geometry or in the quantity.

Material price per kilogram is the obvious part. The less obvious part is machinability, which drives cycle time and tool wear. Aluminum 6061 and 6082 cut fast and hold good finishes, which is why prototype work gravitates to them. 7075 is stronger but gummier at high removal rates, so feeds and speeds need tuning.

Stainless 303 and 304 machine at roughly 40 to 50% of the aluminum removal rate. 316L is worse. Titanium TC4 (Ti-6Al-4V) and Inconel sit lower still, and they punish any toolpath that dwells in the cut. On these alloys, a five-axis machine earns its keep because it can keep the cutter engaged at a constant chip load instead of lifting in and out.

There is a second cost that rarely appears on a quote: heat and distortion. Thin titanium walls move after roughing, so the process needs a stress-relief pass or a semi-finish leave of 0.3 to 0.5 mm before the finishing cut. That is real machine time. If your part has walls under 1.5 mm in titanium, expect the quote to reflect it.

Plastics are a different story. POM and PEEK cut easily but need sharp tooling and good chip evacuation to avoid melting. Carbon fibre is abrasive and eats carbide, so tool life, not cycle time, becomes the cost driver. Tell the shop the exact grade, not just the family.

A general machining tolerance of ±0.05 mm is comfortable on most five-axis work. Tightening the critical features to ±0.005 mm changes the process, not just the drawing. The shop has to control thermal drift, use a warm-up cycle, and often finish with a spring pass. On a 200 mm part, that alone can add 15 to 30 minutes of machine time.

Surface finish follows a similar curve. As-machined surfaces at Ra 1.6–3.2 μm come straight off the cutter. Ra 0.8–1.6 μm usually needs a finer stepover or a dedicated finishing tool. Ra 0.2–0.8 μm on a five-axis contoured face means slower feed, a smaller stepover, and sometimes a lap or polish step that cannot be automated.

Inspection is the line buyers forget. A part with three tight features can be verified with a micrometer and a few gauge pins. A part with fifteen tight features across five faces needs CMM time, and CMM time is charged by the hour. On small batches, inspection can reach 10 to 20% of the total.

The practical rule: apply tight tolerance only to the features that actually mate or locate. Every extra ±0.005 mm callout on a non-functional surface adds cost and adds no value. Engineers who mark up drawings this way usually get a quicker quote and a lower one.

Setup cost does not disappear with volume, it spreads. If programming and setup total 6 hours on a job, one part carries all 6 hours. Fifty parts carry 7.2 minutes each. That is why the per-part price drops steeply between 1 and 50 pieces, then flattens.

Above roughly 200 pieces, the curve flattens further and material becomes the largest controllable line. At that point, buying bar stock in the right diameter instead of hogging from plate can cut both material cost and cycle time. On a 10,000-piece run, a 10% cycle-time reduction is worth more than any negotiation on the hourly rate.

Lead time is a separate lever. Standard turnaround on five-axis parts is 3 to 5 days after production starts, and production can begin within 24 hours of a released order. If a job needs a custom fixture, add 2 to 3 days for design and build. If it needs an outside finish such as hardcoat anodizing, add the plating queue.

We do not set a minimum order quantity. A single prototype and a 10,000-piece run go through the same quoting path, though the economics are obviously different. For prototypes, ask for the three-axis option too. Sometimes it is cheaper, and sometimes it is not. You want the comparison.