One number hides the model
A total without its assumptions cannot be reviewed or improved.
CNC estimating guide
How to quote CNC machining jobs with a reviewable cost model.
A step-by-step CNC quoting guide covering requirements, process fit, stock, setups, cycle time, tooling, outside work, inspection, risk, margin, and approval.
Build a defensible estimate
Every major assumption should survive review.
Lot and unit costs get mixed
Setup, material minimums, and outside charges behave differently from per-part cycle time.
Requirements arrive late
Inspection, certification, finish, packaging, or a revised quantity can overturn an otherwise sound machining estimate.
01 / 05
1. Confirm scope and revision
Identify the customer, part number, revision, quantities, required date, material, finish, drawing, CAD, specifications, inspection level, packaging, and shipping terms.
Record ambiguities before costing. A quote built on an assumed revision or missing specification is not faster; it merely moves the delay into rework or production.
- Part and revision
- Quantity breaks
- Material and finish
- Quality and delivery requirements
02 / 05
2. Choose process, stock, and machine
Review geometry for milling, turning, or mixed-process fit. Select a stock form and size with machining allowance, supplier provenance, purchase minimum, and expected material utilization.
Check the part and workholding concept against a real machine profile. Axis access, envelope, bar capacity, live tooling, and secondary operations can change both setup and cycle assumptions.
- Process fit
- Stock form and size
- Machine capability
- Workholding and access
03 / 05
3. Build setup and cycle from drivers
Estimate programming and setup as lot-level work. Estimate cutting, tool changes, probing, handling, deburring, and repeated inspection as per-part work where appropriate.
Use recognized features and similar jobs as evidence. Preserve the estimator's adjustment and reason. That creates a model that can later be compared with CAM or production instead of an isolated guess.
- Programming and setup
- Cycle minutes per part
- Tooling and workholding
- Estimator adjustment
04 / 05
4. Add everything outside the machine cycle
Include material freight and minimums, purchased hardware, heat treatment, plating or coating, outside machining, special tooling, FAI or CMM work, certificates, packaging, and supplier lead time.
Reconcile assembly quantities through the BOM. A purchased component with a 100-piece MOQ should charge the required purchase quantity even when the customer orders twenty assemblies.
- Outside services
- Purchased components
- Inspection and certification
- Critical lead path
05 / 05
5. Apply risk, margin, and commercial review
Use explicit risk or contingency only where uncertainty remains; do not bury a known missing supplier cost inside margin. Apply overhead and margin according to shop policy, then test quantity breaks and lead-time options.
Before release, confirm the current source files, material source, supplier responses, BOM, DFM findings, customer-facing scope, validity, payment terms, and delivery terms. Save the approved revision and later record win, loss, and actual job evidence.
- Risk and contingency
- Overhead and margin
- Approval checklist
- Outcome and calibration
Straight answers
Where a reviewable CNC cost model needs judgment.
What is the most common CNC quoting mistake?
Treating a cycle-time guess as the whole cost while missing setup, material constraints, outside work, inspection, and requirements.
Should setup cost be divided by quantity?
It may be presented per unit, but it should remain a visible lot-level assumption so quantity-break behavior stays correct.
How do shops improve quote accuracy?
Compare estimate drivers with CAM and production evidence, record estimator changes, and recalibrate by process and machine.
Build a defensible quote
Price one job line by line instead of hiding the total.
Use known material, setup, cycle, outside work, inspection, risk, and margin evidence to test the model.