# Calculate what a turned part should cost.
URL: https://arcnm.io/manufacturing/cnc-turning
Language: en

A turned part is costed from its stock, its cuts and its secondary features. ARCNM recognises a rotational part in the STEP geometry. It sizes the bar or blank and times the roughing and finishing cuts. It prices threads, grooves, bores and cross-holes. Then it picks the machine class that wins at your lot size. The options are a 2-axis lathe, a live-tool turning centre, a Swiss-type lathe or a mill-turn machine. The result is a unit cost per quantity with the routing behind it.

## At a glance
- Inputs: STEP model of a rotational part; PDF drawing optional (fits, finish)
- Machine classes: 2-axis lathe · live-tool turning centre · Swiss-type · mill-turn · band / circular saw for cut-to-length
- Standards applied: ISO 286 fits · ISO 2768 · ISO 513 · DIN 8580
- DfM checks: narrow groove, deep groove, length-to-diameter ratio, deep hole needs peck drilling, bore breakout
- You get: bar or blank size, routing with setups and time per operation, threads and secondary features priced, machine class chosen per lot size

## What do you get for a turned part?
ARCNM sizes the stock and times the roughing and finishing cuts. Threads, grooves, bores, drilled and reamed holes are priced as their own operations. Each has its setup and cycle time on the lathe chosen for the lot. Cross-holes and flats go to a live-tool station when your fleet has one. So a second machine appears on the routing only when it is really needed. Material is priced from the bar actually consumed. Every line on the cost sheet names the feature behind it.

## What moves the price of turned parts?
Stock utilisation comes first. A stepped shaft turned from a bar wastes everything between the bar and the finished profile. Then the length-to-diameter ratio and tight fits such as H7/g6, read from the drawing. Surface finish, thread count and any milled features that force a second setup also count. ARCNM prices each driver. It shows per lot size whether a 2-axis lathe, a Swiss-type or a mill-turn machine is chosen.

## What is covered on the turning side?
- Rotational classification from the geometry, including multi-stepped mill-turn profiles.
- Turning, facing, grooving, thread turning, boring, drilling, reaming, tapping, cross-drilling on live tooling.
- Bar-stock sizing and cut-to-length on a saw class, or a purchased blank when the fleet has no saw.
- Fits and tolerances read from the drawing (ISO 286, ISO 2768) and bound to the feature they constrain.

## 2-axis, live-tool, Swiss-type or mill-turn?
| Machine class | Adds | Typical part | When it wins |
| --- | --- | --- | --- |
| 2-axis lathe | turning, facing, grooving, threading, boring | shafts, bushings, simple discs | no milled features; lowest hour rate |
| Live-tool turning centre | cross-holes, flats, keyways in the same clamping | shafts with pins and flats | any milled feature that would force a second machine |
| Swiss-type | guide bushing for long, slender parts | pins, needles, connectors below ~32 mm | length ≫ diameter, high volumes, tight runout |
| Mill-turn centre | full milling spindle, B-axis | complex housings from bar | several setups collapse into one; small lots of complex parts |

## FAQ
**How do I calculate the cost of a turned part?**
You need the stock the part consumes, the cuts it takes, and its threads and secondary features. You also need the machine-hour rate and the setup amortised over the lot. ARCNM does all of that from the STEP file and drawing, and shows the breakdown per operation.

**Does ARCNM handle Swiss-type and mill-turn parts?**
Yes. Swiss-type lathes and mill-turn centres are machine classes in your fleet. ARCNM compares them against a plain 2-axis lathe at every lot size. The lot-size curve shows which machine is chosen at each quantity.

**What about the material cost of a turned part?**
Material is priced from the bar or blank actually consumed, not from the finished volume. ARCNM uses your own material prices, each with an as-of date. So a price move in steel or brass shows up in the next calculation.