# CNC Tool Life Tracking Log Worksheet

> Source: https://netray.co/tools/cnc-tool-life-tracking-log-worksheet
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Free Tools

## Short answer

An editable log of tool life in parts and cutting minutes, with tool cost per part so you can set change intervals.

## Category

mes-shop-floor

## Industry

Machining

## Audience

- Machinist
- CNC programmer
- Tooling engineer

## Tool

**Kind:** worksheet

**Mode:** editable

**Currency:** $

**Columns:**

#### Tool

**Key:** tool

**Type:** text

#### Job

**Key:** job

**Type:** text

#### Material

**Key:** material

**Type:** select

**Options:**

- Aluminum
- Mild steel
- Stainless steel
- Alloy steel
- Titanium
- Cast iron
- Inconel
- Plastic

#### Parts per edge or tool

**Key:** parts

**Type:** number

#### Cut minutes per part

**Key:** mins

**Type:** number

**Format:** decimal

#### Cost per edge or tool

**Key:** cost

**Type:** number

**Format:** currency

#### Cutting minutes until change

**Key:** life

**Type:** number

**Expr:** parts * mins

**Format:** decimal

#### Tool cost per part

**Key:** cpp

**Type:** number

**Expr:** cost / parts

**Format:** currency

#### Reason for change

**Key:** reason

**Type:** select

**Options:**

- Flank wear
- Chipping
- Built-up edge
- Breakage
- Scheduled change
- Finish out of spec

**Rows:**

**Tool:** T1 face mill insert

**Job:** WO-104455

**Material:** Aluminum

**Parts:** 400

**Mins:** 0.9

**Cost:** 4.5

**Reason:** Flank wear

**Tool:** T2 12 mm endmill

**Job:** WO-104455

**Material:** Aluminum

**Parts:** 1500

**Mins:** 3.1

**Cost:** 62

**Reason:** Scheduled change

**Tool:** T3 CNMG insert

**Job:** WO-104510

**Material:** Stainless steel

**Parts:** 35

**Mins:** 2.4

**Cost:** 7.8

**Reason:** Flank wear

**Tool:** T4 drill 8.5 mm

**Job:** WO-104510

**Material:** Alloy steel

**Parts:** 220

**Mins:** 0.6

**Cost:** 38

**Reason:** Chipping

**Totals:**

#### Sum of tool cost per part

**Key:** cpp

**Agg:** sum

**Format:** currency

#### Average cutting minutes to change

**Key:** life

**Agg:** avg

**Format:** decimal

**Summary:**

#### Average tool cost per part across tools

**Key:** avg_cpp

**Expr:** sum_cpp / count

**Format:** currency

**Primary:** true

#### Average cutting minutes to change

**Key:** avg_life

**Expr:** avg_life

**Format:** decimal

**Notes:** Enter parts per edge for inserts or per tool for solid tools. Cutting minutes are in-cut time, not cycle time. Use this data to set change intervals in the control or tool management system.

## Content

**Intro:** Changing tools too early wastes money and changing them too late wastes parts. Logging how long each tool actually lasts, and why it was changed, turns tooling into a number you can manage.

**Sections:**

#### How to use the log

**Body:** Record each tool or insert type with the job and material, the number of parts it made and the cutting minutes per part. Enter the cost per edge or per tool. The worksheet calculates cutting minutes until change and tool cost per part. Add a reason for each change, since the reason tells you what to fix. Over a few jobs you can set a standard change interval and compare grades or speeds. Export to Excel to keep a running history.

#### Tool life and the Taylor relationship

**Body:** Tool life falls steeply as cutting speed rises. The Taylor equation expresses this as V times T to the power n equals a constant, with n depending on tool and work material. In practice, a modest speed reduction can multiply life while costing little cycle time, but the right trade depends on tool cost, machine rate and change time.

**Bullets:**

- Flank wear is the normal end of life and the basis for most intervals
- Chipping suggests interrupted cut, wrong grade or vibration
- Built-up edge points to low speed or the wrong geometry for the material
- Breakage points to feed, stick-out or workholding problems

#### Common mistakes

**Body:** A common error is tracking life in clock time rather than cutting time, which hides the effect of speeds. Another is mixing different grades or suppliers in the same row, so comparisons are meaningless. Count the cost of the change itself too: a cheap insert that stops the machine often can cost more than a better one that lasts. Write down what you changed whenever tool life moves.

**Cta:** If tool usage and cost should flow into ERP job costing, Netray can scope a read-only analysis. The log works by itself.

**Faq:**

#### What counts as tool life?

**Answer:** Commonly the minutes in cut until the tool reaches a wear limit or fails to hold tolerance. Some shops count parts instead, which is simpler and works when cycle conditions are stable.

#### How do I choose a change interval?

**Answer:** Take a conservative fraction of the typical life you have logged, so most tools are changed before wear affects parts. Revisit after a few jobs and adjust.

#### Can I use this for solid carbide tools?

**Answer:** Yes. Enter parts per tool and the full tool cost. Include regrind cost if you resharpen.

#### Why record the reason for change?

**Answer:** Different failure modes need different fixes: speed, feed, grade, coolant or fixturing. The reason column shows the pattern.

## Search terms

tool life log, cnc tool life tracking excel, insert life tracking sheet, cutting tool cost per part, tool change interval worksheet, tool wear log, cnc tooling cost tracking, tool life record template

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