CNC-Fräse: Unterschied zwischen den Versionen

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{| class="wikitable" border="1" cellpadding="5" cellspacing="0" align="center"

|-

! From

! Variable

! Description

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! Formular

|-

| <math>~~f_z~~</math> || ~~Feed per Teeth~~ || ~~Vorschub pro Schneide~~ || <math>\text{mm}</math> ||

|rowspan="2"| '''milling cutter''' || <math>d</math> || Cutter diameter || Fräserdurchmesser || <math>\text{mm}</math>

|-

| <math>v_c</math> || Cutting Speed || Schnittgeschwindigkeit || <math>\frac{\text{m}}{\text{min}}</math> || ~~<math>v_c = \pi \cdot d \cdot n \cdot \frac{1}{1000}</math>~~

| <math>z</math> || Number of Teeth || Anzahl der Schneiden ||

|-

|rowspan="2"| '''material specific''' || <math>f_z</math> || Feed per Teeth || Vorschub pro Schneide || <math>\text{mm}</math> ||

|-

| <math>v_c</math> || Cutting Speed || Schnittgeschwindigkeit || <math>\frac{\text{m}}{\text{min}}</math> ||

|-

| <math>v_f</math> || Feed Rate Forward || Vorschub || <math>\frac{\text{mm}}{\text{min}}</math> || <math>v_f = n \cdot f_z \cdot z</math>

|rowspan="2"| '''calculated''' || <math>v_f</math> || Feed Rate Forward || Vorschub || <math>\frac{\text{mm}}{\text{min}}</math> || <math>v_f = n \cdot f_z \cdot z</math>

|-

~~| <math>z</math> || Number of Teeth || Anzahl der Schneiden ||~~

|-

| <math>n</math> || Revolutions || Umdrehungsgeschwindigkeit || <math>\frac{\text{1}}{\text{min}}</math>

| <math>n</math> || Revolutions || Umdrehungsgeschwindigkeit || <math>\frac{\text{1}}{\text{min}}</math> || <math>n = \frac{v_c \cdot 1000}{\pi \cdot d} </math>

|-

| <math>a_p</math> || Infeed || Tiefenzustellung || <math>\text{mm}</math>

|rowspan="2"| '''defined by process and<br>maximum load of machine''' || <math>a_p</math> || Infeed || Tiefenzustellung || <math>\text{mm}</math>

|-

| <math>a_e</math> || Sidewards Feed || Seitenzustellung || <math>\text{mm}</math>

|-

| ~~<math>d</math>~~ |~~| Cutter diameter || Fräserdurchmesser || <math>\text{mm}</math>~~

| '''for time considerations''' || <math>Q</math> || Material Removal Rate || Zeitspanvolumen || <math>\frac{\text{cm}^3}{\text{min}}</math> || <math>Q = a_e \cdot a_p \cdot v_f \cdot \frac{1}{1000}</math>

|-

| <math>Q</math> || Material Removal Rate || Zeitspanvolumen || <math>\frac{\text{cm}^3}{\text{min}}</math> || <math>Q = a_e \cdot a_p \cdot v_f \cdot \frac{1}{1000}</math>

|}

These values are connected to each other. There are two main formulars to calculate <math>~~v_c~~</math> and <math>v_f</math>.

These values are connected to each other. There are two main formulars to calculate <math>n</math> and <math>v_f</math>.

To have cutting speed in m/min instead of mm/min you need to divide by 1000.

A third formular gives you an estimation how much cm³ you can remove per minute, called <math>Q</math>.

Typically you choose a specific milling cutter for the job and lookup the values for the material. The process parameter are bound by the maximum load the machine can handle (See for example [[CNC-Fräse/Technical#Und_warum_kann_man_jetzt_keinen_Stahl_bearbeiten.3F|Why can't I mill steel in the CNC?]]) and of course by the workpiece you want to produce.

The cutting speed in the datasheet of a cutter is often calculated for a service time ("Standzeit") of 1 hour. That means if you mill with the exact parameters that are posted in the datasheet, the cutter will be unuseable after about one hour.