Metric Feed Rates

[Jim ..]

Hi every one,

I have a small problem getting the correct feed rate working from the feed and speed calculator in MC V9.0 sp1 Mill. I've read all the old post about the same subject, and can see I,m not alone, before I start- Yes my Material's are set to " mm " and Yes I have set my job setup to read Speed/Feeds from Materials.

Example 1: a material called P20 ( diemold Steel)

is set with Base Speed of 37 m/min 100% for contour work,100% for carbide cutter.

 

FPT=0.025 100% for End mill,100% for carbide.

= Spindle speed 1963rpm, Feed = 0.0

 

If you change the FPT to 0.026 you suddenly get the correct answer RPM=1963 Feed =204.152.

 

If you alter End mill setting to 75% say for a long series end mill the feed rate returns to 0.0 again.

This example changes for diferent FPT settings,

sometimes you will get the Feed lowering as you lower your FPT adjustment for Carbide to Hss cutters say 30% less, and would give the correct result, BUT go to 31% and the feed will goto 0.0 .

Could this be a problem with MC not reading enough zero's after the decimal point somwhere.

 

Thanks Jim.

[Fig sign]

Wellcome to the forum , Jim !

I did my own tools libraries with feeds and speeds for most common materials and never use calculator.

If I need to make calculations I simply write expressions like 3.14*80*12/1000 and after you input enter you will have a needed result.

Anyway I don`t like an idea of automatic speed and and feed calculation , the machinist knows what he needs .

 

[ 02-24-2003, 06:47 AM: Message edited by: plasttav ]