Speed rate and feed rate – How to find the right cutting data
Speed and feed calculator, formulas & Co
Acrylic glass, wood, carbon or plastics – each material must be processed with a suitable end mill for the result to look as good as the idea. In addition, the speed and feed rate need to be adjusted accordingly. You will quickly gather your own empirical values, but there are also specific formulas for calculating the speed rate and other values. The easiest way is to use the free STEPCRAFT Milling Calculator. You can find it in the App Store and the Play Store. Simply select your machine, your material and your end mill and the STEPCRAFT Milling Calculator will show you the appropriate speed rate and cutting data in no time.
End mills and their CNC applications
|
Type of tool |
Characteristics |
Applications |
|
End mill 2-flute fish (downcut) |
for thin material very clean cutting edges |
plastic wood |
|
End mill 2-flute fish (upcut) |
universal end mill good immersion capacity |
wood non-ferrous metals plastic |
|
End mill diamond toothed |
high endurance |
GFK CFK PCB |
|
End mill spiral toothed (downcut) |
for thin material very clean cutting edges |
softwood plywood |
|
End mill spiral toothed (upcut) |
chipbreaking |
softwood plywood |
|
End mill radius |
finishing cutter 3D carving |
wood non-ferrous metals plastic |
|
End mill single flute |
low friction large flute |
low-melting plastics |
|
V-bit |
single flute |
universal PCB engravings |
Benchmark for Speed and Feed
|
ø Cutting Speed m/min.* |
End Mill Diamater |
|||||||||
|
ø 1 mm |
ø 2 mm |
ø 3 mm |
ø 4 mm |
ø 5 mm |
ø 6 mm |
ø 8 mm |
ø 10 mm |
ø 12 mm |
||
|
Feed Rate in mm / Tooth / Revolution |
||||||||||
|
Cast Aluminum > 6 % Si |
200 |
0,010 |
0,010 |
0,010 |
0,015 |
0,015 |
0,025 |
0,030 |
0,038 |
0,050 |
|
Wrought Aluminum Alloy |
500 |
0,010 |
0,020 |
0,025 |
0,050 |
0,050 |
0,050 |
0,064 |
0,080 |
0,100 |
|
Soft Plastic |
600 |
0,025 |
0,030 |
0,035 |
0,045 |
0,065 |
0,090 |
0,100 |
0,200 |
0,300 |
|
Hard Plastic |
550 |
0,015 |
0,020 |
0,025 |
0,050 |
0,060 |
0,080 |
0,089 |
0,100 |
0,150 |
|
Hard Wood |
450 |
0,020 |
0,025 |
0,030 |
0,055 |
0,065 |
0,085 |
0,095 |
0,095 |
0,155 |
|
Soft Wood |
500 |
0,025 |
0,030 |
0,035 |
0,060 |
0,070 |
0,090 |
0,100 |
0,110 |
0,160 |
|
MDF |
450 |
0,050 |
0,070 |
0,100 |
0,150 |
0,200 |
0,300 |
0,400 |
0,500 |
0,600 |
|
Brass, Copper, Bronze |
365 |
0,015 |
0,020 |
0,025 |
0,025 |
0,030 |
0,050 |
0,056 |
0,065 |
0,080 |
|
Steel |
75 |
0,010 |
0,010 |
0,012 |
0,025 |
0,030 |
0,038 |
0,045 |
0,050 |
0,080 |
*The stated cutting speeds are average values. In result of the milling process and the type of end mill adjustments might be necessary .Roughing: Reduction of up to 25 % – Finishing: Increase of up to 25 % – HSS end mill: Reduction of up to 50 % (hard materials) – VHM end mill: Increase of up to 25 %
Cooling / Lubricating
The cooling of non-ferrous metals occurs in best case with a lubrication system in combination with lubricant. Furthermore, the lubricating improves the surface quality and the service life of the tool. Lubricating with soap solution is suitable on acrylic glass. This improves an excellent surface.
Downcut Milling
In downcut milling, the end mill pulls itself into the workpiece, which can lead to the gantry or the Z-axis beeing pulled uncontrolled (backlash of lead screw) in the direction of the workpiece during the removal of larger chips. This causes a less precise milling pattern and can even result in the breakage of the end mill, if the chip building is too large.
Assuming backlash-free ball screws are used, the downcut is preferred over the upcut milling.
Upcut Milling
During upcut milling, the end mill pushes away from the workpiece, which, when only removing little chips, quickly causes the cutting edge to push out of the workpiece. This leads to chatter marks which create an unclean surface and reduce the endurance of the end mill.
The upcut milling is favored on machines with threaded lead screws which contain backlash.
Relief-grinded End Mills
The maximum possible infeed is usually reduced to the spiral length of the end mill, otherwise the shank will rub on the workpiece. Due to the relief-grinded shank, depths over several infeeds up to the maximum effective lengths are possible, thus, exceeding the spiral length.
increasing lube
Dependence of lubrication system on production process
Milling
Drilling
Grinding
Lapping
Turning
Grating
Honing
increasing material qualification
Suitability of lubrication system for cutting materials
Cu Alloy
Al Casting Alloy
Steel ferritic
Mg Alloy
Wrought Aluminum Alloy
Pearlitic
Cast Iron
Stainless Steels