In a blog (click here to view), Dann Demazure, applications engineer at Datron Dynamics, wrote: Machinists ask me all the time, “When do I go fast and when should I go slow with a single-flute endmill?” Well, as you can imagine, there are a lot of variables at play regarding feed rates for single-flute endmills, but let’s try to break it down.
Let’s say you’re using a single-flute endmill to machine a piece of 6061 aluminum. There are numerous jobs you can accomplish with this tool, but each will have a different feed for a different reason.
Slow Feed Rates
Slow is 60 ipm for finishing. If you need an exceptional quality in the finish of a floor or wall, it helps to slow the machine down to take a fine chip and decrease cutter load/cutter deflection.
Medium Feed Rates
Medium is 120 ipm for slotting. Something a single flute does particularly well is slotting, which is a toolpath that has 100 percent of the tool diameter engaged in the material. Using a proper depth cut (25 percent of tool diameter), you can cruise along at a decent pace without worrying about clogging up on chips.
Fast Feed Rates
Fast is 180 ipm for traditional roughing. When you are using a normal milling strategy, in the range of 33-50 percent depth of cut (2-3mm) with a 50-70 percent stepover, you can be fairly safe kicking the speed up, just keep an eye on your spindle load.
Very Fast Feed Rates
Very fast is 240 ipm for trochoidal roughing. If you are using Mastercam (Dynamic milling) or Fusion 360 (Adaptive clearing), you may have heard of this strategy before. Instead of going about the traditional method, this method utilizes more of the flute to boost efficiency. For instance, we could use 100-200 percent depth of cut (6-12mm) with this strategy because our stepover would be decreased to 10-20 percent. In many cases, this prolongs the life of the tool and puts less strain on the spindle, so you can safely bump the feed rate up.
Extremely Fast Feed Rates
Extremely fast is 300 ipm for shallow roughing. If you are taking off less than 10 percent depth of cut (0.60mm), then you should be safe cranking the feed way up. With such a shallow cut, you won’t have to worry about overloading the tool or spindle.
Related Glossary Terms
- depth of cut
depth of cut
Distance between the bottom of the cut and the uncut surface of the workpiece, measured in a direction at right angles to the machined surface of the workpiece.
- endmill
endmill
Milling cutter held by its shank that cuts on its periphery and, if so configured, on its free end. Takes a variety of shapes (single- and double-end, roughing, ballnose and cup-end) and sizes (stub, medium, long and extra-long). Also comes with differing numbers of flutes.
- feed
feed
Rate of change of position of the tool as a whole, relative to the workpiece while cutting.
- gang cutting ( milling)
gang cutting ( milling)
Machining with several cutters mounted on a single arbor, generally for simultaneous cutting.
- inches per minute ( ipm)
inches per minute ( ipm)
Value that refers to how far the workpiece or cutter advances linearly in 1 minute, defined as: ipm = ipt 5 number of effective teeth 5 rpm. Also known as the table feed or machine feed.
- milling
milling
Machining operation in which metal or other material is removed by applying power to a rotating cutter. In vertical milling, the cutting tool is mounted vertically on the spindle. In horizontal milling, the cutting tool is mounted horizontally, either directly on the spindle or on an arbor. Horizontal milling is further broken down into conventional milling, where the cutter rotates opposite the direction of feed, or “up” into the workpiece; and climb milling, where the cutter rotates in the direction of feed, or “down” into the workpiece. Milling operations include plane or surface milling, endmilling, facemilling, angle milling, form milling and profiling.
- slotting
slotting
Machining, normally milling, that creates slots, grooves and similar recesses in workpieces, including T-slots and dovetails.
- toolpath( cutter path)
toolpath( cutter path)
2-D or 3-D path generated by program code or a CAM system and followed by tool when machining a part.
