Machinists ask me all the time, “When do I go fast and when should I go slow with a single flute end mill?” Well, as you can imagine, there are a lot of variables at play regarding feed rates for single flute end mill, but let’s try to break it down.
I’ll use one tool for reference, but the results should be easily scalable amongst the rest of our tools. Let’s say you’re using a DATRON 68806K Single Flute End Mill (aka. 4-in-1 wiper flat) to machine a piece of 6061 aluminum. There is a variety of jobs you can accomplish with this tool, but each will have a different feed for a different reason.
Slow Feed Rates for Single Flute End Mill
Slow (60″/min) – 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 for Single Flute End Mill
Medium (120″/min) – Slotting – Something a single flute does particularly well is slotting, which is a tool path that has 100% of the tool diameter engaged in the material. Using a proper depth cut (25% of tool diameter), you can cruise along at a decent pace without worrying about clogging up on chips.
Fast Feed Rates for Single Flute End Mill
Fast (180″/min) – Traditional Roughing – When you are using a normal milling strategy, in the range of 33-50% depth of cut (2-3mm) with a 50-70% stepover, you can be fairly safe kicking the speed up, just keep an eye on your spindle load.
Very Fast Feed Rates for Single Flute End Mill
Very Fast (240″/min) – 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% depth of cut (6-12mm) with this strategy because our stepover would be decreased to 10-20%. 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 for Single Flute End Mill
Extremely Fast (300″/min) – Shallow roughing – If you are taking off less than 10% 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.