Ball End Mills: Single or Double-Ended?
Ball mills are great for machining that requires rounded or contoured finished products. They're available in a wide variety of sizes, coatings, and styles. The type of ball mill required will depend on many factors, such as the material being machined, the equipment being used, lubrication, and others. Another option that must be considered when looking into ball end mills is the number of cutting ends. They are available with a single cutting end and solid shank, or two cutting ends. So, what are the advantages to using a double-ended ball mill?
Cost Savings
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When manufacturers produce a single end ball end mill, they've already expended most of the time and effort it would take to make the mill double ended. It only requires a little more effort and resources to put another end on the single mill. For this reason, a double-ended mill is less expensive than two single-ended mills. Machinists can effectively purchase twice the tool for well under twice the cost. For high production facilities, these savings can add up very quickly. Having two cutting tools for much less than the (fraction of the) cost of buying two single end mills can provide a significant boost to the bottom line.
Space Saving
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Another benefit of double-ended ball end mills has to do with storage space. Shops that go through a lot of mills can find that the mills start to pile up. With two cutting ends, double-ended mills effectively take up half the space. Shops with limited storage will find that they have more room for other tools and materials. While ball mills don't take up a lot of space to begin with, cutting that space in half can still be beneficial to shops that put a premium on storage and organization.
Rapid Replacement
When a mill wears out, it can bring production to a standstill. Time must be taken to find and install a new mill before cutting can begin again. With double-ended mills, this happens half as often. When one end of the mill wears out, the machinist simply flips the mill around and cuts with the other end. Lost production time is lost money. If machinists can cut the time it takes to switch the mill in half, the business only loses half the production time.
The Right Machine
Double-ended mills aren't right for every milling machine though. They require slightly more clearance and tighter tolerances. Older machines may not be able to grip the tool properly, leading to irregular cuts and broken or chipped end mills. Since the shank end of a double-ended mill is fluted, there's less material to withstand lateral movement. Shops that make heavy, high-speed lateral cuts could risk breaking the shank of the mills.
Double vs. Single
The ball end mill that is chosen depends on many factors. With all of the options available, it's important to evaluate the intended use of the ball end mills and the machining equipment available before settling on a purchase. Single and double-ended mills both have advantages and disadvantages that must be weighed during evaluation.
Feel free to contact our experts here at Regal to get our professional advice on which tool is right for your application.