the spindle housing – introduces variables and opportunity for error. While it may be light cutting, not using tooling that is tailored for the job can have consequences. For example, I often find chamfering performed with 90 deg-tipped drills or standard end mills with a tilted axis. That’s a demanding ask for a tooling assembly that isn’t designed to efficiently strike an edge in that way: it requires slower cutting speeds that extend cycle times and make fine finishes difficult, it strains tool life and increases consumable costs, and it requires more cutting and thrust force that translate into more energy consumption and machine wear. So just how can a simple tooling change make for better performing and more economical chamfering operations? Let’s start with feed rate, because higher feed rates not only reduce cycle time, but subsequently address some of the other issues as well. Increasing cutting speed capability and the number of teeth are two ways that a tool’s design can increase feed rate. For example, our C-Cutter Mini uses up to four inserts. The diameter of its tool body is built to the lowest limits to optimize chipload and spindle speeds in chamfering small and large features. This allows for very fast cycles. The inserts themselves also play a key role, so much so that they are among the only inserts we design in-house: extremely sharp edges with three types of coating reduce cutting
resistance to help address speed, finish and force concerns that can arise, even on chamfers that require the tool’s maximum size capabilities. In testing, this tool measured feed rates that were three times faster and a machining time that was less than 1/6 of a two- tooth alternative product. The versatility of chamfering tools can be impactful in key areas, too. Their capability to perform different types of processes, or even consolidate them, pays significant dividends. In this case, the C-Cutter Mini’s unique design and proprietary four-edged inserts allow users to back or front chamfer without dramatic setup changes. In another scenario where the proper tool selection pays off, let’s say you have a part with 10,000 holes that all need to be chamfered. I see shops who think they are saving time by using a 90 deg chamfer to pilot. But when a deep hole drill with an angle of 140 deg has to enter a 90 deg hole, that’s not really piloting. The corners want to rip off. The sporadic life of high-performance drills can often be attributed to this. A better tooling choice would be something like our double- degree Sphinx spot drill with a 142 deg angle that blends into a 90 deg angle up top. You’re giving that drill somewhere to enter without running it into a 90 deg angle. Not only does it combine and accelerate processes, but you’re
for one of the biggest companies in the world. Most machinists likely think of chamfering as just another finishing step to get through before moving a part out the door. However, this episode in consumer electronics history is the perfect illustration of the importance of consistently angled or rounded edges. As an operation that’s performed on nearly every workpiece, there is (of course) the safety concern of sharp edges, but there’s a growing demand for fine finishes and feel in a myriad of applications that only precision chamfering can deliver. There’s no doubt that I see shops dedicating more thought and time to this process. But when it comes to the tooling being used, they’re often still trying to fit a square peg into a round hole, relying heavily on the accuracy of the machine instead of using a setup meant for the job. As we know, each component – from the cutting edge all the way back to
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