It’s meant for creating lightening holes of the type seen when building aircraft (or maybe just toolboxes and furniture that are built like WWII fighter planes). I’ve messed with trepanning tools, abrasive wheels, hole saws, and all manner of other stuff for cutting large holes in sheet metal. So far all of these tools are a painful nuisance. Typically, the hole is large and the sheet metal won’t fit on my CNC milling machine, so I’m left flailing. With this tool, you stick an endmill in a die grinder, put the grinder in the little fixture so it can pivot, drill yourself a pilot hole for the pivot, and away you go. Presumably you can switch it out for a little drum sanding attachment to debur the hole when done.
I like it!
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Recently updated on May 24th, 2023 at 04:33 pm

Bob is responsible for the development and implementation of the popular G-Wizard CNC Software. Bob is also the founder of CNCCookbook, the largest CNC-related blog on the Internet.
I like the extra elevation on that tool. Otherwise it’s just a variation of an adjustable hole cutter, available from most aircraft tools shops. They work fairly well for cutting sheetmetal or wood.
That’s a novel suggestion, as even though it is easy to cut large holes in sheet metal small holes can be a bit trickier. This is an ideal tip for aircraft construction.