I've been easing into more and more metal work over the last year and half (propane art, collapsible fire fans and fire hula hoops a la Burning Man), so I drill a lot of multi-size holes in aluminum tubing. This is by far the best bit I've found for drilling through such thin materials. To get precise placement and a clean hole, normally I'd drill a small pilot hole, then run a larger drill bit in that hole to get the size and placement right. With this bit, I do not need to create a pilot hole (though, a center punch can help). I simply drill until I get to the right size (1/4" and 1/2" mostly). Because the bit has a single flute (cutting edge), it makes very clean holes. It's also very accurate: the bit is very stiff, so it wanders less when starting a hole. Since I don't need to change drill bits in my drill press to successively drill larger holes or change the jig I'm using to hold the part, it's become a real time saver.

-- Sean Rutledge

IRWIN Unibit
$14
(3/6" - 1/4")
Available from Amazon

$62
(three-piece set)
Also from Amazon

$67
(four-piece set)
Also from Amazon

Manufactured by IRWIN

Related items previously reviewed on Cool Tools:

The Complete Metalsmith

Panasonic Impact Driver

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