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I've heard different names for the 'groove' that allows drill bits and driver bits to be used in a quick-change-type drill. For simplicity I'm referring to the thing labeled 'power groove' here.

Driver bit with a power groove.

I vastly prefer these because they're fast to change in and out. I need some brad point bits, and I discovered that they are not really available, as a large prepackaged set, with a power groove (or whatever you want to call it.)

Why is this? Is it just a quirk of the world that no one has made such a product? (And if there is one, please do point, the largest 'set' I've seen is a mere 5 piece compared to a 29 piece.)

Or is there something about these types of bits that is a compromise such that informed woodworkers know to avoid them and so such a product is not made.

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    Like you I have seen some drill bits which are contained within a quick-change-friendly 'sheathing', but a large prepackaged set of this type is probably asking too much. Remember that the larger bits would need to be stepped down (and considerably) which would greatly impact their strength and durability, may even fatally undermine anything wider than 1/4" or 6mm. And, not joking, how many holes are you drilling that this kind of speed is so important? If it seriously impacts your workflow, as it does with some pros, then you could do what they do and have separate driver and drill [contd]
    – Graphus
    Mar 14 at 10:01
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    ...so no changing is even required. Given the price of modern power tools this is now well within the reach of the weekend warrior or occasional woodworker/DIY enthusiast, and with occasional use even cheap units can last for many years with a bit of luck. Although I would hesitate to recommend this if you have to go cordless.... I mean powered cordless.... me on the other hand, most of my drills are Wheaties and coffee powered :-) I have somehow managed to acquire enough hand drills and braces that I can have a driver bit and countersink permanently installed in two of the 'spares'.
    – Graphus
    Mar 14 at 10:05
  • Probably worth noting that brad point bits are produced in smaller quantities than 'ordinary' metal/wood bits. That alone is going to be a slight disincentive to manufacturing. Mar 15 at 3:22
  • So Tom, if the apparent non-availability of what you're looking for is accurate have you thought of what direction you'd like to take instead? Are there larger sets of QC twist drills available for example? It's a bit of work (mostly in setup, not the execution) but you can convert twist bits to brad points if you have a Dremel or similar + cutting disks and the appropriate mandrel.
    – Graphus
    Mar 16 at 9:20
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These kinds of quick-change bits are very handy, but there is inevitably some slop in the fit; that is, if you place your finder on the drill tip you will probably be able be able to rock it slightly from side to side. This is never an issue when driving screws, as the conical shape of the screw driving into the wood prevents the screw from wandering, with the job of the driver merely to provide downward rotational force. But when drilling holes, even with a brad-point bit, it's essential that the point of the bit does not wander off-axis as this will result in an enlarged hole. In my experience these drill bits mounted to a hex shank do always wander. To save time using conventional cylindrical bits, a drill with a keyless chuck makes it quicker to change bits quickly.

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    Ditto, my experience of drill bits mounted in the quick-change 'shafts' is they do nearly invariably have lots of runout (and in one case bad enough that it simply couldn't be used). But it's not to do with the quick-change mechanism of the drill/driver since I don't own one, these were mounted in conventional Jacob's chucks or older chucks in manual drills. The flaw, in the ones I've had the displeasure of using at least, was in the way the bits were mounted into the hex portion. Which is a shame as it's a promising design for smaller bits (purely in terms of the surer grip on a hex shaft).
    – Graphus
    Mar 14 at 10:14
  • You're right - and I should also add that the ones I bought were very poor quality and snapped easily.
    – perlyking
    Mar 15 at 16:28

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