Choosing a set of drill bits

I have a couple left hand bits that started out right handed, of course they don't have any relief on the lands either. they showed up in boxes of miscellaneous "good stuff" during "Saturday morning shopping"
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Gouge a hole in some hardwood with the gouge in question. Add some diamond paste to the hole. Replace the gouge in the hole and hone. Profiled rubber sanding forms can be handy for this, too.
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Reply to
Larry Jaques
I haven't tried the HF ones, but I have a set of cobalt steel number-sized bits (with split points), and find them excellent. Whenever I need to replace a bit from the HHS Cleveland bits in my 115 bit set, I order individual cobalt steel with split point.
I don't expect a drill doctor (certainly not mine, which is one of the early ones of that name) to do a proper job making a split point on smaller bits (e.g. 3/16" or smaller), but I vastly prefer the behavior of cobalt steel with split points to standard chisel-point bits.
If I could afford it, I would get the full 115 bit set in quality Cobalt steel with split points. As it is, the bits which get worn out most rapidly do get replaced with the Cobalt with split points.
If I need to sharpen one from 1/4" down, *without* split point, I've got an antique DuMore drill sharpener which does an excellent job on chisel points from 1/4" down to #70.
BTW If you have gotten an index with a 115 bit set, and the index is made by Huot (generally the best index brand that I have found), look carefully in the section for the fractional size bits, and you will see a spring clip on the angled divider. If you have wondered what that clip is for -- get a Huot index for #61-#80 bits and it clips in there so your 115 piece set becomes a 135 piece set. :-)
That is pretty bad. I've bought inexpensive 115 bit sets (TiN coated) and discovered that some of them are sharpened backwards. (This aside from ones which jam during the drilling in steel and suddenly acquire a reverse twist. :-)
And I've added my personal experience above.
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Making me wonder just how variable the sets are -- and how good your luck is. Perhaps you just bought each on a very good day. :-)
A pity I don't have a sharpener which can put a *good* split point on the smaller bits. I've tried it with my older Drill Doctor, and once brought to a meeting where someone else who had good split point luck with his brought his as well. We both brought sample bits, too. It turns out that his good experience was with bits say 5/16" or larger, and my bad experience was with bits 3/16" and smaller. Same results with both drill doctors. :-)
So -- I use the DuMore (with its set of point steadying collets) to get a good chisel point on bits -- (even those which started out with a good split point before dulling too far to use), and that is typically enough to get a project completed -- until I get an order of a half dozen or dozen cobalt steel split point bits to replace them. :-) A pity that the DuMore can't handle bigger than 1/4" bits. :-(
I started out in the 115 bit index with ordering 1/4", 3/8" and 1/2" in cobalt split point as replacements -- even before those got dulled. :-)
Good Luck, DoN.
Reply to
DoN. Nichols
I don't own a Drill Doctor, but some day I hope to own a decent tool and cutter grinder. For now I hand grind drill bits on the bench grinder. Often my grinds are more effective than the factory grind on high dollar known name drills. I'm not good enough that I put any of my hand grinds into one of the CNC mills and just "trust" them. For shallow prespotted holes they are okay. That being said I can take a little more care and get a decent hand grind. I can also split the point with a rotary hand piece and a small abrassive wheel. I'm not as good at that, but again if I take care I can do an okay job. The biggest help to me was a magnifying lamp mounted on my work bench near the bench grinder. I'll swing it over the grinder to put the primary grinds on, and then over the vise where I can split the point. When I feel good and with a little luck I've used my hand ground split point drills to deep drill stainless for things like stainless steel pen bodies. 3/16 is also about my limit, but in a pinch I have done drills freehand as small as #21. #21 is a common size I use all the time for 10-32 threaded holes. I try to keep fresh clean new spares, but it doesn't always happen.
FYI: I usually do a 3 facet grind, but I can do a round fall away grind as well. The 3 facet grind is easier and faster. Particularly with badly damaged drills.
Smaller drills I usually just throw away and replace. They are cheap.
Reply to
Bob La Londe

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