Twist Drill Bits - Longer Than Standard Ones

[Jim Eller]

It seems that every twist drill bit I can find is of a standard length and made basically for metal working. That works fine but I don't do much metal work. I woodworking I find they come up short on too many occasions. Especially the smaller diameters.

Is there some where I can find twist drill bits of a good quality and longer than standard twist drill bits?

Thanks,
Jim

[Brad Patch]

Search for extension drill bits that are used in the Aviation industry. They are about a foot long and are usually a high quality product.

[Jim Eller]

Thanks Brad. That is long!

I was thinking in terms of a couple of inches longer.

Jim

[Andy Bardowell]

Jim I thought I saw something called pen blank drilling bits at Lee Valley recently, they probably don't have a full range of sizes though.

[Stan Johnsey]

Lowe's has 'em, some about twice as long as a standard bit and some about a foot long.

[Mike Henderson]

Just a warning - the small long bits wander when drilling deep into wood, even if you use a drill press. For example, when drilling through a piece of wood, you think the bit's going to come out in one place and it comes out off that location.

For small holes, I find that drilling from each end to meet in the middle, while difficult to set up, works best when you need accuracy.

Mike

[Dave Verstraete]

Jim
"Taper Length" twist drills are the next step up from regular length.

[Jim Eller]

Jim
"Taper Length" twist drills are the next step up from regular length.

Dave,

"Taper" - That's probably the word I was looking for.

Thanks,
Jim

[Kevin Groenke]

Longer bits are going to have a tendency to deflect. I actually find I have want for shorter drill bits (screw machine) more often than longer. Full sets of atypical length bits will be fairly expensive.

From McMaster Carr:
http://www.mcmaster.com/#about-twist-drill-bits/=1ipubi

About Twist Drill Bits
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TWIST DRILL BIT STYLES
Specialty Drill Bits— Specialty drill bits include threaded shank twist drill bits and multi-diameter drill bits. See page 2393 (javascript:document.FrameworkASP.CtlgPgNbr.value= '2393';document.FrameworkASP.CtlgEdition.value='11 5';document.FrameworkASP.ReqTyp.value='CATALOG';do cument.FrameworkASP.submit();).
Reduced-Shank Twist Drill Bits— Called reduced shank because the shank diameter is smaller than the drill bit size (cutting diameter). They can drill holes that are larger than the capacity of the drill chuck. For example, our popular 1/2" shank diameter drill bits (also called Silver and Deming drill bits) can drill holes up to 1 1/2" dia. using drills with 1/2" capacity drill chucks. See pages 2394-2395 (javascript:document.FrameworkASPPgRange.RelatedCt lgPgs.value='2394,2395';document.FrameworkASPPgRan ge.CtlgPgNbr.value='2394';document.FrameworkASPPgR ange.CtlgEdition.value='115';document.FrameworkASP PgRange.ReqTyp.value='CATALOG';document.FrameworkA SPPgRange.submit();).
Short Length Twist Drill Bits— Also known as screw-machine and stub-length drill bits, they have a shorter flute and shorter overall length than jobbers' drill bits for maximum rigidity and accuracy, as well as reduced deflection and breakage. Great for hand and machine drilling. See pages 2396-2397 (javascript:document.FrameworkASPPgRange.RelatedCt lgPgs.value='2396,2397';document.FrameworkASPPgRan ge.CtlgPgNbr.value='2396';document.FrameworkASPPgR ange.CtlgEdition.value='115';document.FrameworkASP PgRange.ReqTyp.value='CATALOG';document.FrameworkA SPPgRange.submit();).
Maintenance Length Twist Drill Bits— Longer than short length drill bits for greater depth and shorter than jobbers' drill bits for increased rigidity. See page 2397 (javascript:document.FrameworkASP.CtlgPgNbr.value= '2397';document.FrameworkASP.CtlgEdition.value='11 5';document.FrameworkASP.ReqTyp.value='CATALOG';do cument.FrameworkASP.submit();).
Jobbers' Twist Drill Bits— The industry standard, jobbers' drill bits are the most widely used. They perform general purpose and heavy duty drilling with both portable and machine tools. We offer general purpose and heavy duty styles as well as deep-hole, left-hand, fast spiral, and slow spiral styles. We also have drill bits called aircraft jobbers' drill bits that are made to National Aerospace Standard (NAS) 907. See pages 2398-2408 (javascript:document.FrameworkASPPgRange.RelatedCt lgPgs.value='2398,2399,2400,2401,2402,2403,2404,24 05,2406,2407,2408';document.FrameworkASPPgRange.Ct lgPgNbr.value='2398';document.FrameworkASPPgRange. CtlgEdition.value='115';document.FrameworkASPPgRan ge.ReqTyp.value='CATALOG';document.FrameworkASPPgR ange.submit();).
Long Length Twist Drill Bits— Also known as taper length drill bits, have a longer flute and overall length than jobbers' drill bits for drilling deeper holes. See page 2409 (javascript:document.FrameworkASP.CtlgPgNbr.value= '2409';document.FrameworkASP.CtlgEdition.value='11 5';document.FrameworkASP.ReqTyp.value='CATALOG';do cument.FrameworkASP.submit();).
Taper-Shank Twist Drill Bits— Longer than most long-length drill bits, we offer taper-shank drill bits in diameters up to 2 1/2". They fit directly into the spindle hole of a drill press or other machine tool having the same spindle taper as the drill bit. For a drill press or machine tool with a larger spindle taper than the drill bit, you can use a reducing socket or sleeve. See page 2412 (javascript:document.FrameworkASP.CtlgPgNbr.value= '2412';document.FrameworkASP.CtlgEdition.value='11 5';document.FrameworkASP.ReqTyp.value='CATALOG';do cument.FrameworkASP.submit();).
Extra-Length and Extension Twist Drill Bits— With lengths from 6" to 18", these drill bits can drill extremely deep holes and reach 0deep spots. See pages 2410-2411 (javascript:document.FrameworkASPPgRange.RelatedCt lgPgs.value='2410,2411';document.FrameworkASPPgRan ge.CtlgPgNbr.value='2410';document.FrameworkASPPgR ange.CtlgEdition.value='115';document.FrameworkASP PgRange.ReqTyp.value='CATALOG';document.FrameworkA SPPgRange.submit();). HIGH-SPEED STEEL AND COBALT STEEL TWIST DRILL BITS
General Purpose High-Speed Steel— Works well on a variety of materials including steel, cast iron, and forgings. Most have a standard 118° point.
Heavy Duty High-Speed Steel— More rigid than general purpose drill bits, use them for hard steel, stainless steel, titanium, and other hard materials. All have a self-centering 135° split point that won't skid or walk when starting a hole—a distinct advantage for jobs on drill presses where bushings can't be used. The point also allows faster penetration and produces smaller chips for better chip evacuation.
Heavy Duty Cobalt Steel— More durable than heavy duty high-speed steel drill bits, cobalt steel drill bits retain their strength and hardness at higher temperatures. They are more abrasion resistant and can withstand the heat generated when drilling high-tensile alloys, stainless steel, titanium, Inconel, and other hard to machine metals. Some have a straw-gold or bronze oxide color for easy identification. Most cobalt drill bits feature the 135° split point that won't skid or walk when starting a hole. CARBIDE AND CARBIDE-TIPPED TWIST DRILL BITS
Carbide drill bits retain their hardness and sharp edge at higher temperatures than high-speed and cobalt steel drill bits, and have better abrasion resistance. Most carbide bit styles are used on abrasive materials such as cast iron, nonferrous alloys, hard rubber, plastics, glass, ceramics, and composites. For drilling steel, stainless steel, and high-temperature alloys, refer to our solid carbide straight flute, die, and high-performance drill bits.
We offer solid carbide drill bits as well as drill bits with carbide tips brazed to the end of a steel drill bit body. The advantage of solid carbide drill bits is their extreme rigidity, which results in greater drilling accuracy and an improved surface finish. Solid carbide drill bits also can be run slightly faster than carbide-tipped drill bits. When drilling with carbide, the machine setup must be as rigid as possible with no spindle vibration or end play. Using drill jig bushings is highly recommended. Whether you select a solid carbide or carbide-tipped drill bit depends on the material you're drilling and the economics of the application. See pages 2412-2419 (javascript:document.FrameworkASPPgRange.RelatedCt lgPgs.value='2412,2413,2414,2415,2416,2417,2418,24 19';document.FrameworkASPPgRange.CtlgPgNbr.value=' 2412';document.FrameworkASPPgRange.CtlgEdition.val ue='115';document.FrameworkASPPgRange.ReqTyp.value ='CATALOG';document.FrameworkASPPgRange.submit();) for carbide-tipped and solid carbide drill bits.
Note: The shank diameter is the same as the drill bit size (cutting diameter) on all of our solid carbide and carbide-tipped drill bits, except for solid carbide square-die, carbide-tipped drill bits for glass and ceramics, and small dia. bits with 1/8" shanks. SURFACE TREATMENTS AND COATINGS
Surface treatments and coatings improve the performance of drill bits.
Black Oxide— Also known as steam oxide or blue finish, this surface treatment has a dull, dark black or dark blue color. It retains lubricants for improved chip flow and increased abrasion resistance. It also relieves drill bit stress and provides additional tempering. Used on free machining steels, high temperature alloys, stainless steels, and cast irons. Note: Not recommended for most nonferrous materials.
Bright Finish— Surface is untreated. Polished flutes increase chip ejection in soft, ductile materials such as aluminum and other nonferrous materials. May also be used in ferrous metals, wood, and plastics where chips tend to cling to the tool surface.
Nitro-Carburizing— The surface treatment adds extra wear resistance along the cutting edge of the point. Drill bits also receive a low temperature stress relieving treatment for added lubricity. Drill bits will have a straw-gold or black and gold color.
Coatings— Coatings extend drill bit life by 300% to 800% compared to uncoated tools. Generally harder than the outer surface of the drill bit, coatings form a barrier against high temperatures and abrasion. They also improve the surface finish of parts and permit faster cutting speeds and feeds.
TiN (titanium nitride) coating is bright gold in color. It is for use on nonferrous and ferrous metals such as free machining steels, as well as nonmetallic materials and plastics. Drill bits with this coating may be used at speeds 50-75% faster than uncoated drill bits. Note: Not for use on wrought aluminum and titanium alloys.
TiCN (titanium carbonitride) coating is violet-gray or gun-metal gray or dark blue in color. It is intended for tough to machine steels, ductile cast iron, cast aluminum, stainless steels, high-temperature alloys, copper alloys, and titanium. Drill bits with this coating may be used at speeds 50-75% faster than uncoated drill bits.
TiALN (titanium aluminum nitride) coating is dark violet/blue-gray in color. Use for drilling stainless steel, high alloy carbon steel, and nickel-based high-temperature alloys. It's also highly effective for abrasive materials such as cast iron. Its high heat resistance may permit dry machining. Drill bits with this coating may be used at speeds 100% faster than uncoated drill bits.
Multilayer TiN/TiALN coating has a red-violet color. It has alternating ultrathin layers of coating that combine the universal applications of TiN, the shock resistance of TiCN, and the hardness and heat resistance of TiALN.

[Chris Friesen]

Lee Valley has some in HSS, but only in three sizes and they're not cheap.

http://www.leevalley.com/wood/page.aspx?c=1&p=40392&cat=1,180,42240