What Size Drill Bit For #8 Screw

Drill bits are the cutting tools of drilling machines. They can be made in any size to order, but standards organizations accept divers sets of sizes that are produced routinely by drill bit manufacturers and stocked past distributors.

In the U.South., fractional inch and gauge drill bit sizes are in common employ. In nearly all other countries, metric drill bit sizes are most common, and all others are anachronisms or are reserved for dealing with designs from the U.s.. The British Standards on replacing guess size drill bits with metric sizes in the UK was first published in 1959.^{[ citation needed ]}

A comprehensive table for metric, fractional wire and tapping sizes can exist found at the drill and tap size chart.

Metric drill scrap sizes [edit]

Metric drill prepare, 1.0–half dozen.0 mm by 0.i mm, jobber length. The example that holds them in an indexed order (by size), via a graduated series of holes, is called a drill index.

Metric drill bit sizes ascertain the bore of the fleck in terms of standard metric lengths. Standards organizations define sets of sizes that are conventionally manufactured and stocked. For example, British Standard BS 328 defines 230 sizes from 0.ii mm to 25.0 mm.

From 0.2 through 0.98 mm, sizes are defined as follows, where N is an integer from 2 through nine:

• North · 0.i mm
• N · 0.one + 0.02 mm
• North · 0.1 + 0.05 mm
• Due north · 0.1 + 0.08 mm

From 1.0 through 2.95 mm, sizes are defined equally follows, where N is an integer from x through 29:

• N · 0.ane mm
• Northward · 0.1 + 0.05 mm

From iii.0 through 13.9 mm, sizes are defined as follows, where N is an integer from 30 through 139:

• North · 0.1 mm

From 14.0 through 25.0 mm, sizes are defined as follows, where M is an integer from 14 through 25:

• M · 1 mm
• M · 1 + 0.25 mm
• M · 1 + 0.5 mm
• M · 1 + 0.75 mm

In smaller sizes, bits are available in smaller bore increments. This reflects both the smaller drilled hole diameter tolerance possible on smaller holes and the wishes of designers to have drill bit sizes available within at near 10% of an capricious pigsty size.

The price and availability of particular size bits does not modify uniformly beyond the size range. Bits at size increments of 1 mm are most unremarkably available, and lowest price. Sets of $.25 in 1 mm increments might be establish on a marketplace stall. In 0.five mm increments, whatever hardware store. In 0.1 mm increments, any engineers' store. Sets are not commonly bachelor in smaller size increments, except for drill bits below ane mm diameter. Drill bits of the less routinely used sizes, such as 2.55 mm, would have to be ordered from a specialist drill fleck supplier. This subsetting of standard sizes is in contrast to full general exercise with number judge drill bits, where it is rare to find a attack the market which does not contain every gauge.

In that location are besides Renard series sequences of preferred metric drill bits:^[1]

• R5 (gene 1.58) : M2.5, M4, M6, M10, M16, M24
• R10 (factor 1.26): M3, M5, M8, M12, M20, M30

Metric dimensioning is routinely used for drill bits of all types, although the details of BS 328 apply but to twist drill $.25. For case, a set of Forstner bits may incorporate 10, xv, 20, 25 and 30 mm bore cutters.

Partial-inch drill bit sizes [edit]

Fractional-inch drill bit sizes are withal in common apply in the Us and in whatever manufactory (around the globe) that makes inch-sized products for the U.S. market.

ANSI B94.11M-1979 sets size standards for jobber-length straight-shank twist drill bits from ane/64 inch through 1 inch in i/64 inch increments. For Morse taper-shank drill bits, the standard continues in 1/64 inch increments up to 1¾ inch, then i/32 inch increments up to two¼ inch, 1/16 inch increments upward to three inches, ane/8 inch increments up to 3¼ inches, and a single ane/4 inch increment to 3½ inches. One aspect of this method of sizing is that the size increment between drill bits becomes larger equally bit sizes become smaller: 100% for the footstep from 1/64 to 1/32, but a much smaller percent between 1 47/64 and 1 3/4.

Drill bit sizes are written as irreducible fractions. So, instead of 78/64 inch, or 1 14/64 inch, the size is noted equally i vii/32 inch.

Below is a nautical chart providing the decimal-fraction equivalents that are most relevant to partial-inch drill bit sizes (that is, 0 to 1 by 64ths). (Decimal places for .25, .5, and .75 are shown to thousandths [.250, .500, .750], which is how machinists usually think about them ["two-fifty", "5 hundred", "vii-fifty"]. Machinists generally truncate the decimals later thousandths; for example, a 27/64" drill bit may be referred to in shop-floor speech equally a "4-20-1 drill".)

Charts like this, printed at affiche size, are widely posted on motorcar shop walls for handy reference past machinists as they piece of work. For some tasks information technology is faster and less abrasive to glance downwardly a column of numbers on a affiche than information technology is to dial computer buttons or practise penciled arithmetics.

For anyone looking to create such a affiche or to tailor the pattern and colors to their own preferences, spreadsheet software makes this fast and easy to practice. The tools that the software provides—formulas, cell formatting with rounding, autofill, and sorting by numerical order—obviate any transmission adding and information entry. For example, i tin can create the inch nominal rows for the chart—with columns for inch fraction, inch decimal, and corresponding millimeter decimal conversion—using formulas, prison cell formatting with rounding, and autofill; and ane can then create the metric nominal rows beneath that, with the inch decimal conversions existence provided by formula; and then 1 tin can sort the whole sheet past size club, automatically interposing the inch nominal and metric nominal rows by size lodge. Font and color can be chosen to make a poster-size chart that is piece of cake to read from i or 2 meters away. Printing tin can be done on a desktop printer, with the letter-size sheets then being stapled together to make upwards the larger poster.

Decimal-fraction equivalents [edit]

fraction in mm 1⁄64 0.015625 0.396875 ane⁄32 0.03125 0.79375 3⁄64 0.046875 1.190625 1⁄16 0.0625 ane.5875 5⁄64 0.078125 one.984375 3⁄32 0.09375 2.38125 7⁄64 0.109375 two.778125 1⁄eight 0.125 3.175 ix⁄64 0.140625 3.571875 five⁄32 0.15625 3.96875 eleven⁄64 0.171875 iv.365625 iii⁄16 0.1875 four.7625 thirteen⁄64 0.203125 5.159375 vii⁄32 0.21875 5.55625 15⁄64 0.234375 five.953125 1⁄4 0.250 6.350

fraction in mm 17⁄64 0.265625 vi.746875 9⁄32 0.28125 7.14375 19⁄64 0.296875 7.540625 5⁄sixteen 0.3125 7.9375 21⁄64 0.328125 8.334375 xi⁄32 0.34375 8.73125 23⁄64 0.359375 9.128125 iii⁄8 0.375 9.525 25⁄64 0.390625 9.921875 13⁄32 0.40625 ten.31875 27⁄64 0.421875 10.715625 vii⁄16 0.4375 xi.1125 29⁄64 0.453125 11.509375 15⁄32 0.46875 eleven.90625 31⁄64 0.484375 12.303125 1⁄ii 0.500 12.700

fraction in mm 33⁄64 0.515625 13.096875 17⁄32 0.53125 13.49375 35⁄64 0.546875 13.890625 ix⁄16 0.5625 14.2875 37⁄64 0.578125 fourteen.684375 nineteen⁄32 0.59375 fifteen.08125 39⁄64 0.609375 15.478125 5⁄eight 0.625 15.875 41⁄64 0.640625 16.271875 21⁄32 0.65625 16.66875 43⁄64 0.671875 17.065625 11⁄16 0.6875 17.4625 45⁄64 0.703125 17.859375 23⁄32 0.71875 18.25625 47⁄64 0.734375 18.653125 3⁄4 0.750 19.050

fraction in mm 49⁄64 0.765625 19.446875 25⁄32 0.78125 19.84375 51⁄64 0.796875 20.240625 13⁄16 0.8125 twenty.6375 53⁄64 0.828125 21.034375 27⁄32 0.84375 21.43125 55⁄64 0.859375 21.828125 7⁄eight 0.875 22.225 57⁄64 0.890625 22.621875 29⁄32 0.90625 23.01875 59⁄64 0.921875 23.415625 fifteen⁄sixteen 0.9375 23.8125 61⁄64 0.953125 24.209375 31⁄32 0.96875 24.60625 63⁄64 0.984375 25.003125 i one.000 25.400

Number and letter gauge drill bit sizes [edit]

Number drill bit guess sizes range from size 80 (the smallest) to size 1 (the largest) followed by letter gauge size A (the smallest) to size Z (the largest). Although the ASME B94.11M twist drill standard, for example, lists sizes as small as size 97, sizes smaller than 80 are rarely encountered in do.

Number and letter sizes are usually used for twist drill bits rather than other drill forms, as the range encompass the sizes for which twist drill bits are well-nigh oftentimes used.

The gauge-to-diameter ratio is not divers by a formula; it is based on—but is non identical to—the Stubs Steel Wire Guess, which originated in Britain during the 19th century.^[2] The accompanying graph illustrates the alter in bore with change in guess, too every bit the reduction in step size equally the gauge size decreases. Each step along the horizontal axis is 1 gauge size.

Number and alphabetic character gauge drill bits are still in common use in the U.S. and to a lesser extent the UK, where they have largely been supplanted by metric sizes. Other countries that formerly used the number series have for the most part as well abandoned these in favour of metric sizes.^{[ citation needed ]}

Drill bit conversion table [edit]

click to see a ruler comparing millimeters to fractions of an inch

gauge in mm 104 0.0031 0.079 103 0.0035 0.089 102 0.0039 0.099 101 0.0043 0.109 100 0.0047 0.119 99 0.0051 0.130 98 0.0055 0.140 97 0.0059 0.150 96 0.0063 0.160 95 0.0067 0.170 94 0.0071 0.180 93 0.0075 0.191 92 0.0079 0.201 91 0.0083 0.211 90 0.0087 0.221 89 0.0091 0.231 88 0.0095 0.241 87 0.010 0.254 86 0.0105 0.267 85 0.011 0.279 84 0.0115 0.292 83 0.012 0.305 82 0.0125 0.318 81 0.013 0.330 eighty 0.0135 0.343 79 0.0145 0.368

gauge in mm 78 0.016 0.406 77 0.018 0.457 76 0.020 0.508 75 0.021 0.533 74 0.0225 0.572 73 0.024 0.610 72 0.025 0.635 71 0.026 0.660 70 0.028 0.711 69 0.0292 0.742 68 0.031 0.787 67 0.032 0.813 66 0.033 0.838 65 0.035 0.889 64 0.036 0.914 63 0.037 0.940 62 0.038 0.965 61 0.039 0.991 sixty 0.040 one.016 59 0.041 i.041 58 0.042 1.067 57 0.043 1.092 56 0.0465 i.181 55 0.052 1.321 54 0.055 1.397 53 0.0595 1.511

approximate in mm 52 0.0635 1.613 51 0.067 1.702 fifty 0.070 1.778 49 0.073 ane.854 48 0.076 1.930 47 0.0785 ane.994 46 0.081 ii.057 45 0.082 two.083 44 0.086 two.184 43 0.089 ii.261 42 0.0935 two.375 41 0.096 2.438 40 0.098 two.489 39 0.0995 2.527 38 0.1015 2.578 37 0.104 2.642 36 0.1065 ii.705 35 0.110 2.794 34 0.111 2.819 33 0.113 ii.870 32 0.116 two.946 31 0.120 3.048 30 0.1285 3.264 29 0.136 3.454 28 0.1405 iii.569 27 0.144 three.658

guess in mm 26 0.147 three.734 25 0.1495 3.797 24 0.152 three.861 23 0.154 3.912 22 0.157 iii.988 21 0.159 four.039 20 0.161 4.089 19 0.166 4.216 xviii 0.1695 iv.305 17 0.173 4.394 16 0.177 4.496 15 0.180 4.572 14 0.182 4.623 13 0.185 four.699 12 0.189 4.801 11 0.191 4.851 x 0.1935 4.915 ix 0.196 4.978 8 0.199 5.055 7 0.201 5.105 6 0.204 5.182 5 0.2055 5.220 4 0.209 5.309 three 0.213 five.410 2 0.221 5.613 1 0.228 5.791

gauge in mm A 0.234 5.944 B 0.238 half-dozen.045 C 0.242 6.147 D 0.246 half-dozen.248 E 0.250 6.350 F 0.257 half-dozen.528 G 0.261 six.629 H 0.266 6.756 I 0.272 6.909 J 0.277 7.036 G 0.281 7.137 L 0.290 vii.366 M 0.295 7.493 Due north 0.302 7.671 O 0.316 8.026 P 0.323 viii.204 Q 0.332 eight.433 R 0.339 8.611 S 0.348 8.839 T 0.358 9.093 U 0.368 9.347 V 0.377 ix.576 W 0.386 ix.804 X 0.397 x.08 Y 0.404 10.26 Z 0.413 10.49

Screw-automobile-length drill [edit]

The shortest standard-length drills (that is, lowest length-to-diameter ratio) are spiral-machine-length drills (sometimes abbreviated S/M). They are named for their use in screw machines. Their shorter flute length and shorter overall length compared to a standard jobber scrap results in a more rigid drill flake, reducing deflection and breakage. They are rarely available in retail hardware stores or home centers.

Jobber-length drill [edit]

Jobber-length drills are the most commonly found type of drill. The length of the flutes is between 9 and 14 times the diameter of the drill, depending on the drill size. So a ane / 2  in (12.7 mm) diameter drill will exist able to drill a pigsty four+ 1 / 2  in (114.3 mm) deep, since information technology is 9 times the diameter in length. A one / 8  in (3.175 mm) diameter drill can drill a hole 1+ v / 8  in (41.275 mm) deep, since it is 13 times the bore in flute length.^[3]

The term jobber refers to a wholesale benefactor—a person or company that buys from manufacturers and sells to retailers.^{[ citation needed ]} Manufacturers producing drill bits "for the trade" (equally opposed to for specialized machining applications with detail length and design requirements) made ones of medium length suitable for a wide diverseness of jobs, because that was the type most desirable for general distribution. Thus, at the time that the proper noun of jobber-length drill bits became common, it reflected the aforementioned concept that names like general-purpose and multipurpose reflect.^{[ citation needed ]}

Aircraft-length drill [edit]

Extended-reach or long-series drills are ordinarily called aircraft-length from their original utilize in manufacturing riveted aluminum shipping. For $.25 thicker than a minimum size such equally ane⁄8 -inch (iii.175 mm), they are available in stock-still lengths such every bit six, 8, 12 or 18 inches (152, 203, 305 or 457 mm) rather than the progressive lengths of jobber drills.

11/32 inch drills: long-series Morse, manifestly Morse, jobber

The image shows a long-series drill compared to its diametric equivalents, all are eleven⁄32 inch (8.7313 mm) in diameter. The equivalent Morse taper drill shown in the center is of the usual length for a taper-shank drill. The lower drill scrap is the jobber or parallel shank equivalent.

Centre drill scrap sizes [edit]

Center drills, numbers one (bottom) through to 6 (summit)

Center drills are bachelor with two different included angles; 60 degrees is the standard for drilling center holes (for example for subsequent middle back up in the lathe), just ninety degrees is also mutual and used when locating holes prior to drilling with twist drills. Heart drills are made specifically for drilling lathe centers, simply are often used every bit spotting drills because of their radial stiffness.

Size designation Drill bore [inches (mm)] 5/0 0.010 in (0.254 mm) four/0 0.015 in (0.381 mm) 3/0 0.020 in (0.508 mm) two/0 0.025 in (0.635 mm) 0 one⁄32  in (0.794 mm) 1 three⁄64  in (1.191 mm) two five⁄64  in (ane.984 mm) three 7⁄64  in (2.778 mm) 4 1⁄eight  in (3.175 mm) iv½ 9⁄64  in (iii.572 mm) 5 3⁄xvi  in (iv.763 mm) 6 7⁄32  in (v.556 mm) vii 1⁄4  in (6.350 mm) viii 5⁄16  in (7.938 mm)

Gauge Body diameter [inches (mm)] BS1 1⁄8  in (3.175 mm) BS2 three⁄xvi  in (4.763 mm) BS3 ane⁄4  in (vi.350 mm) BS4 5⁄xvi  in (7.938 mm) BS5 7⁄16  in (xi.113 mm) BS5A 1⁄ii  in (12.700 mm) BS6 5⁄8  in (15.875 mm) BS7 3⁄4  in (xix.050 mm)

Spotting drill bit sizes [edit]

Spotting drills are available in a relatively pocket-sized range of sizes, both metric and imperial, as their purpose is to provide a precise spot for guiding a standard twist drill. Commonly bachelor sizes are 1/8", i/4", iii/8", 1/2", 5/8", iii/4", four mm, vi mm, 8 mm, 10 mm, 12 mm, 14 mm, 16 mm and 18 mm. The drills are most ordinarily available with either ninety° or 120° included angle points.

Meet likewise [edit]

• Drill and tap size chart

References [edit]

1. ^ Dasarathi-Cadem (ii Feb 2017). "Preferred sizes in engineering". CNC etc . Retrieved half dozen September 2017.
2. ^ Pöll, J. S. (June 1999). "The story of the gauge". Amazement. 54 (6): 575–581. doi:10.1046/j.1365-2044.1999.00895.ten. ISSN 0003-2409. PMID 10403873. S2CID 41519791.
3. ^ "Jobber Length Twist Drill Sizes".

What Size Drill Bit For #8 Screw,

Source: https://en.wikipedia.org/wiki/Drill_bit_sizes

Posted by: hemphilldaint1979.blogspot.com

Share this post