Drill
Bits, Countersinks, Reamers &
Counterbores
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Drill Bits,
Left-hand
Drill Bits,
Long Boy,
Silver & Deming,
Metric,
Tapered Shank,
Drill Bit
Gauges,
Sharpeners,
Center Drill Bits,
Stepped Drill Bits,
Circle Cutter,
Countersinks,
Reamers,
Floating Reamer Holder,
Taper-pin Reamers,
Counterbores,
Engraving Bits,
Combo Drill-Tap Bits,
Diamond Wheels,
Wood bits,
Masonry Bits
Drilling a hole through metal is one of the most basic machining tasks.
However, there are many interacting variables associated with
successful execution thus
requiring careful consideration of: the
material to be drilled, rigidity of the setup, depth of hole,
bit design, bit material, bit sharpness, bit length, RPM,
feed rate, chip removal,
heat, &
lubrication.
Refer to
how to drill a hole
tutorial &
how to drill the center of a rod.
Also see Hand Drills &
Drill Presses Sections.
Tables
Metric & Inch Equivalents
Inch
to Millimeter Conversion Table
Millimeter to Inch Conversion Table
Decimal
Equivalents of 8ths, 16ths, 32nds,
64ths
Decimal
Equivalents of Letter Size Drills
Decimal
Equivalents of Number Size Drills
American
Standard Pipe Thread & Tap Drill
Sizes
Tap Drill Sizes For Fractional Size
Threads
Millimeter
Tap Drill Sizes
National /Unified Coarse/Fine Thread
Dimensions & Tap Drill Sizes
Cutting Speeds & Feeds for Drills
Drill Bits
Set of USA made fractional (1/16" to 1/2" by 1/64"),
numbered
(1-60) & lettered (A-Z) jobber-length
HSS drill bits.
Set of HSS micro-drill bits (import) numbered 61 to 80.
In general, the smaller the drill bit, the higher
the required RPM.
Clear the chips frequently.
Sets of USA made fractional, numbered & lettered
(Cleveland Forge) stub-length
HSS drill bits.
The short stub drill bits afford reduced
flexing & aid use in tight areas.
Set of
Dewalt fractional, pilot-point, jobber-length
drill bits (Germany).
The shanks have three
flat sides for enhanced chuck gripping.
These split-point bits work nicely on a lathe.
Polished (bright finish): Polished
drills do not have a
coating which helps increase chip flow in soft materials.
For use in aluminum, wood, & plastic. Titanium Nitride
(TiN) gold color: Multi-purpose coating that increases tool
life & performance.
Hardness & heat resistance allows
running at higher speeds & feeds
(25% higher than uncoated).
Black Oxide surface
treatment: Retains
lubricants to aid in
wear resistance & chip flow.
Do not
use in non-ferrous
materials.
Left-hand Drill Bits
Left-hand HSS drill bit set,
135 deg split-point design,
used to drill a hole in a broken screw or bolt to
extract it.
Sizes: 1/4", 15/64", 7/32", 13/64", 3/16", 11/64",
5/32", 9/64",
1/8", 7/64", 3/32",
5/64", & 1/16".
Left-hand split-point
1/4"
cobalt
steel drill bit. Run drill in reverse.
Drill extraction set that has left-handed, split-tip
cobalt drills for harder
materials (USA).
Long Boy Drill Bits
Eight-inch, black
oxide, HSS long boy
drill bit set 1/8" to 1/2" by 1/64" (import).
The drill bit stand is by Huot (USA).
Silver & Deming (S&D)
Set of 8, 9/16" to 1"
by 1/16" Silver & Deming HSS
drill bits with 1/2" shanks (USA) in a
Huot drill bit index.
Clamped parts & low RPM with the proper cutting
fluid are required for
successful large-bit hole drilling.
Set of 33,
1/2" to 1" by 1/64"
Silver & Deming HSS drill
bits with 1/2" shanks (import) in a Huot drill storage stand.
I recommend using 3/4" shank S&D drill bits
on large, powerful
machines like a Bridgeport.
This stand is heavy-duty due to the
overall
weight of holding so many large drill bits.
Set of eight, 1-1/16"
to 1-1/2" by 1/16" Silver &
Deming HSS drill bits with 1/2" shanks (import).
The chisel edges (bit geometries)
for these bits are
large thus causing chatter & wandering when drilling metal.
Pre-drill the hole with a bit slightly larger than the chisel
edge. Then, just
the cutting lip will smoothly drill the hole.
Use low RPM & adequate amounts of the appropriate cutting oil.
The stand uses
1/4-28 x 2-1/4"
bolts, with tube spacers,
threaded into the upper plate. Bolt heads act as feet.
1-1/2" mounted drill bit in RF-25
mill.
1.5" drilled hole through a
1/4" cold-rolled steel plate.
Stands afford high-density
storage for drill
bits, transfer punch, & transfer screw sets.
Tapered Shank
Long drill bits having MT2 shanks with tang (import)
for use
in lathe tailstock or
floor drill press.
Sizes are 1/2", 9/16", 5/8", 11/16" & 3/4".
These are black-oxide treated HSS.
Metric Drill Bits
Set of 1mm to 13mm by 0.5mm,
jobber-length, HSS metric drill bits (USA).
Set of
51, 1mm to 6mm by 0.1mm, jobber-length,
TiN coated HSS metric drill bits in
a steel index.
Set of
50, 1mm to 5.9mm by 0.1mm, jobber-length,
HSS metric drill bits in a Huot index
(mixed manufacture).
Set of
41, 6mm to 10mm by 0.1mm,
jobber-length, HSS metric drill bits in a Huot index.
Micro-drill bit set (carbide). Size
marked on the plastic
collar which also acts as a depth stop for setup
repeatability.
Drill Bit
Gauges
Fractional, numbered, & metric
drill bit gauges.
Metric drill bit gauge 1mm to
13mm by 1/2 mm made out
of 1/4" aluminum plate. A 1/4" hole is on the far right end.
SharpenersSharpeners
Low-cost, all metal drill bit sharpener that uses a
bench grinder.
Dress the grinder wheel
before use.
Grinding attachment manual.
The Drill Doctor 750X
uses a 180 grit diamond wheel to sharpen drill bits (manual).
This model affords variable grinding control over several important
bit geometries
such as point angle, chisel & relief angles, split-point & amount of material
removal.
Use their highest grit diamond wheel available though a
higher grit would be better.
All bit grinders require careful, fine
adjustments & a consistant delicate touch.
Drill bit stop-collar set to control
hole depth & afford
repeatability.
Split-ring design drill bit
stop collars securely clamp OD.
Sizes: 1/8", 3/16", 1/4", 5/16",
3/8", 7/16", &
1/2".
Drilled holes are for
clearance.
The resulting hole
size
is often larger than the drill bit &
may not be perfectly round.
Precision holes are either
reamed,
ground, or
bored.
Center Drill Bits
Different
center drill bit (plain type) sizes. KEO is a quality, brand name.
Left to right: #6, #5, #4-1/2, #4, #3, #2, #1, #0. The long, 4" bit is a #2.
CENTER DRILL BIT SIZES | ||||||||
BODY DIAMETER | DRILL BIT DIAMETER | DRILL BIT LENGTH | OVERALL LENGTH | |||||
# | inches | mm | inches | mm | inches | mm | inches | mm |
0 | .0938 | 2.39 | .0312 | 0.79 | .0380 | 0.97 | 1.125 | 29 |
1 | .1250 | 3.18 | .0468 | 1.19 | .0468 | 1.19 | 1.250 | 32 |
2 | .1875 | 4.76 | .0781 | 1.98 | .0781 | 1.98 | 1.875 | 48 |
3 | .2500 | 6.35 | .1093 | 2.78 | .1093 | 2.78 | 2.000 | 51 |
4 | .3125 | 7.94 | .1250 | 3.18 | .1250 | 3.18 | 2.125 | 54 |
4-1/2 | .3750 | 9.53 | .1406 | 3.57 | .4063 | 10.32 | 2.500 | 64 |
5 | .4375 | 11.11 | .1875 | 4.76 | .1875 | 4.76 | 2.750 | 70 |
6 | .5000 | 12.70 | .2187 | 5.56 | .2187 | 5.56 | 3.000 | 76 |
Proper
center drill bit depth to
accommodate lathe tailstock center.
Stepped Drill Bits
Unibit
stepped drill bits
are excellent for thin
materials. See
Unibit packaging information.
Metric Stepped Drill Bit Set
Metric sized five piece step drill bit set having
HSS split-point with cobalt coating, two flutes, & tri-flat shank.
Metric sizes: 1 Pc, 10mm shank step bit, 13 steps from 6mm to 35mm x 6, 8,
10, 13, 16, 18, 20, 22, 25, 28, 30, 32, 35mm;
1 Pc, 8mm shank step bit, 10 steps from 4mm to 22mm x 2mm; 1 Pc, 8mm shank
step bit, 7 steps from 6mm to 18mm x 2mm;
1 Pc, 6mm shank step bit, 9 steps from 4 mm to 12mm x 1mm;
1 Pc, 6mm shank step bit, 5 steps from 4mm to 12mm x 2mm.
Lightweight aluminum storage case included.
The angled shape of each step can be
used to chamfer the hole's sharp edge.
Circle Cutter
Adjustable, large hole cutter that uses a HSS tool bit
(USA).
1/2" shank & replaceable 1/4" pilot drill bit.
Cuts sheet metal, brass, copper, aluminum,
plastic, wood & composition
materials.
It has an inches scale that adjusts for diameters
from 1-3/4" to 7-7/8". 500 RPM
maximum.
General No. 55 circle
cutter instructions.
Countersinks
A Weldon zero-flute 82
deg
countersink set (USA).
The
one center/rear countersink is 100 deg & is used
for
flat-head screws when fastening thin sheet metal.
These
no-chatter countersinks
also
deburr holes very well.
They can be sharpened from inside the hole with
a
fine round stone or
diamond file
but these
excellent countersinks have, so far, not required
any maintenance even after heavy use
in mild steel.
The (above) USA manufactured countersinks
are superior to most import
counterparts.
KEO, Weldon,
M.A. Ford, & Irwin are all excellent
countersinks.
Low-cost
bits invariably chatter.
Chamfer - a cut that is made in material, usually at a 45 deg angle to the adjacent principal faces.
Bevel - usually larger, slanted surface but sometimes used interchangably with chamfer.
Countersink - a conical hole cut into a manufactured object, or the
cutter used to cut such a hole.
A common use is to allow the head of a
countersunk bolt, screw or rivet, when
placed in the hole, to sit flush with
or below the surface of the surrounding material.
Counterbore - a cylindrical, flat-bottomed hole that enlarges
another coaxial hole, or the cutter
used to create such a hole. A counterbore hole
is typically used when a
fastener, such as a socket head cap screw, is
required to sit flush with
or below the level of a workpiece's surface.
Different countersink angles to match bolt head.
100 degs & above are
good for thin sheet metal.
60 deg, 82 deg, & 90
deg
zero-flute countersink sets.
60, 82, 90 deg ZERO-FLUTE COUNTERSINK SPECIFICATIONS | |||
SIZE | DIAMETER CUTTING RANGE (in) | SHANK DIAMETER (in) | |
0 | 1/16 ~ 15/64 | 0.0625 ~ 0.2344 | 1/4 |
1 | 5/32 ~ 13/32 | 0.1563 ~ 0.4063 | 1/4 |
2 | 3/16 ~ 17/32 | 0.1875 ~ 0.5313 | 1/4 |
3 | 5/16 ~ 25/32 | 0.3125 ~ 0.7813 | 1/2 |
4 | 9/16 ~ 1-3/32 | 0.5625 ~ 1.0938 | 1/2 |
1" x 82
deg HSS countersink (USA).
Piloted countersinks (10-24 thread) with 0.001"
increment
adjustment micro-stop cage adapters.
Sizes: #40 (3/32" pilot), #30 (1/8" pilot), #21
(5/32" pilot), #10 (3/16" pilot)
all 100 deg.
A 3/4" (19mm), five-flute reamer/countersink, handy for lathe work.
General Model #196.
5-1/8" (130mm) overall length.
Handy for deburring a rotating hole on a
lathe.
A
Table of Decimal Inch Equivalencies for Fractional, Numbered, Lettered &
Metric Drill Bits
Fract. (in) |
Decimal (in) |
Wire No. |
Metric (mm) |
Fract. (in) |
Decimal (in) |
Wire No. |
Metric (mm) |
Fract. (in) |
Decimal (in) |
Letter |
Metric (mm) |
||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0.0098 | 0.25 | 0.1065 | 36 | 0.3480 | S | ||||||||
0.0118 | 0.30 | 7/64 | 0.1094 | 0.3543 | 9.00 | ||||||||
0.0135 | 80 | 0.1100 | 35 | 0.3580 | T | ||||||||
0.0138 | 0.35 | 0.1102 | 2.80 | 23/64 | 0.3594 | ||||||||
0.0145 | 79 | 0.1110 | 34 | 0.3680 | U | ||||||||
1/64 | 0.0156 | 0.1130 | 33 | 0.3740 | 9.50 | ||||||||
0.0157 | 0.40 | 0.1142 | 2.90 | 3/8 | 0.3750 | ||||||||
0.0160 | 78 | 0.1160 | 32 | 0.3770 | V | ||||||||
0.0177 | 0.45 | 0.1181 | 3.00 | 0.3860 | W | ||||||||
0.0180 | 77 | 0.1200 | 31 | 25/64 | 0.3906 | ||||||||
0.0197 | 0.50 | 1/8 | 0.1250 | 0.3937 | 10.00 | ||||||||
0.0200 | 76 | 0.1285 | 30 | 0.3970 | X | ||||||||
0.0210 | 75 | 0.1360 | 29 | 0.4040 | Y | ||||||||
0.0217 | 0.55 | 0.1378 | 3.50 | 13/32 | 0.4063 | ||||||||
0.0225 | 74 | 0.1405 | 28 | 0.4130 | Z | ||||||||
0.0236 | 0.60 | 9/64 | 0.1406 | 0.4134 | 10.50 | ||||||||
0.0240 | 73 | 0.1440 | 27 | 27/64 | 0.4219 | ||||||||
0.0250 | 72 | 0.1470 | 26 | 0.4331 | 11.00 | ||||||||
0.0256 | 0.65 | 0.1495 | 25 | 7/16 | 0.4375 | ||||||||
0.0260 | 71 | 0.1520 | 24 | 0.4528 | 11.50 | ||||||||
0.0276 | 0.70 | 0.1540 | 23 | 29/64 | 0.4531 | ||||||||
0.0280 | 70 | 5/32 | 0.1563 | 15/32 | 0.4688 | ||||||||
0.0292 | 69 | 0.1570 | 22 | 0.4724 | 12.00 | ||||||||
0.0295 | 0.75 | 0.1575 | 4.00 | 31/64 | 0.4844 | ||||||||
0.0310 | 68 | 0.1590 | 21 | 0.4921 | 12.50 | ||||||||
1/32 | 0.0313 | 0.1610 | 20 | 1/2 | 0.5000 | ||||||||
0.0315 | 0.80 | 0.1660 | 19 | 0.5118 | 13.00 | ||||||||
0.0320 | 67 | 0.1695 | 18 | 33/64 | 0.5156 | ||||||||
0.0330 | 66 | 11/64 | 0.1719 | 17/32 | 0.5313 | ||||||||
0.0335 | 0.85 | 0.1730 | 17 | 0.5315 | 13.50 | ||||||||
0.0350 | 65 | 0.1770 | 16 | 35/64 | 0.5469 | ||||||||
0.0354 | 0.90 | 0.1772 | 4.50 | 0.5512 | 14.00 | ||||||||
0.0360 | 64 | 0.1800 | 15 | 9/16 | 0.5625 | ||||||||
0.0370 | 63 | 0.1820 | 14 | 0.5709 | 14.50 | ||||||||
0.0374 | 0.95 | 0.1850 | 13 | 37/64 | 0.5781 | ||||||||
0.0380 | 62 | 3/16 | 0.1875 | 0.5905 | 15.00 | ||||||||
0.0390 | 61 | 0.1890 | 12 | 19/32 | 0.5938 | ||||||||
0.0394 | 1.00 | 0.1910 | 11 | 39/64 | 0.6094 | ||||||||
0.0400 | 60 | 0.1935 | 10 | 0.6102 | 15.50 | ||||||||
0.0410 | 59 | 0.1960 | 9 | 5/8 | 0.6250 | ||||||||
0.0420 | 58 | 0.1968 | 5.00 | 0.6299 | 16.00 | ||||||||
0.0430 | 57 | 0.1990 | 8 | 41/64 | 0.6406 | ||||||||
0.0433 | 1.10 | 0.2010 | 7 | 0.6496 | 16.50 | ||||||||
0.0465 | 56 | 13/64 | 0.2031 | 21/32 | 0.6563 | ||||||||
3/64 | 0.0469 | 0.2040 | 6 | 0.6693 | 17.00 | ||||||||
0.0472 | 1.20 | 0.2055 | 5 | 43/64 | 0.6719 | ||||||||
0.0512 | 1.30 | 0.2090 | 4 | 11/16 | 0.6875 | ||||||||
0.0520 | 55 | 0.2130 | 3 | 0.6890 | 17.50 | ||||||||
0.0550 | 54 | 0.2165 | 5.50 | 45/64 | 0.7031 | ||||||||
0.0551 | 1.40 | 7/32 | 0.2188 | 0.7087 | 18.00 | ||||||||
0.0591 | 1.50 | 0.2210 | 2 | 23/32 | 0.7188 | ||||||||
0.0595 | 53 | 0.2280 | 1 | 0.7283 | 18.50 | ||||||||
1/16 | 0.0625 | 0.2340 | A | 47/64 | 0.7344 | ||||||||
0.0630 | 1.60 | 15/64 | 0.2344 | 0.7480 | 19.00 | ||||||||
0.0635 | 52 | 0.2362 | 6.00 | 3/4 | 0.7500 | ||||||||
0.0669 | 1.70 | 0.2380 | B | 49/64 | 0.7656 | ||||||||
0.0670 | 51 | 0.2420 | C | 0.7677 | 19.50 | ||||||||
0.0700 | 50 | 0.2460 | D | 25/32 | 0.7813 | ||||||||
0.0709 | 1.80 | 1/4 | 0.2500 | E | 0.7874 | 20.00 | |||||||
0.0730 | 49 | 0.2559 | 6.50 | 51/64 | 0.7969 | ||||||||
0.0748 | 1.90 | 0.2570 | F | 0.8071 | 20.50 | ||||||||
0.0760 | 48 | 0.2610 | G | 13/16 | 0.8125 | ||||||||
5/64 | 0.0781 | 17/64 | 0.2656 | 0.8268 | 21.00 | ||||||||
0.0785 | 47 | 0.2660 | H | 53/64 | 0.8281 | ||||||||
0.0787 | 2.00 | 0.2720 | I | 27/32 | 0.8438 | ||||||||
0.0810 | 46 | 0.2756 | 7.00 | 0.8465 | 21.50 | ||||||||
0.0820 | 45 | 0.2770 | J | 55/64 | 0.8594 | ||||||||
0.0827 | 2.10 | 0.2810 | K | 0.8661 | 22.00 | ||||||||
0.0860 | 44 | 9/32 | 0.2813 | 7/8 | 0.8750 | ||||||||
0.0866 | 2.20 | 0.2900 | L | 0.8858 | 22.50 | ||||||||
0.0890 | 43 | 0.2950 | M | 57/64 | 0.8906 | ||||||||
0.0906 | 2.30 | 0.2953 | 7.50 | 0.9055 | 23.00 | ||||||||
0.0935 | 42 | 19/64 | 0.2969 | 29/32 | 0.9063 | ||||||||
3/32 | 0.0938 | 0.3020 | N | 59/64 | 0.9219 | ||||||||
0.0945 | 2.40 | 5/16 | 0.3125 | 0.9252 | 23.50 | ||||||||
0.0960 | 41 | 0.3150 | 8.00 | 15/16 | 0.9375 | ||||||||
0.0980 | 40 | 0.3160 | O | 0.9449 | 24.00 | ||||||||
0.0984 | 2.50 | 0.3230 | P | 61/64 | 0.9531 | ||||||||
0.0995 | 39 | 21/64 | 0.3281 | 0.9646 | 24.50 | ||||||||
0.1015 | 38 | 0.3320 | Q | 31/32 | 0.9688 | ||||||||
0.1024 | 2.60 | 0.3346 | 8.50 | 0.9842 | 25.00 | ||||||||
0.1040 | 37 | 0.3390 | R | 63/64 | 0.9844 | ||||||||
0.1063 | 2.70 | 11/32 | 0.3438 | 1 | 1.0000 | 25.40 | |||||||
Fract. (in) |
Decimal (in) |
Wire No. |
Metric (mm) |
Fract. (in) |
Decimal (in) |
Letter |
Metric (mm) |
Fract. (in) |
Decimal (in) |
Letter |
Metric (mm) |
Reamers
Fractional
HSS reamer set
(import)
1/16"
to 1/2" by 1/64" in a
Huot index case.
See
reamer information.
A set of 14, over &
under sized
(+/-0.001")
decimal HSS chucking
reamers
(import).
These reamers are
+/-0.001" of the standard fractional
sizes: 1/8",
3/16",
1/4",
5/16",
3/8",
7/16",
1/2".
NOMINAL SIZE | PLUS 0.0010" | MINUS 0.0010" |
0.1250" | 0.1260" | 0.1240" |
0.1875" | 0.1885" | 0.1865" |
0.2500" | 0.2510" | 0.2490" |
0.3125" | 0.3135" | 0.3115" |
0.3750" | 0.3760" | 0.3740" |
0.4375" | 0.4385" | 0.4365" |
0.5000" | 0.5010" | 0.4990" |
Drilled holes are for clearance. Precision holes
are either
bored, reamed or ground. The hole should be ~1/64"
smaller than the reamer. Chamfer the hole
before reaming.
Liberally lubricate the reamer & hole
with the proper
cutting oil before starting. To
keep a tight tolerance, run
the reamer at the lowest RPM. When the reamer is all
the way through, stop rotation & then withdraw.
Running
a turning reamer in & out can increase the
hole size.
Chucking reamers have long
shafts that
allow some flexing to follow the hole.
Eleven, adjustable, precision
hand reamers
(India)
for holes from
15/32"
to
1-1/2"
or
.468'' to 1-1/2".
Adjusting the nuts
expands
the reamer to the
smallest size of the next larger sized
tool.
Setting to a precise size is tedious even with a
micrometer; reamed test holes,
recommended.
I clamp the shank's square end into the
bench vise & adjust using two, open-end
wrenches.
The two nuts move & press the six blades along &
against slants in the bottom
of the six grooves.
ADJUSTABLE REAMER SET SPECIFICATIONS | ||||
A | 1/2" | 15/32" ~ 17/32" | 0.468" ~ 0.530" | 11.88mm ~ 13.46mm |
B | 9/16" | 17/32" ~ 19/32" | 0.530" ~ 0.593" | 13.46mm ~ 15.06mm |
C | 5/8" | 19/32" ~ 21/35" | 0.593" ~ 0.655" | 15.06mm ~ 16.63mm |
D | 11/16" | 21/32" ~ 23/32" | 0.655" ~ 0.718" | 16.63mm ~ 18.23mm |
E | 3/4" | 23/32" ~ 25/32" | 0.718" ~ 0.780" | 18.23mm ~ 19.81mm |
F | 13/16" | 25/32" ~ 27/32" | 0.780" ~ 0.842" | 19.81mm ~ 21.39mm |
G | 7/8" | 27/32" ~ 15/16" | 0.842" ~ 0.937" | 21.39mm ~ 23.80mm |
H | 1" | 15/16" ~ 1-1/16" | 0.937" ~ 1.062" | 23.80mm ~ 26.98mm |
I | 1-1/8" | 1-1/16" ~ 1-3/16" | 1.062" ~ 1.187" | 26.98 mm~ 30.14mm |
J | 1-1/4" | 1-3/16" ~ 1-11/32" | 1.187" ~ 1.344" | 30.14mm ~ 34.13mm |
K | 1-7/16" | 1-11/32" ~ 1-1/2" | 1.344" ~ 1.500" | 34.13mm ~ 38.10mm |
Chuck capacity is 0.17" to 0.4".
This tap handle holds up to the
3/4" E
hand reamer
or 1/4" to 1/2" tap sizes.
Maximum chuck capacity is 0.502".
This larger tap handle
holds up
to the 1-1/16" H hand reamer.
Taper-pin Reamers
Tapered pins & tapered reamers.
Taper pins & their taper-pin reamers.
Sizes top to
bottom: #2, #1, #0, #3/0, & #4/0.
For short pins, drill the small diameter size.
For long pins, step drilling
may be required;
refer to tables in
Machinery's Handbook.
TAPER REAMER SIZES | ||
SIZE# |
DIAMETER SMALL END (in.) |
DIAMETER LARGE END (in.) |
4/0 | 0.0869 | 0.1142 |
3/0 | 0.1029 | 0.1302 |
0 | 0.1287 | 0.1638 |
1 | 0.1447 | 0.1798 |
2 | 0.1605 | 0.2008 |
Tapered hand reamer (USA).
Floating Reamer Holder
Floating
holders allow a chamber
reamer to self-align with the
barrel.
The floating
portion of the holder has a precision-
honed hole.
1/4"
& 1/2"
shanks use an adaptor bushing.
A
set screw secures the tool in the holder
(Clymer).
Shown are 22 short rough & finish reamers,
go & no-go gauges
plus MT2,
1/2"
&
3/8"
shanks.
COUNTERBORE SIZES | ||||
BOLT SIZE | COUNTERBORE SIZE (inches) | PILOT SIZE (inches) | ||
#6 | - | .2420 | - | .1500 |
#8 | 19/64 | .2968 | 11/64 |
|
#10 | 21/64 | .3281 | 13/64 | .2031 |
1/4" | 13/32 | .4062 | 9/32 | .2812 |
5/16" | 1/2 | .5000 | 11/32 | .3438 |
3/8" | 19/32 | .5938 | 13/32 | .4063 |
1/2" | 25/32 | .7813 | 17/32 | .5313 |
Metric counterbore set: M3,
M4, M5, M6, M8,
M10, & M12. The shanks are metric sizes, too.
The
#6, #8 & #10 counterbores use
interchangeable (3/32" shank) carbon-steel
pilots.
Different combinations allow for tighter or
looser fit for the bolt.
Pilot sizes: 1/8", 5/32",
3/16", 7/32", 1/4", 5/16". The 1" counterbore
has
1/2" & 9/16"
pilots with 3/16" shanks.
One of the pilots had a burr
that needed
to be removed via precision grinding.
A small set screw against a tapered flat holds
the pilot's
stem. Detail of a 5/16" pilot.
1" counterbore (USA) with
interchangeable pilots (import).
An example of three counterbores for a 10-32
cap-head bolt (left/center) for a
tooling plate.
Engraving Bits
Solid carbide engraving tools for the
CNC mill.
The end was first split in
half with a diamond-wheeled
surface grinder then the tip was diamond ground
to have relief behind the single-flute
cutting edge.
The
point was then relieved even more using a fine diamond file.
Factory sharpened half round carbide engraver bit.
Combo Drill-Tap Bits
HSS combination drill bit & tap.
Imperial sizes: 4-40, 6-32, 8-32,
10-32, 10-24,
1/4-28, 1/4-20, 5/16-18, 3/8-16 &
1/2-13.
HSS combination drill bit & tap.
Metric sizes: M3x.5, M4x.7, M5x.8, M6x1,
M8x1.25, & M10x1.5
Each bit has integral deburr/countersink & quick-change hex shaft.
The taper after the threading prevents over drilling.
Imperial sizes: 6-32, 8-32,
10-24, 10-32, 12-24 & 1/4-20.
Drill/tap multiple
10-24
threads; lubricate, first.
I disconnected the
RF-25
fine down feed & used
the spring-loaded quill
arm. Mill set at 110 RPM.
After drilling the hole the tap pulled the
quill down.
Diamond Wheels
Assortment of 50, 1/8" shank diamond wheels.
Set of 20, 1/8" shank, diamond pin
grinders. See
Tool Post Grinder.
Wood Bits
Bits for wood & masonry shown for comparative purposes.
Brad-point wood bits (GER) in metric (4, 5, 6, 7, 8, 10 &
12mm) &
imperial (1/8, 3/16, 1/4, 5/16, 3/8, 7/16 & 1/2").
A brad point helps to reduce bit wander
as the hole is drilled.
Only use in wood.
A set of Forstner-style wood
bits (import) that drill
very clean, dimensionally accurate, flat-bottomed holes.
Whenever possible, use a drill press at low RPM,
depth stop & clamp the piece;
all of which combine to
produce an accurate hole.
Sizes: 1/4" to 2-1/8" by 1/8".
On a project, I was
making 5/8" holes for standard
sized wooden dowels but they were a loose fit.
So,
I put a 5/8" Forstner bit into the lathe, matched
its
small angle on the
compound & removed a small
amount, off the side.
Because of this bit's design,
the mod did not change its cutting
characteristics.
Bought a single, 5/8" bit to restore the set.
Instead of cutting the bit down, I would now use
the
tool post grinder set at the matching angle.
Wood Speedbors (TM).
Sizes:
1/2",
5/8", 3/4", 7/8", 1",1-1/4".
Spade-type, wood drill bits with hexagonal shanks.
Masonry Bits
Milwaukee
Brand masonry bits (USA) with brazed
carbide tips. Work best with a hammer drill.
Sizes: 3/16"x3", 1/4"x4", 5/16"x4", 3/8"x4",
1/4"x6", 1/2"x6".
Drill Bits,
Left-hand
Drill Bits,
Long Boy,
Silver & Deming,
Metric,
Tapered Shank,
Drill Bit
Gauges,
Sharpeners,
Center Drill Bits,
Stepped Drill Bits,
Circle Cutter,
Countersinks,
Reamers,
Floating Reamer Holder,
Taper-pin Reamers,
Counterbores,
Engraving Bits,
Combo Drill-Tap Bits,
Diamond Wheels,
Wood bits,
Masonry Bits