b'DRILL SURFACE TREATMENTS COMMON TAPPING TERMSBlack OxideTiN CoatingBlack oxide is the most basic surface treatmentTitanium Nitride (TiN) performance coating can increase tool life recommended for drilling in iron and steel. It is notand productivity by allowing higher speeds and heavier feeds. It recommended for drilling in aluminum, magnesiumis an excellent general purpose coating for protecting tools from wear. TiN coating is an excellent choice for drilling in iron and or similar materials.steel. It is also recommended for drilling in aluminum, magnesiumChamfer Styles in Standard TapsDrilling with a black oxide treated drill provides: or similar materials.Increased tempering and stress relieving Drilling with a TiN coated drill provides: Reduced galling and chip welding Increased surface hardnessDrilling Operating Parameters ReducedcoefficientoffrictionIncreased retention of lubricants Increased corrosion resistanceA thermal barrierAdditional tempering and stress relievingTable of Cutting SpeedsFractional SizesSurface Feet per Minute10\' 12\' 15\' 20\' 25\' 30\' 35\' 40\' 45\' 50\' 60\' 70\' 80\' 90\' 100\' End ViewsDiameter Revolutions per MinuteSize1/64 2445 2934 3667 4889 6112 7334 8556 9778 11001 12223 14668 17112 19557 22001 244461/32 1222 1467 1833 2445 3056 3667 4278 4889 5500 6112 7334 8556 9778 11001 122233/64 815 978 1222 1630 2037 2445 2852 3259 3667 4074 4889 5704 6519 7334 81491/16 611 733 917 1222 1528 1833 2139 2445 2750 3056 3667 4278 4889 5500 61125/64 489 587 733 978 1222 1467 1711 1956 2200 2445 2934 3422 3911 4400 48893/32 407 489 611 815 1019 1222 1426 1630 1833 2037 2445 2852 3259 3667 40747/64 349 419 524 698 873 1048 1222 1397 1572 1746 2095 2445 2794 3143 34921/8 306 367 458 611 764 917 1070 1222 1375 1528 1833 2139 2445 2750 3056 Angle of Thread Pitch9/64 272 326 407 543 679 815 951 1086 1222 1358 1630 1901 2173 2445 2716 TheangleincludedbetweentheflanksofthethreadmeasuredinThe distance from any point on a screw or tap thread to a correspond-5/32 244 293 367 489 611 733 856 978 1100 1222 1467 1711 1956 Drilling Operating Parameters ing point on the next thread, measured parallel to the axis. The pitch 2200 2445 an axial plane11/64 222 267 333 444 556 667 778 889 1000 1111 1333 1556 1778 2000 22223/16 204 244 306 407 509 611 713 815 917 1019 1222 1426 1630 1833 2037 Back Taper equals one divided by the number of threads per inch13/64 188 226 282 376 470 564 658 752 846 940 1128 1316 1504 1692 1880 A slight axial relief on the thread of the tap which makes the pitchPitch Diameter7/32 175 210 262 349 437 524 611 698 786 873 1048 1222 1397 1572 1746 diameter of the thread near the shank somewhat smaller than that On a straight thread, the diameter of any imaginary coaxial15/64 163 196 244 326 407 489 570 652 733 815 978 1141 1304 1467 16301/4 153 183 229 306 382 458 535 611 688 764 917 1070 1222 1375 1528 of the chamfered end cylinder, the surface of which would pass through the threadSpeeds for High-Speed Steel Drills9/32 136 163 204 272 340 407 475 543 611 679 815 951 1086 1222 1358 Bottoming Chamferprofileatsuchpointsastomakeequalthewidthofthethreads 5/16 122 147 183 244 306 367 428 489 Material 611 733 856 SFM 1100 1222 SFM The shortest chamfer (1-2 threads long) for threading close to theand the width of the spaces cut by the surface of the cylinder550 978 Material11/32 111 133 167 222 278 333 389 444 500 556 667 778 889 1000 1111Aluminum and its Alloys 200300 Steel (Continued) bottom of blind holes3/8 102 122 153 204 255 306 357 407 458 509 611 713 815 917 1019Brass and Bronze (Ordinary) 150300 Steel (.4 carbon to .5 carbon) 708013/32 94 113 141 188 235 282 329 376 423 470 564 658 752 846 940 Chamfer On a taper thread, the diameter at a given distance from aBronze (High Tensile) 70150 Tool (1.2 carbon) 50607/16 87 105 131 175 218 262 306 349 393 437 524 611 698 786 873 The tapering of the threads at the front end of each land of a tap, byreference plane perpendicular to the axis of an imaginary Die Castings (Zinc Base)300400 Forgings 405015/32 81 98 122 163 204 244 285 326 367 407 489 570 652 733 815 cuttingawayandrelievingthecrestofthefirstfewteeth,todistribute co-axial cone, the surface of which would pass through the1/2 76 92 115 153 191 229 267 306 Iron 382 458 535 611 688 764 2030344 Alloy300 to 400 BrinellCast (Soft) 100150 High Tensile (Heat Treated) the cutting action over several teeththreadprofileatsuchpointsastomakeequalthewidthof9/16 68 81 102 136 170 204 238 272 306 340 407 475 543 611 6795/8 61 73 92 122 153 183 214 244 Cast (Medium hard) 428 70100 550 611 3040 Chamfer Relief the threads and the width of the spaces cut by the surface 275 306 367 489 35 to 40 Rockwell C11/16 56 67 83 111 139 167 194 222 250 278 333 389 3040 500 556 2535 The gradual decrease in land height from cutting edge to heel on theof the coneHard Chilled 444 40 to 45 Rockwell C3/4 51 61 76 102 127 153 178 204 229 255 306 357 407 458 509Malleable 8090 45 to 50 Rockwell C 1525 chamfered portion, to provide clearance for the cutting action as thePlug Chamfer13/16 47 56 71 94 118 141 165 188 Magnesium and its Alloys 329 250400 423 470 715212 235 282 376 50 to 55 Rockwell C tap advances The most common chamfer (3-5 threads long), for hand or machine7/8 44 52 65 87 109 131 153 175 196 218 262 306 349 393 437Monel Metal or High-Nickel Steel 3050 Stainless Steel81 102 122 143 163 183 204 244 285 326 367 407 Chordal Hook Angle tapping in through or blind holes15/16 41 49 61 Drilling Operating Parameters 3080 The angle between the chord passing through the root and crest of RakePlastics or Similar Materials (Bakelite) 100300 Free Machining Grades1 38 46 57 76 95 115 134 153 172 191 229 267 306 344 382Work Hardening Grades15501-1/8 34 41 51 68 85 102 119 136 Steel 170 204 238 272 306 340153 244 Wood 306 300400a thread form at the cutting face, and a radial line through the crestAny deviation of a straight cutting face of the tooth from a radial line.1-1/4 31 37 46 61 76 92 107 122 138 153 183 214 80110 275Mild (.2 carbon to .3 carbon)1-3/8 28 33 42 56 69 83 97 111 125 139 167 194 222 250 278 at the cutting edge Positive Rake means that the crest of the cutting face is angularly 1-1/2 25 31 38 51 64 76 89 102 115 127 153 178 204 229 255 Crest advanced ahead of the balance of the face of the tooth. Negative Thetopsurfacejoiningthetwoflanksofathread.Thecrestofan Rake means that the same point is angularly behind the balance of Speeds for High-Speed Steel Drills Feed Per Drill Revolution external thread is at its major diameter, while the crest of an internalthe cutting face of the tooth. Zero Rake means that the cutting face is Material SFM Material SFM Drill Dia. Range Light Medium Heavy thread is at its minor diameter directly on the center lineAluminum and its Alloys 200300 Steel (Continued) 1/16 to 1/8" .0005.0010 .0010.0020 .0020.0040 Cutting Face Spiral Point (Chip Driver)Brass and Bronze (Ordinary) 150300 Steel (.4 carbon to .5 carbon) 7080 1/8 to 1/4" .0010.0030 .0030.0050 .0040.0060 The leading side of the land in the direction of rotation for cutting onAsupplementaryangularflutingcutinthecuttingfaceofthelandattheBronze (High Tensile) 70150 Tool (1.2 carbon) 5060 1/4 to 3/8" .0030.0050 .0050.0070 .0060.0100 which the chip impinges chamfer end. It is slightly longer than the chamfer on the tap, and of Die Castings (Zinc Base)300400 Forgings 4050 3/8 to 1/2" .0040.0060 .0050.0080 .0080.0120 Flutes the opposite hand to that of rotationIron Alloy300 to 400 Brinell 2030 1/2 to 3/4" .0050.0070 .0070.0100 .0090.0140 The longitudinal channels formed in a tap to create cutting edgesTaper ChamferCast (Soft) 100150 High Tensile (Heat Treated) 3/4 to 1" .0070.0100 .0090.0140 .0140.0200 onthethreadprofile,andtoprovidechipspacesandcuttingfluid A long chamfer (8-10 threads long) for easier starting and engagement Cast (Medium hard) 70100 35 to 40 Rockwell C 3040 passages in the work piece. More working teeth means that less tapping torque is Hard Chilled 3040 40 to 45 Rockwell C 2535 Height of Thread required, and the chip load is reduced on each toothMalleable 8090 45 to 50 Rockwell C 1525 Speeds and Feeds for Deep-Hole Drilling The distance between the crest and the base of a thread measuredThreads Per InchGENERAL TOOLINFORMATIONMagnesium and its Alloys 250400 50 to 55 Rockwell C 715 Holes which must be drilled three diameters deep or more fall into the deep-hole normal to the axis The number of threads in one inch of lengthMonel Metal or High-Nickel Steel 3050 Stainless Steel drilling class, and some adjustment of feeds and speeds is necessary. The deeper the Lead INFORMATION GENERAL TOOL Plastics or Similar Materials (Bakelite) 100300 Free Machining Grades 3080 hole, the greater the tendency there is for chips to pack and clog the flutes of the drill. The distance a screw thread advances axially in one complete turn. Steel Work Hardening Grades1550 This increases the amount of heat generated and prevents the coolant from conducting On a single lead screw or tap, the lead and pitch are identical. OnMild (.2 carbon to .3 carbon) 80110 Wood 300400the heat away from the point. A build-up of heat at the point will eventually result in a double-lead screw or tap, the lead is twice the pitch, etc.premature failure. Step drilling, also called peck drilling, is the practice of drilling a short distance,then withdrawing the drill. This often reduces chip packing. The deeper the hole, theFeed Per Drill Revolution more frequent the drill must be retracted to be effective. Generally, a reduction inspeed and feed to reduce the amount of heat generated is required in most deep-holeDrill Dia. Range Light Medium Heavy800-942-1501 www.triumphtwistdrill.comwww.triumphtwistdrill.com800-942-1501applications, where coolant cannot be effectively applied.62 1/16 to 1/8" .0005.0010 .0010.0020 .0020.0040 631/8 to 1/4" .0010.0030 .0030.0050 .0040.00601/4 to 3/8" .0030.0050 .0050.0070 .0060.0100 Speed and Feed Reduction(Based upon hole depth)3/8 to 1/2" .0040.0060 .0050.0080 .0080.0120Hole Depth to Dia. Ratio SpeedFeed 1/2 to 3/4" .0050.0070 .0070.0100 .0090.0140 (times drill diameter) Reduction Reduction3/4 to 1" .0070.0100 .0090.0140 .0140.0200 3 10% 10%4 20% 10%5 30% 20%Speeds and Feeds for Deep-Hole Drilling 6 3540% 20%Note: Remember that these values are only a starting point. They may require adjustment basedHoles which must be drilled three diameters deep or more fall into the deep-hole on conditions or individual requirements.drilling class, and some adjustment of feeds and speeds is necessary. The deeper thehole, the greater the tendency there is for chips to pack and clog the flutes of the drill.This increases the amount of heat generated and prevents the coolant from conductingthe heat away from the point. A build-up of heat at the point will eventually result inpremature failure. Step drilling, also called peck drilling, is the practice of drilling a short distance,then withdrawing the drill. This often reduces chip packing. The deeper the hole, themore frequent the drill must be retracted to be effective. Generally, a reduction inspeed and feed to reduce the amount of heat generated is required in most deep-holeapplications, where coolant cannot be effectively applied.Speed and Feed Reduction(Based upon hole depth)Hole Depth to Dia. Ratio SpeedFeed (times drill diameter) Reduction Reduction3 10% 10%4 20% 10%5 30% 20%6 3540% 20%Note: Remember that these values are only a starting point. They may require adjustment basedon conditions or individual requirements.'