Drills Reamers Taps User Guide
Contents
1. 0 7854 4 C 2 r 6 2832 3 14164 6 2832 3 1416 0 564 gt d C 3 1416 0 7854 1 128 REGULAR HEXAGON area R radius of circumscribed circle radius of inscribed circle A 2 5988 2 598R 3 464 R S 1 155 0 8665 0 866R The construction of a regular hexagon forms six equilateral triangles thus the area of the hexagon can also be found by calculating the area of the equilateral triangle and multiplying the result by six Brooke 93 Cutting Tools Limited USEFUL FORMULAE rpm Surface Speed metres min S Dia mm X Surface Speed metres min 4000 Feed rate mm min Feed Rate mm rev rpm Penetration rate mm min rpm X feed rate mm rev 94 Brooke Cutting Tools Limited USEFUL TAPERS Cutting Tools Limited Cone of Included Angle Angle with Centre Line 1in2 28 4 200 14 2 107 2 1 2 22 37 120 117 18 360 1in3 18 55 280 9 27 440 3 1 2 16 15 380 8 T 491 1in4 14 15 00 7 T 300 4 1 2 12 40 500 6 20 250 1in5 11 25 160 5 42 380 5 1 2 10 23 200 5 11 400 1in6 9 31 360 4 45 481 6 1 2 8 47 520 4 23 560 1in7 8 10 160 4 5 80 7 1 2 7 37 430 3 48 520 1in8 7 9 107 32 34 356 8 1 2 6 43 580 3 21 590 1in9 6 21 340 3 10 470 9 1 2 6 1 320 3 0 460 1in12. 1 micron 1 1000mm DIAMETER OR WIDTH 3to 6to 10 to 18 to 30 to 50 to 80 to 6mm 10mm 18mm 30mm 50mm 80mm 120mm Tol 3mm Brooke 99 Cutting Tools Limited 1 10 01 4 CUTTING TOOLS Quality and Service to Industries Worldwide ISO 9002 Brooke Cutting Tools Princess Street Sheffield S4 7UU Tel 44 0 114 261 7200 Fax 44 0 114 261 7370 Email info castlebrooke co uk Website www castlebrooke co uk Brooke Cutting Tools Limited
3. g h 84 Possible Cause Using the incorrect tap Solution Use the recommended tap See page 55 58 Possible Cause The tap is too dull Solution Use a tap which is in good condition Possible Cause The drilled hole is too small Solution Use the recommended tapping drill size See page 59 64 Possible Cause The drilled hole is too shallow Solution Allow clearance at the bottom of the hole when drilling Possible Cause Mis alignment of the tap and the hole Solution Care must be taken to align the tap with the hole before starting totap Possible Cause The flutes are clogged with chips Solution Use a spiral point or spiral flute tap Possible Cause Excessive tapping speed is applied Solution Use the recommended tapping speed See page 66 71 Possible Cause The tap holding device is not suitable Solution Use the appropriate tapping attachment Possible Cause The work material is work hardened Solution Use serial taps Possible Cause Lack of or the wrong type of lubricant Brooke Cutting Tools Limited Lack of or the wrong type of lubricant Solution Apply an adequate supply and the correct type of lubricant to the chamfer lead ofthe tap Possible Cause Incorrect rake angle Solution Use the recommended tap for the material See page 55 58 Brooke 85 Cutting Tools Limited GENERAL INFORMATION INCH MILLIMETER CONVERSION TABLE 0 1 2
4. 61 BSF Nominal Tapping Diameter TPI Drill Size mm 3 8 20 8 3 7 16 18 9 8 1 2 16 11 9 16 16 12 7 5 8 14 14 3 4 12 16 5 7 8 11 19 5 1 10 22 5 1 1 8 9 25 5 1 1 4 9 29 1 1 2 8 34 5 UNC No 3 48 2 No 4 40 2 25 No 5 40 2 6 No 6 32 2 75 No 8 32 34 No 10 24 3 8 No 12 24 44 1 4 20 5 1 56 18 6 6 3 8 16 8 7 16 14 9 4 1 2 13 10 8 9 16 12 12 2 5 8 11 13 5 3 4 10 16 5 7 8 9 19 5 1 8 22 1 1 8 7 25 1 1 4 7 28 1 3 8 6 31 1 1 2 6 34 1 3 4 5 39 2 4 1 2 45 62 Brooke Cutting Tools Limited UNF Nominal Diameter No 3 No 4 No 5 No 6 No 8 No 10 No 12 3 16 1 4 5 16 3 8 7 16 1 2 9 16 5 8 3 4 7 8 1 1 1 8 1 1 4 1 3 8 1 1 2 gt 5 48 44 36 32 32 28 24 20 18 18 14 12 12 12 12 254 28 2 31 3 34 8 38 3 43 1 47 9 52 9 59 1 65 1 72 6 Brooke Cutting Tools Limited Tapping Drill Size mm 21 2 35 2 65 2 9 3 5 4 1 4 6 4 5 5 6 9 85 9 8 41 5 12 8 14 5 17 5 20 5 23 5 26 5 29 5 32 5 36 5 1 3 9 34 2 65 2 3 2 05 1 8 1 55 1 4 63 BSP Nominal Diameter 1 8 1 4 3 8 1 2 5 8 3 4 7 8 1 1 1 4 1 1 2 1 3 4 2 BSPT 1 8 1 4 3 8 1 2 3 4 1 1 1 4 1 1 2 7 NPS 1 8 1 4 3 8 12 3 4 1 1 1 4 1 1 2 2 64 19 19 14 14 11 11 11 11 28 19 19 14 11 11 11 27 18 18 14 11 1 2 11 1 2 11 1 2 11 1 2 Brooke Cutting Tools Limited Tappin
5. n MAX 2m3 14 5 2 MINIMUM G GRADES MIN BASIC GRADES PITCH DIAMETER Unified Threads NUTS 1B MAX 2B MAX 3B MAX o 0 lt 211 2 lt o 1 MINIMUM ALL NUT CLASSES BASIC PITCH DIAMETER Brooke Cutting Tools Limited 77 Class 1 Tap This is closest to basic having little oversize allowance and is normally specified for close fit threads eg Unified 3B Metric 4H 5H Class 2 Tap This is normally specified for medium fit threads eg Unified 2B Metric 6H 4G 5G Class 3 Tap This is futhermost above basic size and used for free fit threads eg Unified 1B Metric 7H 8H 6G Under favourable working conditions the following thread tolerances should be produced by the new class taps Class 1 Class 2 Class 3 Metric 4H 5H 6H 4G 5G 7H 8H 6G Unified 3B 2B 1B Whitworth Form Close Class Medium Class Free Class BA Close Class Medium Class Free Class All Brooke HSS taps are supplied to Class 2 6H unless otherwise specified RE SHARPENING Maximum productivity and tap life can only be obtained from a tap that is kept in good condition and handled with care When re sharpening becomes necessary regrinding by hand is not recommended though it is probably better than using chipped or worn taps The recommended method is to use special tap grinding attachments or machines and to follow the original form of the
6. A short robust drill suited to portable drill applications Reduced Shank Drills General drilling for use in hand power tools MTS Drills General purpose drilling MTS Drills HSS Co General purpose drilling in difficult materials 10 Brooke Cutting Tools Limited Drills for specific applications More efficient drilling can be achieved by using a drill designed for a specific application The following drills are available ex stock from Brooke Drills for Roof Cladding Roof clad drilling Double Ended Body Drills Self centring drill designed to produce accurate holes in thin materials Cobalt Straight Shank Heavy Duty Jobber Drills HSS Co Drilling high tensile steels and other difficult materials TiN Coated Jobber Drills m For drilling in a production environment where higher speeds and or feeds are required Extra Length Drills Extra deep hole drilling Details on page 22 ADZe Cobalt Long Series Drills Long Chip HSS Co 555 55 ___ _ Parabolic Flute Form and Heavy Duty for general purpose long reach drilling Brooke 11 Cutting Tools Limited DH Cobalt Extra Length Drills HSS Co 05 Parabolic Flute Form and Heavy Duty for extra deep hole drilling ADZe Cobalt Jobber Drills Long Chip HSS Co Parabolic Flute Form and Heavy Duty for use on NC and CNC machines where high productivity and accurate holes are required ADZe Cobalt Stub Drills Long Chip
7. Metres Min 4 6 8 9 10 12 Tap Ses Revolutions mm Inch 1 6 1 16 800 1194 1592 1791 1988 2386 1 8 708 1065 1415 1598 1768 2121 2 637 955 1274 1433 1591 1909 22 3 32 579 869 1158 1303 1446 1736 2 5 510 764 1019 1147 1274 1527 3 1 8 425 637 849 955 1061 1273 3 5 364 546 728 819 909 1091 4 5 32 318 478 637 718 796 955 4 5 283 425 566 637 707 849 5 3 16 255 382 510 573 637 764 6 1 4 212 319 425 477 530 636 7 9 32 182 273 364 409 455 546 8 5 16 159 239 319 358 398 477 9 142 212 283 318 354 425 10 3 8 127 191 255 286 318 382 11 116 174 232 260 289 347 12 1 2 106 159 212 238 265 318 13 98 147 196 220 245 294 14 9 16 91 136 182 205 277 273 16 5 8 80 119 159 179 199 239 18 71 106 141 159 177 212 20 3 4 64 96 127 143 159 191 22 7 8 58 87 116 130 145 174 24 1 53 80 106 119 133 159 27 47 71 94 106 118 141 30 1 1 8 43 64 85 95 106 127 33 1 1 4 39 58 77 87 96 116 36 35 53 71 80 88 106 39 1 1 2 33 49 65 73 82 98 42 30 46 61 68 76 91 45 1 3 4 28 42 57 64 71 85 48 27 40 53 60 66 80 52 24 37 49 55 61 73 56 2 23 34 46 51 57 68 72 Brooke Cutting Tools Limited TO rpm CONVERSION CHART Cutting Tools Limited 15 18 21 25 27 30 36 per Minute 2983 3579 4176 4971 5369 5965 7158 2652 3182 3712 4419 4773 5303 6364 2386 2863 3341 3977 4295 4773 5727 2169 2603 3037 3616 3905 4339 5207 1909 2291 2673 3182 3436 3818
8. mm mm mm ue ul 25 400 50 800 164 0 397 25 797 51 197 132 0794 26 194 51 594 3 64 14191 26 591 51 991 116 1588 26 988 52 388 5 64 1 984 27 384 52 784 3 33 2381 27 781 53 181 764 2778 28 178 53 578 18 5 2 v v SATS 28 575 53 975 9 64 3572 28 972 54 372 5 32 3 969 29 369 54 769 11 68 4366 29 766 56 166 3 16 4762 30 162 55 562 13 64 5 159 30 599 55 959 732 5 556 30 956 56 356 15 64 5953 31 353 56 753 14 6350 31 750 57 150 17 64 6 747 32 147 57 547 9 32 7 144 32 544 57 944 19 64 7 541 32 941 58 341 516 7 938 33 338 58 738 21 60 8334 33 734 59 134 11 32 8 731 34 131 59 531 23 64 9 128 34 528 59 928 3 8 9 525 34 925 60 325 2564 9 922 35 322 60 722 13 32 10319 35 719 61 119 27164 10716 36 116 61 516 716 11 112 36 512 61 912 29 64 11 509 36 909 62 309 15 32 11 906 37 306 62 706 31 64 12 303 37 703 63 103 86 Brooke Cutting Tools Limited 3 mm 76 200 76 597 76 994 77 391 77 788 78 184 78 581 78 978 79 375 79 772 80 169 80 566 80 962 81 359 81 756 82 153 82 550 82 947 83 344 83 741 84 138 84 534 84 931 85 328 85 725 86 122 86 519 86 916 87 312 87 709 88 106 88 503 INCH MILLIMETER CONVERSION TABLE cont 1 2 33 64 17132 35 64 9 16 37 64 19 32 39
9. 4582 1591 1909 2227 2651 2864 3182 3818 1364 1636 1909 2273 2455 2727 3273 1193 1432 1671 1989 2148 2387 2864 1061 1273 1485 1768 1909 2122 2546 955 1146 1337 1591 1719 1909 2292 795 954 1113 1326 1432 1592 1909 682 818 955 1136 1227 1364 1636 597 716 835 994 1074 1193 1432 531 637 742 885 955 1061 1293 477 573 668 795 859 955 1146 434 521 608 723 781 868 1041 398 477 557 663 716 796 955 367 441 514 612 661 734 881 341 409 477 568 614 682 818 298 358 418 497 537 597 716 265 318 371 442 477 530 636 239 286 334 398 430 477 573 217 260 304 362 391 434 521 199 239 275 331 353 398 477 177 212 245 295 318 354 424 159 191 223 265 286 318 382 145 174 203 241 360 289 347 133 159 186 221 239 265 318 122 147 171 204 220 245 294 114 186 159 189 205 227 273 106 127 149 177 191 212 255 99 119 139 166 179 199 239 92 110 129 153 165 184 220 85 102 119 142 153 170 205 Brooke 73 CORRECT USE OF TAPS A guide to successful machine tapping Use the correct tap to suitthe application see page 55 58 Select the correct tapping drill size see page 59 65 Direct an adequate supply of the recommended lubricant to the cutting area of the tap see page 67 Make sure the workpiece is securely held Use a tapping attachment suited to the application and align the tap with the hole When using a machine without lead screw feed hand feed the tap until sufficient engagement produces self feed When using a machine with lead screw feed
10. HSS Co Parabolic Flute Form and Heavy Duty for use on NC and CNC machines where high productivity and accurate holes are required ADZe Cobalt Jobber Drills Short Chip HSS Co Parabolic Flute Form and Heavy Duty for use on NC and CNC machines where high productivity and accurate holes are required ADZe Cobalt Jobber Drills Cast Iron HSS Co Parabolic Flute Form and Heavy Duty for use on NC and CNC machines where high productivity and accurate holes are required MTS Extra Length Drill Extra deep hole drilling Details on page 22 amp 23 MTS Core Drills For enlarging diameters of existing holes whether drilled punched or cored Details on page 25 12 Brooke Cutting Tools Limited Recommended Speeds for Deep Holes Depth of Hole Speed Reduction 3 X Drill Diameter 1096 4 X Drill Diameter 20 5 x Drill Diameter 30 More than 6 X Drill Diameter 40 Recommended Feeds for Deep Holes Depth of Hole Feed Reduction 3 to 4 X Drill Diameter 10 5 to 8 X Drill Diameter 20 Extra Length Deep Hole Drills ADZe Long Chip The BROOKE Deep Hole drill has a specially shaped flute form commonly known as Parabolic which gives rigidity for deep hole drilling and improves chip flow enabling the full depth of the hole to be drilled without withdrawal These drills are of special robust design for use on tougher materials such as steels and cast irons with hardness up to 10
11. SQ IN FREE CUTTING 150 33 500 CARBON 0 3 to 0 4 Carbon 170 38 570 STEEL 0 3 to 0 4 Carbon 248 54 800 0 4 to 0 7 Carbon 206 44 650 0 4 to 0 7 Carbon 286 63 950 248 54 810 ALLOY STEEL Tough 330 74 1100 Hard 380 82 1250 Martensitic Free Cutting Martensitic 239 9f 810 STAINLESS Std Grade STEEL Austenitic Free Cutting Austenitic As Supplied Std Grade NIMONIC Wrought 300 67 1000 ALLOYS Cast 350 78 1170 Titanium Comm Pure 170 38 570 Titanium Comm Pure 200 43 650 Titanium Comm Pure 275 65 975 TITANIUM Titanium Alloyed 340 76 1140 Titanium Alloyed 380 85 1275 HSS Standard Grades 225 48 720 TOOL STEEL HSS Cobalt Grades Hot Working Steel 225 54 810 Cold Working Steel MANGANESE STEEL As Supplied 66 Brooke Cutting Tools Limited TECHNICAL DATA cont RECOMMENDED ALTERNATIVE TAP TYPE TAP TYPE TAP PERIPHERAL THROUGH BLIND THROUGH BLIND SPEED LUBRICANTS HOLE HOLE HOLE HOLE m min 10 15 Sp Point Sp Flute StrFlute Str Flute Sulphur based oil 8 10 Sp Point Sp Flute Str Flute Str Flute 8 12 Sulphur based oil Heavy duty Sp Point Sp Flute Str Flute Str Flute 2 6 Sulphur based oil See CAT Tap section pages 70 amp 71 2 4 57 oi Chlorinated See CAT Tap section pages 70 amp 71 2 4 il oi Sp Point Sp Flute Str Flute Str Flute 8 10 Sulphur based oil Sp Point Str Flute Str Flute 15 20 Sulphur based oil Th
12. 1 20 8 12 Above 20 6 10 Brooke Cutting Tools Limited 29 DRILLING PROBLEMS CAUSES AND SOLUTIONS Broken or Twisted Tangs a Possible Cause Bad fit between the drill sleeve and the shank of the drill Solution i Use only sleeves which are in good condition avoid worn or damaged sleeves ii Ensure the drill shank and sleeve are thoroughly clean Note The tang is not intended to transmit the drive it is only used for ejection The Morse Taper is self holding and relies on a good fit in the sleeve to transmit the drive Drill Web Split a Possible Cause The feed is too great Solution Use the correct feed for the drill size material see page 19 Possible Cause Insufficient lip clearance behind the cutting edge Solution Check that the lip clearance is as per information on page 28 29 c Possible Cause Excessive web thinning Solution The web thickness should not be less than 10 of the drill diameter Possible Cause Using a hard objectto seatthe drill in the sleeve Solution Use soft material e g copper or wood to seat the drill b d Worn outer Corners a Possible Cause The peripheral speed is too high for the material being drilled Solution Use the recommended speed see page 15 30 Brooke Cutting Tools Limited Broken outer Corners a Possible Cause Drilling thin material particularly when not properly supported Solution Use
13. 64 5 8 41 64 21 32 43 64 11 16 45 64 23 32 47 64 3 4 49 64 25 82 51 64 13 16 53 64 27 32 55 64 7 8 57 64 29 32 59 64 15 16 61 64 31 32 63 64 0 1 mm mm 12 700 38 100 13 097 38 497 13 494 38 894 13 891 39 291 14 288 39 688 14 684 40 084 15 081 40 481 15 748 40 878 15 875 41 275 16 271 41 671 16 668 42 068 17 066 42 466 17 462 42 862 17 859 43 859 18 256 43 656 18 653 44 053 19 050 44 450 19 447 44 847 19 844 45 244 20 241 45 641 20 638 46 038 21 034 46 434 21 431 46 831 21 828 47 228 22 225 47 625 22 622 48 022 23 019 48 019 23 416 48 816 23 812 49 212 24 209 49 609 24 606 50 006 25 003 50 403 Brooke Cutting Tools Limited 2 mm 63 500 63 897 64 294 64 691 65 088 65 484 65 881 66 278 66 675 67 071 67 468 67 866 68 262 68 859 69 056 69 453 69 850 70 247 70 644 71 041 71 438 71 834 72 231 72 628 73 025 73 422 73 019 74 216 74 612 75 009 75 406 75 803 3 mm 89 900 89 297 89 694 90 091 90 488 90 884 91 281 91 678 92 075 92 471 92 868 92 266 93 662 94 859 94 456 94 853 95 250 95 647 96 044 96 441 96 838 97 234 97 631 98 028 98 425 98 282 99 019 99 616 100 012 100 409 100 806 101 203 87 APPROXIMATE HARDNESS AND TENSILE STRENGTH CONVERSIONS TENSILE STRENGTH HRB HRC HV HB Tons MPa or inch N mm 50 95 90 21 320 55 100 100 23 350 60 110 105 25 390
14. 65 120 110 27 420 70 130 120 29 150 75 140 130 31 180 80 150 140 34 520 85 165 160 37 570 90 185 175 40 620 95 205 195 45 690 100 20 230 220 50 770 22 240 230 58 820 24 255 240 56 860 26 265 250 59 910 28 280 265 62 960 30 295 280 65 1000 32 310 290 68 1050 34 325 310 72 1110 36 345 325 75 1150 38 360 345 78 1200 40 380 365 83 1280 42 405 385 88 1360 44 425 405 92 1420 46 450 430 96 1480 48 480 455 102 1540 50 505 480 108 1670 52 545 112 1720 54 580 117 1800 56 615 122 1890 58 655 130 2000 60 695 135 2100 64 790 150 2320 66 855 163 2510 68 940 179 2770 70 1075 197 3030 75 1480 80 1865 HRB Hardness Rockwell B HRC Hardness Rockwell C HV Hardness Vickers Also DPN VPN DPH VPH HB Hardness Brinell Also BHN Note These values should be treated as approximate only and are suitable for calculating speeds and feeds or for general information purposes Do not use for treated high speed steel 88 Brooke Cutting Tools Limited HARDNESS CONVERSION CHART FOR HIGH SPEED STEEL HV30 HRC HV30 HRC 736 59 3 4 856 64 1 2 741 60 862 63 3 4 746 60 1 4 869 65 752 60 1 4 876 65 1 4 757 60 1 2 883 65 1 2 763 61 890 66 769 61 897 66 775 61 1 4 905 66 1 2 780 61 1 2 912 67 786 61 3 4 919 67 792 62 927 67 1 4 798 6
15. 9 6 5 M4 45 8 M5 5 5 10 M6 6 6 11 M8 9 15 M 10 11 18 M 12 14 20 Speeds amp Feeds The speeds and feeds for counterbores are approximately 8096 to 85 of those for drills as given on page 15 The counterbore diameter given in the above table is used for this calculation RE SHARPENING Counterbores are re sharpened only by grinding the front cutting edges maintaining the original relief angle of 6 8 Brooke 37 Cutting Tools Limited COUNTERSINKS COUNTERSINKS NOMENCLATURE OVERALL LENGTH CUTTING BODY ANGLE DIAMETER MINIMUM CUTTING Eu DIAMETER DIAMETER OVERALL LENGTH CUTTING ANGLE 77 DIAMETER MINIMUM CUTTING DIAMETER THE CORRECT USE OF COUNTERSINKS A General Guide Countersinks are normally used to produce a 60 or 90 chamfer recess which accommodates the corresponding 60 or 90 screw head They are available in straight or Morse Taper Shank Speeds and Feeds The speeds and feeds for countersinks are the same as those for drills see page 15 and are based on the diameter midway between the largest and smallest diameter of the countersink RE SHARPENING The axial relief is critical to the performance of the countersink and should not be altered When re sharpening grind only the flute face 38 Brooke Cutting Tools Limited REAMERS REAMER NOMENCLATURE OVERALL LENGTH 4 CUTTINGLENGTH RECESS SHANK mc ed BEVEL LEAD ANG
16. a sheet metal drill and clamp the workpiece securely b Possible Cause Using a 2 flute drill to enlarge the diameter of an existing hole Solution Only core drills should be used for this purpose Chipped or Broken Lips a Possible Cause This is usually caused by excessive lip clearance angles behind the cutting edge Solution Check that the lip clearance is as per information on page 28 29 Oversized and Out of Round Holes a Possible Cause Unequal point angles Solution This usually results when hand grinding the point Use a point grinding fixture or machine Possible Cause Unequal cutting edge length lip height Solution When re grinding ensure that the same amount of material is removed from both flanks c Possible Cause Loose spindle or worn drill sleeve Solution Use equipment which is in good condition Possible Cause The workpiece moves Solution The workpiece must be securely clamped b d Brooke 31 Cutting Tools Limited Drill rubbing and not cutting a Possible Cause Too little lip clearance behind the cutting edge Solution Check that the lip clearance is as per information on page 28 29 Cracks in cutting edges a Possible Cause The point is overheated and cooled too quickly when re sharpening Solution Use coolant when grinding or grind in stages quenching frequently in soluble oil Rough hole finish a Possible Cause The drill is blunt Soluti
17. hard Solution Use a HSS Co reamer Tapered or Bell Mouthed holes a Possible Cause Mis alignment of the reamer and the hole Solution Align the reamer and the hole b Possible Cause The machine spindle and or bearings are worn Solution Only use equipment which is in good condition Reamer rubbing and not cutting a Possible Cause Too little reaming allowance in the hole Solution See table of stock removal on page 42 b Possible Cause Reamer re sharpened with too little or no relief on the bevel lead Solution Re grind the bevel lead to a 6 8 relief Oversized holes a Possible Cause Excessive run out on the machine spindle or holding device eg taper sleeve collet or chuck Solution Only use equipment which is in good conditon Brooke 47 Cutting Tools Limited TAPS TAP NOMENCLATURE SIZE OF SQUARE ACROSS FLATS lel y 2 B B E SECTION B B T B LAND SHANK FLUTE CUTTING DIAMETER 2 18 2 WEB m THICKNESS 5 gt 27 514 a gt lt f 5 DIAMETER LEAD 1 ANGLE DIAMETER n 7 No OF THREADS PER INCH p PITCH 48 Brooke Cutting Tools Limited Abbreviations for standard thread forms BA British Association BSB British Standard Brass BSP British Standard Pipe Fine G Series BSPT British Standard Pipe Taper F Series BSW British Standard Whitwo
18. set the lead to correspond with that ofthe tap This also applies on two and multi start taps Preparation of Holes A good hole is a pre requisite of a good thread Some ofthe factors which contribute to inferior threads are b c Out of round holes The thread will be correspondingly out of round Poor surface finish in the hole Size ofthe hole A hole which is too small will cause overloading ofthe tap with the possible breakage Hard spots and abrasive surfaces in the cored holes These holes should be pre drilled Percentage Thread Depth For general purpose work a thread depth of 7596 is recommended A drill size equal to the minor diameter of the tap produces a 100 thread depth This practice is normally recommended fot the following reasons b c 74 100 thread depth requires excessive power to turn the tap with consequent possible breakage 100 thread depth is only 5 stronger than the normal depth of 75 Even a 50 thread depth still produces a thread stronger than its mating bolt Brooke Cutting Tools Limited Basic sizes and tolerance classes To allow for clearance between mating internal and external threads taps are manufactured with oversize allowances added to the basic diameters These basic diameters plus the oversize allowances establish a the minimum effective diameter and NUT TRIANGULAR HEIGHT WIDTH OF FLAT CREST b the m
19. to square centimetres Square feet to square metres Square yards to square metres Square miles to square kilometres Cubic inches to cubic centimetres Cubic feet to cubic metres Cubic yards to cubic metres Pints to litres Gallons to litres Ounces to grams Pounds to kilograms Tons to tonnes 1 000kg Lb sq in to kg sq m Fahrenheit 9 5 C 32 Conversion Factors Metric British To convert Millimetres to inches Metres to feet Metres to yards Kilometres to miles Square centimetres to square inches Square metres to square feet Square metres to square yards Square kilometres to square miles Cubic centimetres to cubic inches Cubic metres to cubic feet Litres to pints Litres to gallons Grams to ounces Kilograms to pounds Tonnes to tons Kg sq mm to Ib sq in Centigrade Celcius 5 9 F 32 Brooke Cutting Tools Limited Multiply by 25 40 0 3048 0 9144 1 60934 6 4516 0 092903 0 836127 2 58999 16 3871 0 028317 0 764555 0 568261 4 54609 28 3495 0 453592 1 01605 703 070 Multiply by 0 0393701 3 28084 1 09361 0 621371 0 1550 10 76391 1 19599 0 3861 0 061024 35 3147 1 76 0 22 0 035274 2 20462 0 984207 0 001422 97 NUMBER AND LETTER DRILL SIZES Decimal Equivalents Decimal Inch mm Inch Wire Decimal Inch 2040 mm Inch Wire 7 6 Brooke mm Inch Wire Decimal Inch Cutting Tools Limited Decimal Inch TOLERANCES Tolerances
20. 0 15 0 25 0 25 0 38 13 24 0 15 0 25 0 25 0 5 0 38 0 76 25 0 25 0 5 0 5 1 0 76 1 27 Tolerances Brooke reamers are manufactured to produce holes to H7 tolerance The tolerance limits shown in the table below are added to the nominal reamer diameter eg nominal diameter 12mm actual diameter 12 008mm 12 015mm Tolerance limits for reamers and hole sizes produced Reamer Diameter Cutting Diameter Hole Diameter Range mm Tolerance Tolerance H7 Above Up to mm mm 1 3 0 004 0 008 0 0 010 3 6 0 005 40 010 0 0 012 6 10 0 006 0 012 0 0 015 10 18 0 008 40 015 0 0 018 18 30 0 009 40 017 0 0 021 30 50 0 012 0 021 0 0 025 Other useful tolerances be found page 99 RE SHARPENING A reamer is only sharpened on the bevel lead which performs the cutting action This operation must be done only by skilled operators on appropriate machine tools When re sharpening it is essential to maintain both the original relief angle of 6 8 and the concentricity of the bevel lead Brooke Cutting Tools Limited 43 REAMER TECHNICAL DATA TYPICAL PHYSICAL PROPERTIES t Type TYPE GRADE HARD TONS Speed Ness piss m min Feed BRINELL FREE CUTTING 150 35 525 12 15 M H 0 3 to 0 4 Carbon 170 40 600 CARBON 0 3 to 0 4 Carbon 248 59 900 7 10 M STEEL 0 4100 7 20
21. 0 5 43 310 2 51 460 1in 11 5 12 18 2 36 90 1in 12 4 46 197 22 23 90 1in 13 4 24 160 2 12 80 1 14 4 5 261 2 2 430 1 15 3 49 60 1 54 330 1in 16 3 34 481 1 47 240 1in 17 3 22 90 1 41 40 1in 18 3 10 580 1 35 290 1in 19 3 0 540 1 30 270 1in 20 2 51 520 1 25 560 1in25 2 17 310 1 8 461 1in 30 1 54 360 57 18 1in 35 1 38 140 49 70 1in40 1 25 560 42 580 1in45 1 16 240 38 120 1in 48 1 11 370 35 481 1in 50 1 8 460 34 231 1in 55 1 2 290 31 140 1in 60 57 171 28 390 Brooke 95 51001 MORSE TAPERS AND BROWN amp SHARPE TAPERS Taper Taper Per Taper Per Included Angle Angle to Centre Line Number mm dia foot on dia Deg Mins Secs Deg Mins Secs Morse 1 0 049881 0 59858 2 51 27 1 25 43 2 0 049951 0 59941 2 51 41 1 25 50 3 0 050196 0 60235 2 52 31 1 26 16 4 0 051938 0 62326 2 58 31 1 29 15 W 5 0 052626 0 63151 3 0 52 1 30 26 6 0 052137 0 62565 2 59 12 1 29 36 0 Brown amp Sharpe 4 0 041867 0 50240 2 23 54 1 11 57 5 0 041800 0 50160 2 23 41 1 11 50 7 0 041789 0 50147 2 23 39 1 11 49 9 0 041737 0 50085 2 23 28 1 11 44 10 0 051343 0 51612 2 27 50 1 13 55 11 0 041750 0 50100 2 23 30 1 11 45 12 0 041644 0 49973 2 23 08 1 11 34 Conversion Factors British Metric To convert Inches to millimetres Feet to metres Yards to metres Miles to kilometres Square inches
22. 00 N mm Similar drills for softer materials such as aluminium mild steel etc with hardness up to 500 N mm are available on special request Coolant Feed Drills Higher production rates can be achieved when deep hole drilling by using coolant feed drills Harmful heat generation at the drill point is prevented by the supply of coolant to the cutting face This allows higher speeds and feeds and improved chip flow thus eliminating the need to clear the flutes by withdrawal Brooke 23 Cutting Tools Limited DRILL TECHNICAL DATA TYPICAL PHYSICAL WORKPIECE MATERIAL PROPERTIES CODE TYPE TONS PER 2 GRADE BRINELL SQ INCH pes FREE CUTTING 150 35 540 0 3 to 0 4 Carbon 170 40 620 101 102 CARBON 0 3 to 0 4 Carbon 248 59 910 141 142 STEEL 0 4 to 0 7 Carbon 206 47 720 447 148 105 amp 0 4 to 0 7 Carbon 286 67 1030 154 164 151 152 Low Alloy Tool Steels 248 59 910 155 161 ALLOY 1 7 STEEL High Alloy Tool Steels 330 75 1150 153 163 Heat Treatable Steels 167 177 Die Steels 380 87 1300 Martensitic 248 54 810 400 Series STAINLESS STEEL Austenitic Work AS ABOVE AS ABOVE Hardening 300 65 1000 300 Series HEAT Inconell Hastello RESISTING y 350 78 1200 AS ABOVE AS ABOVE ALLOYS Nimonic Alloys Commercially Pure 275 65 1000 AS ABOVE TITANIUM AS A
23. 12 or soluble 10 12 Sp Point Str Flute Str Flute Str Flute 3 5 Sol oilor 3 5 light mineral oil 4 7 Str Flute Str Flute Sp Point Dry 12 15 The tapping speeds for fl speeds given uteless taps are 2 3 times higher than the recommended For optimum performance for machine tapping see Colour Band Application CBA section pages 70 amp 71 Brooke Cutting Tools Limited 69 TECHNICAL DATA Surface Treatment Coating TiN TiCN TiAIN coatings are available on request TENSILE MATERIAL TYPES HARDNESS STRENGTH N mm Free Cutting steels 120 400 Structural steel Case carburizing steel 200 700 E Plain carbon steel 250 850 9 o a Alloy steel gt 250 850 Alloy steel gt 250 gt 850 Hardened and tempered steel 350 1200 Alloy steel Hardened and tempered steel gt 350 gt 1200 Free machining Stainless steel 250 850 9 E 9 Austenitic 250 850 o Ferritic Austenitic Ferritic Martensitic 300 1000 Lamellar graphite 150 500 gt 150 gt 500 5 Lamellar graphite 300 1000 E Nodular graphite Malleable Cast Iron 200 700 o Nodular graphite 2200 2700 Malleable Cast Iron 300 1000 E Titanium unalloyed 200 700 5 Titanium alloyed 270 900 1 270 900 Titanium alloyed 350 1200 ES Nickel unalloyed 150 500 Nickel alloyed 270 900 2 i gt 270 gt 900 Nic
24. 2 1 4 934 67 1 2 804 62 1 2 942 68 810 62 3 4 950 68 817 63 958 68 1 2 823 63 1 4 966 68 1 2 829 63 1 2 974 69 836 63 3 4 982 69 1 2 842 64 990 69 1 2 849 64 1 4 999 70 Typical hardness M2 823 876 HV30 63 65 HRC M35 849 920 HV30 64 66 HRC M42 897 966 HV30 66 68 1 2 HRC Depending on the nature ofthe tool these hardnesses may be varied particularly in the case of special tools where different hardnesses may be specified Note Undue reliance should not be placed on a general conversion chart unless it has been tested for a particular material The above chart applies specifically to High Speed Steel Brooke 89 Cutting Tools Limited Section E USEFUL FORMULAE Trigonometry Formulae for the solution of Formulae for the solution of RIGHT ANGLED OBLIQUE ANGLED TRIANGLES TRIANGLES A b A C B a B a Opposite The Sine rule adjacent a a _ b _ SinA 5088 SiC te Sin O The Cosine rule b c 2bc CosA Cos O adjacent _ b a c 2 CosB 05 45 hypotenuse b a b 2ab USEFUL VALUES IN TRIGNOMETRICAL RATIOS For right angled triangles 60 2 4 gt SN 30 45 3 1 ANGLES 30 45 60 Tan O 5 30 1 1 3 3 0 577350 gt 0 500000 5 0 866025 45 1 1 1 2 0 707107 g 0 707107 60 _ 1 3 1 732051 0 866025 gt 0 500000 90 Brooke Cutting Tools Limited
25. 2 X 2 flute drill feed rate Cutting diameter tolerance BROOKE Twist Drills are manufactured to h8 tolerance 2 Flute Drills Cutting Diameter Tolerance on Twist Drills Drill Diameter mm Diameter Tolerance mm Above Up to Plus Minus 3 0 0 014 3 6 0 0 018 6 10 0 0 022 10 18 0 0 027 18 30 0 0 033 30 50 0 0 039 50 80 0 0 046 Back Taper on Fluted Portion The drill diameter is normally reduced over the fluted portion to prevent jamming The amount of back taper is a maximum of 0 08 mm on diameter per 100 mm length Back taper is usually only applied to sizes over 6 mm Brooke 25 Cutting Tools Limited DRILL POINT STYLES Standard Point 118 125 135 599 27 This point is suitable for general purpose drilling Split Point 135 140 145 5 0 252 The split point minimises end thrust and is self centering Long Point 90 125 135 27 Used for wood plastic hard rubber fibres etc Cast Iron Point ADZe C Point a 599 The secondary angle reduces wear on the outer corners 26 Brooke Cutting Tools Limited Heavy Duty Notched Point The notched point reduces end thrust and optimises centre cutting efficiency with chisel strength Itis recommended for hard and high strength materials 125 135 27 Web Thinned Point 118 125 135 x 297 The web thinned point reduces end thrust and improves cent
26. 5 3 5 0 6 4 0 7 4 5 0 75 5 0 8 6 1 7 1 8 1 25 9 1 25 10 1 5 11 1 5 12 1 75 14 2 16 2 18 2 5 20 2 5 22 2 5 24 3 27 3 30 3 5 32 3 5 33 3 5 36 4 39 4 42 4 5 45 4 5 48 5 52 5 56 5 5 Fluteless Tapping Drill Sizes Brooke Cutting Tools Limited Tapping Drill Size mm 1 6 1 8 2 05 2 5 2 75 2 9 3 2 3 3 3 65 3 7 4 1 4 2 4 6 5 5 5 6 6 8 7 4 78 8 5 9 25 9 5 10 2 11 1 12 14 15 5 17 5 19 5 21 24 59 Metric Fine Tapping Size Pitch Drill Size mm 2 0 25 1 75 2 5 0 35 2 15 3 0 35 2 65 3 5 0 35 3 15 4 0 5 3 5 4 5 0 5 4 5 0 5 4 5 6 0 75 5 25 7 0 75 6 25 8 0 75 7 2 8 1 7 9 1 8 10 1 9 10 1 25 8 75 12 1 25 10 75 12 15 10 5 14 1 25 12 75 14 15 12 5 16 1 0 15 16 15 14 5 18 15 16 5 18 2 0 16 20 15 18 5 20 2 18 22 1 5 20 5 22 2 20 24 1 5 22 5 24 2 22 25 1 5 23 5 25 2 23 27 2 25 30 15 28 5 30 2 28 32 1 5 30 5 33 1 5 31 5 36 15 34 5 36 2 0 34 60 Brooke Cutting Tools Limited Metric Fine cont Size 39 40 42 45 48 50 52 BSW Nominal Diameter 3 32 1 8 5 32 3 16 7 32 1 4 5 16 3 8 7 16 1 2 9 16 5 8 3 4 7 8 1 1 1 8 1 1 4 1 1 2 1 3 4 2 BSF 3 16 7 32 1 4 5 16 Pitch Brooke Cutting Tools Limited Tapping Drill Size mm 37 5 38 5 40 5 43 5 46 5 48 5 50 5 Tapping Drill Size mm 1 9 2 55 32 3 7 4 5 5 1 6 5 8 9 3 10 5 12 2 13 5 16 5 19 5 22 25 28 34 39 45 4 7 54 6 8
27. 5 1960 2205 2450 1135 1362 1589 1816 2043 2270 1060 1272 1484 1696 1908 2120 995 1194 1393 1592 1791 1990 885 1062 1239 1416 1593 1770 795 954 1113 1272 1431 1590 725 870 1015 1160 1305 1450 665 798 931 1064 1197 1330 610 732 854 976 1098 1220 570 684 798 912 1026 1140 530 636 742 848 954 1060 455 546 637 728 819 910 400 480 560 640 720 800 350 420 490 560 630 700 320 384 448 512 576 640 250 300 350 400 450 500 210 252 294 336 378 420 160 192 224 256 288 320 Brooke THE CORRECT USE OF DRILLS A guide to successful drilling Make sure the workpiece is securely held and supported Should it bend or move it could cause the drill to break Use a good socket and thoroughly clean both the socket and the taper shank of the drill Do not use steel objects to seat the drill Straight shank drill chucks must be able to hold the drill securely Keep the drill sharp Do not allow it to become blunt as it will require extra grinding to get it sharp again Direct an adequate supply of the recommended coolant to the point of the drill see page 15 Do not allow chips to clog the drill flutes When re sharpening take care to achieve the correct point geometry see page 26 28 and do not overheat the drill when grinding Use core drills for enlarging existing holes 2 flute drills are not designed for this purpose Use the correct drill to suit the application see page 10 13 Deep Hole Drilling A general guide A hole deeper
28. 6 47 700 amp 0 4 to 0 7 Carbon 286 67 1000 5 8 L ALLOY 248 59 900 7 10 M STEEL 330 75 1125 58 M 380 87 1300 2 4 L Martensitic Free Cutting 5 8 M 380 54 810 Martensitic 28 LM STAINLESS Std Grade STEEL Austenitic 58 LM Free Cutting As Supplied Austenitic Std Grade 2 5 L M NIMONIC Wrought 300 67 1000 2 5 ALLOYS 350 78 1200 Titanium Comm 170 40 600 Titanium Comm Pure 200 43 650 7 10 M Titanium Comm Pure 275 65 975 TITANIUM Titanium Alloyed 340 76 1140 2 4 L M Titanium Alloyed 380 85 1275 HSS Standard Grades 225 48 720 TOOL HSS Cobalt Grades 7 10 M STEEL Hot Working Steel 225 54 800 Cold Working Steel TSee Speed Conversion Chart on page 20 21 See table on 43 44 Brooke Cutting Tools Limited cont on page 45 REAMER TECHNICAL DATA TYPICAL PHYSICAL PROPERTIES t GRADE HARD TONS Speed of NESS PER Hie m min Feed BRINELL 12 15 250 52 780 CAST Ductile 10 13 IRONS 12 15 M H Maleable 330 74 1100 Hardened amp Tempered 4 5 M MANGANESE As Supplied 2 3 L STEEL ALUMINIUM As Supplied 3045 H ALLOYS MANGANESE ALLOYS As Supplied 35 60 H ZINC As Supplied 30 45 H ALLOYS Brass Free Cutting 20 35 H Brass Low Leaded 30 45 H Bronze Silicon 15 30 H COPPER As Supplied 10 15 M ALLOYS Bronze Manganese s Supplie Copper 15 45 M H Bronze
29. 63 65 M35 09 4 6 5 2 5 64 66 M42 111 14 15 95 1 8 66 68 5 70 M9V 1 25 4 2 3 5 8 5 3 64 66 M2 is the standard High Speed Steel and is used where toughness is important together with a good standard of wear resistance and red hardness M35 is a development of M2 and contains 5 cobalt which gives improved hardness wear resistance and red hardness It may be used when cutting higher strength materials M42 can be heat treated to very high hardness levels of up to 70 HRC 1 000 HV although normally a slightly lower figure will be employed to retain toughness This steel is ideal for machining higher strength materials and work hardening alloys such as stainless steels nimonic alloys etc Despite its high hardness M42 has good grindability characteristics due to lower vanadium content M9V material is mainly used in the manufacture of machine taps because of its good wear resistance good grinding capabilities high hardness and excellent toughness Cutting tools may shatter eye protection should be worn Brooke 5 Cutting Tools Limited SURFACE TREATMENTS Bright Finish A bright finish tool has no surface treatment and is suitable for general purpose use Blue Finish A blue finish is achieved by steam tempering a thermal process which imparts a non metallic surface to the tool This surface is porous and by absorbing lubricant helps prevent rusting reduces friction and cold wel
30. Aluminium Bronze Commercial 7 15 M Bronze Phospor Soft PLASTICS Hard As Supplied 12 15 M H Reinforced TSee Speed Conversion Chart on page 20 21 See table on 43 Brooke 45 Cutting Tools Limited REAMING PROBLEMS CAUSES AND SOLUTIONS Poor Surface Finish a Possible Cause Incorrect speed and or feed Solution Use the recommended speed feed see page 45 Possible Cause A Worn reamer Solution Do not allow the reamer to become too blunt See page 43 for re sharpening details b c Possible Cause Insufficient or wrong type of lubricant Apply and adequate supply of the correct lubricant to the cutting area See the drill table on page 15 for the recommended lubricants Possible Cause Damaged cutting edges Solution Use a reamer which is in good condition Reamer Chattering a Possible Cause Lack of rigidity in set up Solution Only use equipment which is in good condition and make sure the workpiece is securely held d b Possible Cause Feed too low Solution Use the recommended speed feed see page 45 Reamer showing rapid wear a Possible Cause Too little stock in the hole for reaming causing the reamer to rub and not cut Solution See page 42 for recommended stock removal 46 Brooke Cutting Tools Limited b Possible Cause Speed too high or feed too low Solution Use the recommended speed feed see page 45 c Possible Cause The workpiece material is too
31. BORES COUNTERSINKS REAMERS Nomenclature Selecting the correct reamer Correct use of reamers Reamer Technical Data Re sharpening Reaming problems Causes and Solutions Brooke Cutting Tools Limited 8 9 10 13 14 19 20 21 22 28 29 30 32 33 35 36 37 38 39 40 41 42 43 44 45 43 46 47 CONTENTS cont Page TAPS Nomenclature 48 Selecting the correct tap 55 58 Fluteless Taps 57 amp 65 Tap Tolerances 75 78 Correct use of taps 74 Tap Technical Data 66 71 Re sharpening 78 Tapping Drill sizes 59 65 Thread Forms 50 54 Tapping problems Causes and Solutions 79 85 GENERAL INFORMATION Useful conversion charts and formulae 86 99 IF YOU CANNOT FIND AN ANSWER TO YOUR PROBLEM IN THIS BOOKLET PLEASE CONTACT THE BROOKE FACTORY Brooke Cutting Tools Limited CUTTING TOOL MATERIALS Brooke cutting tools are manufactured from the finest steel available The heat treatment process is controlled by our Metallurgical laboratory using advanced computerised and electronic instrumentation High Speed Steel contains various elements such as Molybdenum Tungsten Cobalt and Vanadium and must be specially heat treated to produce the ideal combination of strength toughness and wear resistance BROOKE products are manufactured from one of the following High Speed Steels depending on the product and application C Cr W V Co Hardness HRC M2 09 4 6 5 2
32. BOVE Commercially Alloyed 350 78 1200 155 Grey Irons CAST AS ABOVE IRONS Nodular Irons 110 300 156 Malleable Irons MANGANESE STEEL AS SUPPLIED AS ABOVE AS ABOVE Wrought Alloys ALUMINIUM Cast Alloys Silicon Alloys 156 AS SUPPLIED AS ABOVE AS ABOVE MAGNESIUM ALLOYS LEADED COPPER ALLOYS Free Cutting Alloys FREE CUTTING BRASS AS ABOVE AS ABOVE MEDIUM TO HIGH LEADED BRASS Moderate LOW TO HIGH SILICON BRONZE COPPER 2 i e MANGANESE BRONZE ALLOYS Machineable Alloys ALUMINIUM SILICON BRONZE AS ABOVE Difficult to Machine COMMERCIAL BRONZE 90 ASABOVE 155 All PHOSPHOR BRONZE 5 10 ALUMINIUM BRONZE Soft PLASTICS Hard AS SUPPLIED AS ABOVE AS ABOVE Reinforced 156 14 Brooke Cutting Tools Limited DRILL TECHNICAL DATA cont CODE TYPE DENOTES RECOMMENDED FEED SPEED CURVE MORSE MORSE COOLANT METRES See LONG EXTRA MIN SERIES LENGTH 18 STANDARD E LENGTH 418 119 SOLUBLE OIL 25 30 201 202 241 242 OR H 46 47 120 121 SEMI SYNTHETIC 15 20 9 203 204 244 245 122 123 DE 10 15 109 110 205 206 251 252 SOLUBLE OIL 124 125 1924 208 254 255 SOLUBLE OIL 10 15 126 EXTREME H PRESSURE 4 8 SOLUBLE OIL EXTREME 12 16 H ASABOVE PRESSURE ASABOVE ASABOVE 261 ASABOVE OR 2 SULPHO CHLORINATED ASABOVE ASABOVE ASABOVE 261 ASABO
33. DRILLS REAMERS TAPS USER GUIDE BROOKE TECHNICAL SERVICES This handbook is intended to help you get maximum performance from BROOKE cutting tools Whilst the information covers most common uses and problems it is not possible to deal with every situation Our trained sales representatives are available to further assist and advise fully backed up by factory technical services FULL SPECIFICATIONS IN BROOKE CATALOGUES Brooke Cutting Tools Ltd is a world class manufacturer producing precision cutting tools to international standards and specifications which include British Standard DIN ISO ANSI and JIS Full details of specifications are listed in our catalogues which are available from leading Industrial Distributors or directly from the Brooke factory PRODUCT RANGE STANDARDS amp SPECIALS The BROOKE range consists of nearly 13 000 standard items and we have a cutting tool available for almost every application Sometimes a special tool is needed and our product engineers at the BROOKE factory can design a special purpose tool to do the job These can also be manufactured to customers specifications orto a sample Brooke Cutting Tools Limited CONTENTS SELECTION OF STEELS SURFACE TREATMENTS DRILLS Nomenclature Selecting the correct drill Drill Technical Data Peripheral Speed Conversion Chart The correct use of drills Re sharpening Drilling problems Causes and Solutions CENTRE DRILLS COUNTER
34. LE SHANK TAPER LEAD SQUARE EB P TAPER LEAD ANGLE SIZE OF SQUARE SECTION A A NO CIRCULAR 0 CIRCULAR LAND 220 2 CLEARANCE CLEARANCE ANGLE ANGLE wi FLUTE e SECTION B B CENTRE HOLE CIRCULAR LAND RADIAL FACE CUTTING EDGE CLEARANCE ANGLE Brooke 39 Cutting Tools Limited SELECTING THE CORRECT REAMER Standard Reamers Parallel Hand Reamers General hand reaming MTS Parallel Machine Reamers General machine reaming Machine Chucking Reamers Parallel Shank General machine reaming for deeper holes MTS Machine Chucking Reamers General machine reaming for deeper holes MTS Taper Bridge Machine Reamers For opening out existing holes alignment on structural steel work Intermediate size reamers are available on request 40 Brooke Cutting Tools Limited Reamers for specific Applications Hand Taper Pin Reamers Metric 3H For reaming holes to suit standard metric taper pins with a taper of 1 50 Hand Taper Pin Reamers Fractional 3H For reaming holes to suit standard fractional taper pins with a taper of 1 48 Brooke 41 Cutting Tools Limited THE CORRECT USE REAMERS A guide to successful reaming Make sure the workpiece is securely held and supported Should it bend or move it could result in a poor finish or cause the reamer to break Use a good morse taper sleeve and thoroughly clean bo
35. Useful formulae for Finding Dimensions of Circles Squares etc D is diameter of stock necessary to turn shape desired E is distance across flats or diameter of inscribed circle C is depth of cut into stock turned to correct diameter TRIANGLE C E 7 side x 0 57735 D side x 1 1547 2E 4 Side 0 0 866 Ex0 5 Dx025 Mu ou SQUARE Aa 27 7 side D x 0 7071 LN D side x 1 4142 diagonal Side 0 0 7071 D x 0 14645 D PENTAGON E side x 1 3764 D x 0 809 D side x 0 7013 E x 1 2361 Side Dx0 5878 D x 0 0955 HEXAGON E side x 1 7321 D x 0 866 D side x 2 E x 1 1547 Side Dx0 5 lt 0 0 067 OCTAGON E side x 2 4142 D x 0 9239 D side x 2 6131 E x 1 0824 Side Dx0 3827 D x 0 038 Brooke 91 Cutting Tools Limited Areas of Plane Figures SQUARE 5 A area 52 1 2 92 0 70714 5 d 1 4145 1414 RECTANGLE A 7 area A ab a a b Ld b a d 5 A b bz a A a RIGHT ANGLED TRIANGLE area bc 2 0 b ACUTE ANGLED TRIANGLE A 7 area bh b a b 7 aue ey IfS 1 a b c then A S 8 a S b 8 6 92 Brooke Cutting Tools Limited OBTUSE ANGLED TRIANGLE A 7 area bh b c s bM bre 2 A S S a S b c CIRCLE A 7 area C circumference 01 3 1416 d
36. VE 5 10 279 SULPHO CHLORINATED ASABOVE SULPHOCHLORNATED 15 25 F ASABOVE ASABOVE 261 ASABOVE EXTREME PRESSURE 279 CHLORINATED OIL 7 11 DRY OR 25 35 DETERGENT ASABOVE ASABOVE ASABOVE ASABOVE water 15 30 K EMULSION 25 30 ASABOVE ASABOVE ASABOVE 261 AS ABOVE PRY OR 4 6 279 NEAT E P OIL SOLUBLE OIL Up to 45 1 25 30 35 ASABOVE ASABOVE ASABOVE ASABOVE LOWVISCOSITY 49 _ 100 3 MINERALOIL SOLUBLE OIL 45 _ 55 1 20 SOLUBLE OIL 30 36 ASABOVE ASABOVE ASABOVE 1 20 L LIGHT MINERAL OIL 15 20 DRY OR 25 30 SOLUBLE OIL lt 20 1 Brooke 15 Cutting Tools Limited ADZe DRILL TECHNICAL DATA TENSILE MATERIAL TYPES HARDNESS STRENGTH HB N mm Free Cutting steels 120 400 Structural steel Case carburizing steel 200 700 z Plain carbon steel 250 850 o a Alloy steel gt 250 850 Alloy steel gt 250 gt 850 Hardened and tempered steel 350 1200 Alloy steel Hardened and tempered steel 2350 21200 2 Free machining Stainless steel 250 850 9 Austenitic 250 850 5 o o Ferritic Austenitic Ferritic Martensitic 300 1000 Lamellar graphite 150 500 gt 150 gt 500 8 Lamellar graphite 300 1000 Nodular graphite Malleable Cast Iron 200 700 9 Nodular graphite 2200 2700 Malleable Cast Iron 300 1000 E Titanium unalloyed 200 700 3 Titanium alloye
37. adius centre suitable for a variety of male centre angles eg 60 82 or 120 can be used as an alternative to type A above 34 Brooke Cutting Tools Limited THE CORRECT USE OF CENTRE DRILLS A guide to successful drilling Recommended Speeds The peripheral speeds for centre drills are the same as for 2 flute drills given on page 14 15 For calculation purposes the nominal diameter given below should be used Centre Drill Nominal Centre Drill Nominal Size Diameter mm Size mm Diameter mm BS 1 3 1 3 BS2 5 1 25 3 BS3 6 1 6 4 BS4 8 2 5 BS5 11 2 5 6 3 BS6 16 3 15 8 BS7 19 4 10 5 12 5 6 3 16 8 20 10 25 Recommended Feeds Use the nominal diameter given above to establish the feed as given on page 19 and then reduce by 40 for centre drills Re sharpening of Centre Drills Centre Drill can be re sharpened on the point only refer to the re sharpening guide for 2 flute drill on page 28 29 Brooke 35 Cutting Tools Limited COUNTERBORES COUNTERBORE NOMENCLATURE SHANK DIAMETER SHANK LENGTH RECESS 7 BODY DIAMETER BODY PILOT PILOT DIAMETER A General Guide Counterbores are used to create seatings for cap screw heads and are therefore identified by the cap screw they suit They are available with straight or Morse Taper shanks 36 Brooke Cutting Tools Limited Cap Screw Pilot Drill Counterbore Size Size mm Diameter mm M3 34 6 M 3 5 3
38. ameter along bottom axis of chart 3 Determine point of intersection of Feed Curve and Drill Diameter 4 Project horizontally from point of intersection to left hand side of chart and read off nearest FEED REV mm 5 Select nearest feed on drilling machine within x 2096 of chart figure 18 Brooke Cutting Tools Limited General Drilling Feeds mm per revolution Drill Drill Diameter Diameter reed Range mm Range Range mm Range 1 3 0 03 to 0 075 16 20 0 25 to 0 53 3 5 0 05 to 0 18 20 25 0 28 to 0 56 5 8 0 10 to 0 28 25 30 0 30 to 0 60 8 12 0 15to 0 35 30 40 0 35 to 0 68 12 16 0 20 to 0 45 Over 40 0 40 to 0 75 When setting to drill material of unknown machinability the slowest speed and lightest feed should be used and these should be gradually increased until optimum output per regrind is obtained HELIX ANGLE OR SPIRAL QUICK SPIRAL Brooke 19 Cutting Tools Limited TO rpm CONVERSION CHART Cutting Tools Limited 50 60 70 80 90 100 per Minute 15910 19092 22274 25456 28638 31820 7950 9540 11130 12720 14310 15900 5300 6360 7420 8480 9540 10600 3975 4770 5565 6360 7155 7950 3180 3816 4452 5088 5724 6360 2650 3180 3710 4240 4770 5300 2275 2730 3185 3640 4095 4550 1990 2388 2786 3184 3582 3980 1765 2118 2471 2824 3177 3530 1590 1908 2226 2544 2862 3180 1445 1734 2023 2312 2601 2890 1325 1590 1855 2120 2385 2650 1225 1470 171
39. d 270 900 me 2270 7900 Titanium alloyed 350 1200 m Nickel unalloyed 150 500 Nickel alloyed 270 900 2 z gt 270 gt 900 Nickel alloyed 350 1200 Copper 100 350 x 8 Beta Brass Bronze 200 700 8 Alpha Brass 200 700 High strength Bronze 470 1500 Al Mg unalloyed 100 350 alloyed Si 0 5 150 500 25 Al alloyed Si 0 5 120 400 o lt 10 A alloyed Si gt 10 198 400 Al alloys Mg alloys on z Thermoplastics 25 a 9 Thermosetting plastics So Reinforced plastic materials 16 Brooke Cutting Tools Limited ADZe DRILL TECHNICAL DATA cont NORMAL DRILL TYPE amp SURFACE SPEED FEED CHIP SURFACE METRES CURVE FORM TREATMENT PER MINUTE see Page 18 Long Chip 35 45 H extra long TN 50 70 J Long Chip 25 35 H middle long TiN 40 50 J lon Long Chip 25 30 G 9 35 40 1 lon Long Chip 25 30 G 9 35 40 lon Long Chip 15 20 E 9 25 30 long Long Chip 15 20 E TiN TiCN TiAIN 20 25 G Long Chip 18 21 E mede TiN 27 32 lon Long Chip 8 10 K 9 12 15 M long Long Chip 10 15 TiN TiCN 16 22 G Cast Iron 30 35 G extra short 25 55 Cast Iron 25 30 G TAIN 35 45 i Cast Iron 18 21 E middle sh
40. ding resulting in increased tool life Steam tempered products can successfully be used at slightly increased machining rates or on more difficult to machine materials Gold Oxide This is a metallic brown coloured surface treatment achieved by a low temperature temper and is normally only used on cobalt products for identification purposes Nitriding Nitriding imparts a hard surface to the tool and is used for prolonging tool life and machining difficult to machine materials Because nitriding makes the edge more brittle care must be exercised in the type of application Nitrided tools are normally also steam tempered Titanium Nitride Coating TiN TiN coating is a very hard gold coloured surface coating a few microns thick which is applied by means of a complex process called Physical Vapour Deposition PVD by advanced modern equipment The coating is non metallic and therefore reduces cold welding In certain applications increased speed and feed rates can be achieved because of a The hardness of the coating b The reduction in cutting force required due to a decrease in friction between the tool and the workpiece Tool performance will deteriorate after re sharpening 6 Brooke Cutting Tools Limited TiCN Titanium Carbonitride The addition of carbon to TiN results in a significant increase in the hardness of TiCN over TiN TiCN also has a much lower coefficient offriction which enhances the surface finish of c
41. drill point is prevented by the supply of coolant to the cutting face This allows higher speeds and feeds and improved chip flow thus eliminating the need to clear the flutes by withdrawal Brooke 23 Cutting Tools Limited Core Drilling Core Drill Nomenclature OVERALL LENGTH BODY RECESS SHANK FLUTE LENGTH DIAMETER CHAMFER LENGTH LIP LENGTH LIP CLEARANCE ANGLE Tt LAND WEB i LAND BODY BODY CLEARANCE CLEARANCE FLUTES DIAMETER 4 FLUTES DIAMETER Core Drills Cutting Diameter Tolerance on Core Drills Core Drill Diameter mm Diameter Tolerance mm Above Up to Plus Minus 6 0 0 018 6 10 0 0 022 10 18 0 0 027 18 30 0 0 033 30 50 0 0 039 24 Brooke Cutting Tools Limited A Guide to Core Drilling Core drills are only used for enlarging diameters of existing holes whether drilled punched or cored Having no point the drill is only able to cut on the chamfer The maximum amount of material that be removed is restricted by the chamfer root diameter to 60 of the core drill diameter Because of its multi flute construction the core drill gives better hole size and surface finish than a two flute drill Two flute drills should not be used to enlarge existing holes as they will tend to chip and break Speed and Feed rates for Core Drills Speed As for 2 flute drills Feed 3 Flute 1 to 1 5 X 2 flute drill feed rate 4 Flute 1 5 to
42. e tapping speeds for fl than the recommended speeds given Brooke Cutting Tools Limited uteless taps are 2 3 times higher cont on page 68 67 TECHNICAL DATA TYPICAL PHYSICAL PROPERTIES TYPE GRADE HARD TONS NESS PER N mm BRINELL SQ IN Grey Ductile 240 52 780 CAST IRONS Maleable 2 Hardened Tempered ALUMINIUM Long Chip ALLOYS Short Chip As Supplied MANGANESE ALLOYS As Supplied ZINC ALLOYS As Supplied Brass Free Cutting Brass Low Lead Bronze Silicon Bronze Manganese COPPER Copper Free Machining ALLOYS Copper Electrolytic As Supplied Bronze Aluminium Bronze Commercial Bronze Phosphor Soft PLASTICS Hard As Supplied Reinforced 68 Brooke Cutting Tools Limited TECHNICAL DATA cont RECOMMENDED ALTERNATIVE TAP TYPE TAP TYPE TAP PERIPHERAL THROUGH BLIND THROUGH SPEED LUBRICANTS HOLE HOLE HOLE HOLE m min 5 10 Dry soluble oil Str Flute Str Flute Sp Point or paraffin 4 8 20 25 Sol oil or Fluteless Fluteless Sp Point Sp Flute light material 10 15 oil Sp Point Sp Flute Str Flute Str Flute 15 20 Sul B Oil Fluteless Fluteless Str Flute Str Flute 15 20 Soluble Oil Sol oil or 15 20 light mineral oil Fluteless Fluteless Str Flute Str Flute 25 30 10 12 Sp Point Str Flute Str Flute Str Flute 3 5 Fluteless Fluteless Sp Point Sp Point 15 20 Chlorinated 8
43. ed hole b d e f g 80 Possible Cause The flutes are clogged by chips Solution Use a spiral point or a spiral flute tap Possible Cause Distortion of the walls in a thin walled workpiece Solution Use a multi fluted tap Possible Cause The threads on the tap are broken Solution Use a tap which is in good condition Possible Cause Lack of or the wrong type of lubricant Solution Apply an adequate supply and the correct type of lubricant to the cutting area See page 67 Possible Cause Using the incorrect or unsuitable tap for the material Solution Use the recommended tap for the material See page 55 58 Possible Cause Tap hitting the bottom of the hole Solution Allow sufficient clearance at the bottom of the hole Possible Cause Incorrect rake angle Solution Use the recommended tap for the material See page 55 58 Brooke Cutting Tools Limited Excessive Tap Wear a Possible Cause Mis alignment of the tap and the hole Solution Care must be taken to align the tap with the hole before starting totap b Possible Cause Lack of or the wrong type of lubricant Solution Apply an adequate supply and the correct type of lubricant to the cutting area c Possible Cause The material is abrasive Solution i Use the correct type of tap ii Use a surface treated tap d Using the incorrect tap Solution i Use a tap with the correct lead
44. g Drill Size mm 8 8 11 8 15 5 19 21 24 5 28 5 31 40 45 5 51 5 57 8 6 11 5 15 0 18 5 24 0 30 25 39 0 45 0 56 5 9 1 12 0 15 5 19 0 24 5 30 5 39 4 45 5 57 5 Nominal Tapping Diameter TPI Drill Size mm 1 8 27 84 1 4 18 11 0 3 8 18 14 25 1 2 14 17 5 3 4 14 23 0 1 11 1 2 29 0 1 1 4 11 1 2 37 5 1 1 2 11 1 2 43 5 2 11 1 2 55 5 Fluteless Taps Fluteless taps are used for cold forming threads in ductile materials and have the following advantages a Increased strength and tap life resulting from i Elimination of flutes which reduce the shear strength of the tap ii Thelackof cutting edges which in a conventional tap wear and break down iii The lack of chips which sometimes causes jamming b Better blind hole tapping due to the lack of chips and problems relating to chip removal c Higher productivity due to faster tapping speeds d Stronger threads FLUTELESS TAP STRONGER THREAD T GRAIN FIBRE OF METAL UNBROKEN BURNISHED THREAD NO CHIPS The grain fibres of the metal are not cut but displaced to form the threads which are stronger than cut threads It is accepted that a 60 cold formed thread is as strong as a 75 cut thread Brooke 65 Cutting Tools Limited TECHNICAL DATA TYPICAL PHYSICAL PROPERTIES TYPE GRADE HARD TONS NESS PER N mm BRINELL
45. ii Use a surface treated tap e Possible Cause Incorrect rake angle Solution Use the recommended tap for the material See page 55 58 Over Heating of tap a Possible Cause Lack of or the wrong type of lubricant Solution Apply an adequate supply and the correct type of lubricant to the cutting area Possible Cause The tap is too dull Solution Use a tap which is in a good condition c Possible Cause The wrong type of tap is used Solution Use the recommended tap See page 55 58 b 81 Cutting Tools Limited Possible Cause Excessive tapping speed is applied Solution Use the recommended tapping speed See page 67 Bell Mouthed Tapped Hole b d e Possible Cause Mis alignment of the tap and the hole Solution Care must be taken to align the tap with the hole before starting totap Possible Cause The workpiece is not rigidly held Solution Secure the workpiece Possible Cause Excessive pressure is applied when starting to tap Solution Only sufficient pressure to initiate self feeding should be applied Possible Cause Insufficient number of threads on the lead Solution Use a tap with a longer lead Possible Cause The drilled hole is too small Solution Use the recommended drill size See page 59 64 Over size tapped hole b 82 Possible Cause Using the incorrect tap Solution Use the recomme
46. inimum major diameter BOLT CREST RAD BASIC DEPTH OF THREAD RAD MINOR DIA EFFECTIVE DIA ROOT mur 77 vo Brooke Cutting Tools Limited MINOR DIA EFFECTIVE DIA MAJOR DIA MAJOR DIA 75 Limits of Tolerance Effective Diameter The tolerance is the amount of variation allowed in the manufacture of the tap This tolerance is added to the minimum effective diameter to establish the maximum effective diameter It follows that Basic Effective Oversize Minimum Effective Basic Effective Oversize tolerance Maximum Effective The effective diameter can only be measured with special tap measuring equipment Major Diameter The minimum major diameter is established by adding the oversize allowance to the basic major diameter the nominal thread size Therefore on measurement the major diameter of the tap is larger than the nominal thread size and must not be used to judge the size ofthe tap The maximum major diameter of the tap is governed by the thread form andis therefore not subject to a tolerance 76 Brooke Cutting Tools Limited Tap Tolerance Classes Relationships of Tap Classes to Nut Tolerances TOLERANCE BAND TOLERANCE BAND Metric Threads NUTS 8H MAX 6G 7H MAX MAX 5G 6H MAX MAX 4G 5H MAX MAX 4H
47. is considered a deep hole Deep holes are successfully drilled by reducing speed and feed rates as shownin the table on page 23 Care must be taken not to clog the flutes with chips In very deep holes it may be necessary to withdraw the drill frequently to clear the flutes Extra length drills should be used with a guide bush as close to the workpiece as possible to support the drill 22 Brooke Cutting Tools Limited Recommended Speeds for Deep Holes Depth of Hole Speed Reduction 3 X Drill Diameter 1096 4 X Drill Diameter 20 5 x Drill Diameter 30 More than 6 X Drill Diameter 40 Recommended Feeds for Deep Holes Depth of Hole Feed Reduction 3 to 4 X Drill Diameter 10 5 to 8 X Drill Diameter 20 Extra Length Deep Hole Drills ADZe Long Chip The BROOKE Deep Hole drill has a specially shaped flute form commonly known as Parabolic which gives rigidity for deep hole drilling and improves chip flow enabling the full depth of the hole to be drilled without withdrawal These drills are of special robust design for use on tougher materials such as steels and cast irons with hardness up to 1000 N mm Similar drills for softer materials such as aluminium mild steel etc with hardness up to 500 N mm are available on special request Coolant Feed Drills Higher production rates can be achieved when deep hole drilling by using coolant feed drills Harmful heat generation at the
48. kel alloyed 350 1200 Copper 100 350 5 Beta Brass Bronze 200 700 a 8 Alpha Brass 200 700 High strength Bronze 470 1500 Al Mg unalloyed 100 350 alloyed Si 0 5 150 500 33 3 Al alloyed Si gt 0 5 5 9 lt 10 120 400 lt Al alloyed Si gt 10 420 400 Al alloys Mg alloys 9 9 Thermoplastics os 50 Thermosetting plastics 5 oz Reinforced plastic materials 70 Cutting Tools Limited TECHNICAL DATA cont Recommended X Suitable NORMAL SPEED M Min RECOMMENDED TAP TYPE STANDARD coaten YELLOW WHITE extra long 12 18 27 x e middle long 12 18 27 long 10 18 24 e long 10 18 24 long 8 9 15 long 5 9 15 middle 9 18 24 long 6 9 15 long 5 8 15 extra short 11 18 27 extra short 8 9 18 middle short 11 18 27 x e middle short 8 9 18 e extra long 8 9 15 e middle short 9 12 18 x middle short 6 6 12 x extra long 9 12 18 e long 5 6 12 e x long 4 5 11 x extra long 11 15 24 e middle short 30 43 55 e x long 18 40 49 short 5 6 12 extra long 15 24 30 e middle 30 43 52 middle short 18 30 36 x e short 15 24 30 x extra long 27 a e short 11 15 21 extra short 8 9 15 x Brook Cutting Tools Limited 71 PERIPHERAL SPEED
49. nded tap See page 55 58 Mis alignment of the tap and the hole Solution Care must be taken to align the tap with the hole before starting totap Possible Cause Lack of or wrong type of lubricant Solution Brooke Cutting Tools Limited Apply an adequate supply and the correct type of lubricant to the cutting area d Possible Cause Incorrect rake angle Solution Use the recommended tap for the material See page 55 58 Tap binding in the hole a Possible Cause Using the incorrect tap Solution Use the recommended tap See page 55 58 Possible Cause The drilled hole is too small Solution Use the recommended drill size See page 59 64 c Possible Cause Lack of or the wrong type of lubricant Solution Apply an adequate supply and the correct type of lubricant to the cutting area See page 67 Possible Cause The flutes are clogged with chips Solution Use a spiral point or a spiral flute tap e Possible Cause Incorrect rake angle Solution Use the recommended tap for the material See page 55 58 b d Flutes clogged with chips a Possible Cause Using the incorrect tap Solution Use a spiral point or spiral flute tap b Possible Cause Lack of or the wrong type of lubricant Solution Apply an adequate supply and the correct type of lubricant to the cutting area Brooke 83 Cutting Tools Limited b d e f
50. oke Cutting Tools Limited SELECTING THE CORRECT Short Machine and Hand Taps PER For general purpose hand or machine use for short production runs Best suited for materials which do not present chip disposal problems Machine Taps Spiral Point Tap Sometimes called a gun nosed tap For machine use on through holes Suitable for a wide range of materials The gun nose creates chip disposal ahead of the tap while the flute geometry allows an adequate supply of lubricant to the cutting area making higher tapping speed possible Spiral Flute Tap SSS Mainly for work in blind holes and on ductile materials such as aluminium and zinc alloys which produce long stringy chips The taps have a 35 right hand helix The flute shape eliminates clogging and jamming resulting in improved tap life Brooke 55 Cutting Tools Limited Serial Taps SIISII ITITS A TEYYVYVYYVVYVYYS For general purpose machine or hand use in tough materials producing accurate threads with a high finish Used in sequence to remove most of the material in stages before finally sizing with the Finishing tap Pipe Taps For machine use on pipe work for parallel threads 01 For machine use on pipe work for tapered threads Special taps are available on request 58 Brooke Cutting Tools Limited RECOMMENDED TAPPING DRILL SIZES For 75 thread depth Metric Coarse Size Pitch 2 0 4 2 5 0 45 3 0
51. omponents machined with TiCN coated tools higher productivity can be achieved on a wide range of materials but in particular stainless steel titanium and nickel based alloys TiALN Titanium Aluminium Nitride In addition to a higher hardness than both and the aluminium in the coating imparts a much greater oxidation stability This is as a result of a very thin film of Aluminium Oxide being formed on the surface of the TiALN The film is self repairing leading to additional increased service life These improvements allow the coating to withstand much higher temperatures which in turn allows increased cutting conditions especially useful when machining Cast Iron and tough steels Brooke 7 Cutting Tools Limited DRILLS DRILL NOMENCLATURE TANG MORSE TAPER SHANK RECESS OVERALL LENGTH BODY DIAMETER 8 Brooke Cutting Tools Limited DRILL NOMENCLATURE BODY CLEARANC DIAMETER WEB THICKNESS CHISEL ANGLE POINT ANGLE CHISEL LIP CLEARANCE ANGLE DETAILED VIEW OF LIP CLEARANCE Brooke 9 Cutting Tools Limited SELECTING THE CORRECT DRILL Drills for general use These twist drills are designed to drill the common materials under normal operating conditions The following standard drills are available ex stock from Brooke Jobber Drills General purpose drilling Long Series Drills General purpose long reach drilling Stub Drills
52. on Re sharpen as per information on page 28 29 b Possible Cause Inadequate supply of coolant to the point Solution The coolant must reach the point of the drill Drill breaks at flute runout a Possible Cause The workpiece moves during drilling Solution The workpiece must be securely clamped Possible Cause The flutes are clogged with swarf Solution Clear the flutes by frequently withdrawing the drill or use a drill more suited to the material e g a ADZe Long drill for aluminium c Possible Cause Using the wrong type of drill e g using a jobber drill for thin b material Solution See pages 10 to 13 for the correct drill to suit the application 32 Brooke Cutting Tools Limited CENTRE DRILLS CENTRE DRILL NOMENCLATURE OVERALL LENGTH PILOT FLUTE LENGTH LENGTH BODY DIAMETER PILOT DIAMETER lt TYPE B RADIUS TYPE R Brooke 33 Cutting Tools Limited SELECTING THE CORRECT CENTRE DRILL For general centering operations on workpieces requiring additional maching between centres TYPE A TYPE B Protected Centre Sometimes called Bell Type gt The 60 surface produced by this centre drill is recessed below the surface ofthe workpiece and is therefore protected from damage TYPE R Radius The type R centre drill is also used for general centering operations but produces a r
53. ort 25 35 G Cast Iron 12 17 E middle short TAIN 22 26 Long Chip 20 25 E extra long TICN 30 35 Short Chip 13 17 E middle short TICN 20 25 G i Short Chip 5 6 middle short TICN 7 11 Long Chip 12 16 G ena long 20 25 long Long Chip 6 8 G TiCN TiAIN 10 12 long Long Chip 5 6 TiCN TiAIN 10 12 E Long Chip 55 65 extra long TN 80 95 N Short Chip 60 70 L middle short TN 90 105 N Long Chip 30 40 L long TiN 45 50 N Short Chip 27 33 K enon TN 40 50 M Long Chip 75 85 extra long TIN 110 125 N Long Chip 65 75 N TiN 100 115 N i Short Chip 55 65 L middle short TN 80 100 N Short Chip 27 33 K short TN 40 50 M Long Chip 75 85 L extra Tong 110 125 N Short Chip 55 65 J Priore 80 100 L Cast Iron 15 20 J extra short 20 30 L Brooke Cutting Tools Limited 17 DRILL FEED CURVE CHART DRILL FEEDS o to 07 L 0 6 K 0 5 J H 04 G F 0 3 is D 0 2 E 22 1 0 10 0 09 TH 0 08 m 0 07 006 A LL 0 05 0 04 0 03 0 02 0 01 1 2 3 4 5 6 7 8910 20 30 40 50 DRILL DIAMETER mm HOW TO USE THE DRILL FEED CHART 1 Locate Feed Curve as given in the application data pages 15 amp 17 on the right hand side of the drill feed chart 2 Locate Drill Di
54. re cutting efficiency ADZe L Point 2 10 D x 125 135 lt The 130 special notched UX point style provides self centering easier penetration improved hole accuracy and improved load distribution This special notch geometry gives a corrected rake angle of 15 which provides strong point for harder materials as well as preventing snatching with materials such as Aluminium Brass Bronze and Plastics Available on UDL and UDS drills Brooke 27 Cutting Tools Limited Part Split Point 2 EN 140 145 The 130 part split point is similar to the conventional split point The part split point has a wider chisel edge Provides easy penetration self centering and optimises centre cutting efficiency with chisel strength Common Re Sharpening Errors on Standard Drill Points I A LIP LIP CLEARANCE CLEARANCE ANGLE ANGLE TOO GREAT TOO SMALL CHISEL ANGLE CHISEL ANGLE TOO GREAT TOO SMALL 28 Brooke Cutting Tools Limited LIPS UNEQUAL LENGTH DIFFERENCE IN RELATIVE LIP HEIGHT DIFFERENCE IN RELATIVE LIP HEIGHT WILL DRILL AN OVERSIZE HOLE UNEVEN WEB WEB THINNING THINNING TOO GREAT Web thinning is recommended for 1 restoring chisel edge to the original length after several regrinds 2 larger drills where the machine thrust is limited 3 difficult materials Lip Clearance Angle Drill Size mm Angle Up to 3 18 24 3 1 6 14 18 6 1 12 10 14 12
55. rth BSF British Standard Fine M Metric MF Metric Fine NPS National Pipe Straight NPT National Pipe Taper UNC Unified National Coarse UNF Unified National Fine Brooke 49 Cutting Tools Limited THREAD FORMS ISO METRIC 60 h 0 866P 0 541 0 1443P WHITWORTH r H h Los 0 960491 h 0 640327P r 0 137329 50 Brooke Cutting Tools Limited UNIFIED 1 8H 60 Y 3 H 5 8H AE 1 4H 0 86603 1 4H 0 21651P 5 8H 0 54127P 1 8H 0 10825P BA 47 5 H h 1 1363365P 0 6P S 0 26817P 0 18083P Brooke 51 Cutting Tools Limited BSPT 55 H h di 90 H 0 960237P d MAJOR DIAMETER AT GAUGE PLANE h 0 640327P 91 MINOR DIAMETER AT GAUGE PLANE r 0 137278P TAPER 1 IN 16 ON DIAMETER BSB 55 r H h 0 86603P h 0 5237P 0 1667 52 Brooke Cutting Tools Limited NPS AT GAUGE PLANE 60 Y H h f P 0 866P h 0 8P f 0 033P NPT 60 1 d H h 1 al H 0 866P d MAJORD h 0 8P d MINOR DIAMETER AT GAUGE PLANE f 0 033P TAPER 1 IN 16 ON DIAMETER Brooke 53 Cutting Tools Limited 11 17 per h 0 5P CLEARANCE F 0 3707P 0 3707P 0 256 X MAJOR DIAMETER ALLOWANCE TRAPEZOIDAL 17 1 2 7 h 0 5 CLEARANCE 54 Bro
56. tap 78 Brooke Cutting Tools Limited TAPPING PROBLEMS CAUSES AND SOLUTIONS Damaged tap threads in the hole a Possible Cause Mis alignment of the tap with the hole before starting to tap Solution Care must be taken to align the tap with the hole before starting totap Possible Cause The tap is too dull Solution Use a tap which is in good condition c Possible Cause Work hardened skin in the drilled hole Solution Work hardening can be avoided when drilling by using the correct speeds and coolants See page 15 Use serial taps Possible Cause Incorrect rake angle Solution Use the recommended tap for the material See page 55 58 b d Poor finish of the thread a Possible Cause Using the incorrect tap Solution Use the recommended tap Possible Cause The drilled hole is too small Solution Use the recommended drill size See page 59 64 c Possible Cause The tap is too dull Solution Use a tap which is good condition Possible Cause Insufficient number of threads on the lead Solution Use atap with the correct lead Brooke 79 Cutting Tools Limited b d f Possible Cause Mis alignment of the tap and the hole Solution Care must be taken to align the tap with the hole before starting totap Possible Cause Incorrect rake angle Solution Use the recommended tap for the material See page 55 58 Torn threads in the tapp
57. th the sleeve and the taper shank of the reamer As areamer only cuts on the bevel lead and not on the peripheral land it is essential to keep it sharp A blunt reamer wears on the outer corners on the bevel lead resulting in a poor fininsh undersize holes and increased torque See page 43 for re sharpening details Direct adequate supply of the recommended lubricant to the cutting area When reaming high tensile materials an improved surface finish can be achieved by using chlorinated or sulphurised oils Stock Removal Reamers are used to produce accurate holes with a good surface finish It is common fault to leave too little stock for removal by reaming This results in a rubbing action and excessive wear of the reamer The table below shows approximate amounts of stock to be removed by reaming Machine Reamers Size of Reamed Pre Drilled Pre Core Hole mm mm Drilled Above Up to mm 1 5 0 3 0 2 1 5 3 0 3 0 2 3 6 0 3 0 2 6 13 0 4 0 25 13 25 0 5 0 3 25 0 5 0 3 Hand Reamers The hand reaming allowance should be approximately two thirds of the machine reaming allowance 42 Brooke Cutting Tools Limited Feed Conversion Table Reamer Diameter Feed mm rev Range mm Above Up to Light L Medium M Heavy H 1 5 0 005 0 025 0 012 0 05 0 025 0 075 15 3 0 025 0 05 0 05 0 1 0 075 0 15 3 6 0 05 0 1 0 1 0 15 0 15 0 25 13 0 1 0 15
58. than 3 times its diameter is considered a deep hole Deep holes are successfully drilled by reducing speed and feed rates as shownin the table on page 23 Care must be taken not to clog the flutes with chips In very deep holes it may be necessary to withdraw the drill frequently to clear the flutes Extra length drills should be used with a guide bush as close to the workpiece as possible to support the drill 22 Brooke Cutting Tools Limited THE CORRECT USE OF DRILLS A guide to successful drilling Make sure the workpiece is securely held and supported Should it bend or move it could cause the drill to break Use a good socket and thoroughly clean both the socket and the taper shank of the drill Do not use steel objects to seat the drill Straight shank drill chucks must be able to hold the drill securely Keep the drill sharp Do not allow it to become blunt as it will require extra grinding to get it sharp again Direct an adequate supply of the recommended coolant to the point of the drill see page 15 Do not allow chips to clog the drill flutes When re sharpening take care to achieve the correct point geometry see page 26 28 and do not overheat the drill when grinding Use core drills for enlarging existing holes 2 flute drills are not designed for this purpose Use the correct drill to suit the application see page 10 13 Deep Hole Drilling A general guide A hole deeper than 3 times its diameter
Download Pdf Manuals
Related Search