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 UNITED STATES OF AMERICA. 
 
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THE 
 
 BOSTON MACHINIST. 
 
 BEING A COMPLETE 
 
 SCHOOL FOR THE APPRENTICE 
 
 A8 WELL AS THE 
 
 ADVANCED MACHINIST. 
 
 SHOWING HOW TO MAKE AID ERY TOOL IN EVERY 
 
 BRANCH OF TH1 SS. 
 
 WITH A TKEATI8E ON 
 
 SCREW AND GEAR CUTTING. 
 
 ISy WALTER FITZGERALD, 
 
 Inventor and Mechanical Engineer. 
 
 NEW YORK: 
 JOHN WILEY & SON, 535 BROADWAY. 
 
 1866. i 
 
-v 
 
 
 4 
 
 ~\ 
 
 
 /)- 
 
 Entered according to Act of Congress, in the year 1866, by 
 
 JOHN WILEY & SON, 
 
 In the Clerk's Office of the District Court of the United States, for 
 the Southern District of New York. 
 
 NEW YORK PRINTING OOMPAN1, 
 
 81, 83, and 85 Centre St. 
 
CONTENTS. 
 
 PAGE 
 
 1. The Apprentice's first lesson. 9 
 
 2. Lesson second 9 
 
 3. Lesson third 11 
 
 4. Lesson fourth 11 
 
 5. Lesson fifth 19 
 
 6. To drill a large hole in the end of a shaft 13 
 
 7. Straightening Shafting ' . . 
 
 8. Setting a Lathe straight to turn Shafting U 
 
 9. Turning Shafting 15 
 
 10. Setting a Lathe to turn Tapering 16 
 
 11. Tools for different kinds of Turning 18 
 
 12. Planer Tools 
 
 13. Chucking Pulleys 23 
 
 14. Setting the Chuck-rest 
 
 15. To drill a hole where you have no Reamer 
 
 16. Boring a hole with a boring tool. 
 
 17. Squaring, or Facing up Cast Iron Surfaces 26 
 
 18. Scraping Cast Iron smooth I 7 
 
 19. Keep your Lathe clean. 27 
 
IV CONTENTS. 
 
 PAGE 
 
 20. Boring Holes and Boring Arbor 27 
 
 21. To make a Boring Arbor and Tool, that will not 
 Chatter 28 
 
 22. Gearing a Lathe for Screw-cutting 29 
 
 23. Cutting a Screw in an Engine Lathe 30 
 
 24. Cutting Square Thread-Screws 31 
 
 25. Mongrel Threads 32 
 
 26. Planing Metals 33 
 
 27. Planing perpendicularly 33 
 
 28. Planing a Key-Way .33 
 
 29. Planing a T-shaped Slat 34 
 
 30. To Plane a Gibe-Rest or Slide 35 
 
 31. Note 35 
 
 32. Gear Cutting 36 
 
 33. Depth of Teeth 36 
 
 34. Measuring to find the Number of Teeth 37 
 
 35. Bevel Gears 38 
 
 36. The different Styles of Filing 39 
 
 37. To File a Square Hole 40 
 
 38. Draw-Filing and Finishing 40 
 
 39. Lining Boxes with Babbitt Metal 40 
 
 40. Making Lining Metal 41 
 
 41. Putting Machines together 41 
 
 42. Working Steel for Tools 42 
 
 43. Annealing Steel 43 
 
 44. Water Annealing 44 
 
CONTEXTS. V 
 
 PAGE 
 
 ■\:>. Eardening Steel Tools of the various Kinds 44 
 
 4G. Dipping tools when hardening 46 
 
 47. Dipping a half-round file or reamer 40 
 
 48. Dipping a fluted reamer properly 47 
 
 49. Tempering tools 47 
 
 60. Fancy tool making 48 
 
 51. Making collets, or drill sockets 48 
 
 52. To make a collet properly 49 
 
 53. To make a collet for upright drills 50 
 
 54. Making drills 50 
 
 55. Spiral drills 60 
 
 66. Cutting the Spiral Grooves 53 
 
 67. Flat Drills for Chucking 54 
 
 58. Tap and Reamer Wrenches 55 
 
 59. Proportions for Tap and Reamer Wrenches 
 
 60. Tap and Reamer Wrenches. Size two 56 
 
 61. Tap and Reamer Wrenches, Size three 56 
 
 62. Wrenches for Taps and Reamers, Size four 56 
 
 63. Wrenches for Taps and Reamers, Size five 58 
 
 64. Wrenches for Taps and Reamers, Size six 58 
 
 65. Making Taps. The Turning 58 
 
 66. Proportions of Screws 59 
 
 67. Cutting the Threads 61 
 
 68. Square Thread-screws 63 
 
 69. Mongrel or half Y, half square Threads 63 
 
 70. Fluting Taps 64 
 
VI CONTENTS. 
 
 PAGE 
 
 71. How to go to work 64 
 
 72. Fluted Reamers , 67 
 
 73. How to make a Fluted Reamer 67 
 
 74 Half-round Reamers 71 
 
 75. Rose Reamers 71 
 
 76. Counter-boring Tools 72 
 
 77. Making Dies for Screw-cutting 72 
 
 78. Milling Tools 73 
 
 79. Proportionate numbers of Teeth, in different Sizes. . .74 
 
 80. Proportions of Broad Cutters 74 
 
 81. Punches and Dies 76 
 
 82. Making Gauges 77 
 
 83. Note on Balance-wheels 77 
 
 84. A few words as to Master Mechanics 78 
 
PREFACE 
 
 In preparing this work, the author has endeavored 
 to give to the Mechanic a volume that he can readily 
 understand, though he may not have a full know- 
 ledge of the scientific terms commonly used in works 
 of this kind. He has also aimed to give a full ex- 
 planation of every subject treated of in as few words 
 as possible. He had thought of adding an article on 
 the proper speed of turning and planing metals; but 
 as they vary so much in hardness, it il almost impos- 
 sible to lay down any safe rule, and he has therefore 
 concluded to omit it. He hflfl llflO purposely omitted 
 the subjects of Geometry and Machine Drawing, 
 as they would have extended the volume beyond its 
 proposed size; and, besides, there are already pub- 
 lished many good treatises on these subjects. Ask- 
 ing, therefore, that due allowance may be made for 
 all omissions and imperfections, he submits his little 
 work to the hands of those for whom it is intended. 
 
 Boston, Feb. 21, 1866. 
 
THE BOSTON MACHINIST. 
 
 1. Tlie Apprentice's first less* 
 The first thing for the Apprentice to learn 
 is: to clean and keep in order, the laf 
 planers, drills, milling and slabbing niacin: 
 This is done by brushing off the chips, 
 then wiping them with a wad of cotton 
 To clean a lathe, ran the carriage and pup 
 head about four feet from the main head, then 
 to keep the feed and gears dean, brush all the 
 chips towards the carriage, and after doing this, 
 wipe the head and wa\ in and oil tli 
 
 Then, after cleaning the carriage and puppet- 
 head, run them back to the main head, brush 
 the chips from the lower end of the lathe, wi] e 
 and oil the ways, and it is done. 
 
 2. Lesson second. 
 
 The next lesson is : to learn to trim cast- 
 ings. This is done by chipping off the rough 
 
10 
 
 THE BOSTON MACHINIST. 
 
 :' 
 
 m 
 
THE BOSTON MACIITNT 11 
 
 places with a cold chisel and then filling them 
 smooth with a second-hand file, which answers 
 quite as well as a new one. 
 
 3. Lesson third. 
 
 The next thing to learn is, to centre bolts, 
 shafts, etc. To do this, take a centre-punch 
 and hammer, and punch it into the centre of 
 each end of the shaft, or bolt as Dear the cen- 
 tre as you can guess ; then find a pail of l" i nch 
 centres and spring them apart, putting the 
 points into the punch-marks you have mad- 
 each end of the shaft. After doing this, take 
 a piece of chalk in one hand and turn the 
 shaft with the other, holding the chalk n 
 enough to the sh; ir the ends, to touch the 
 
 side that runs out. When yon have done this 
 take the shall from the I the 
 
 punch-mark towards the side marked by the 
 chalk. Continue these operations till the shaft 
 is true at the ends. 
 
 4. Lesson fourth. 
 
 Having learned to centre a shaft, you will 
 now proceed and learn to drill the centres. In 
 doing this, use a drill about one sixteenth of 
 
12 THE BOSTON MACHINIST. 
 
 an inch in diameter. Put the drill into a hand 
 lathe, and with one end of the shaft upon the 
 centre, drill the other, continually turning it 
 around while drilling. They should be drilled 
 about one fourth of an inch deep. After 
 doing this, countersink them with a three- 
 square countersink, made for the purpose. 
 
 5. Lesson fifth. 
 
 You will now learn other modes of drilling, 
 — the first being to drill holes through flat 
 pieces of iron. In doing this they are first 
 laid out a certain distance from the edges with 
 a pair of dividers. Then make a punch, mark 
 the distance from the edge or position where 
 you wish to drill the hole. After marking this 
 punch-mark, set your dividers the size you 
 want to drill the hole, and strike a circle 
 around the mark made by the punch. Having 
 done this, proceed to drill the hole, taking 
 great care to drill within the circle, and if your 
 drill runs to one side, chip a piece out of the 
 opposite side with a half round chisel, — this 
 will bring the drill back to the centre of the 
 circle. Continue this practice till the hole is 
 perfectly true, and if you are careful at the first 
 
THE BOSTON MACHINIST. 13 
 
 you will find no difficulty in drilling holes, and 
 drilling them properly. 
 
 6. To drill a large hole in 1 of a Shaft. 
 
 This is only done when you have no chuck 
 that will hold the shaft. To do it properly, 
 drill a small hole the depth required with a 
 straight spiral drill; or if you have none use a 
 fiat one that is straight on the sides ; then fol- 
 low with one or two more larger as may 
 be required. The object of using a small drill 
 first, is because being L re endwise on 
 the drill it will not run out side- 
 
 ild if the small hoi- i not drilled I 
 
 In drilling with small drills, such utre 
 
 drills, always speed up your drill 
 will run. This prevents the breaking drills, 
 and there is no danger of burning the points 
 off, as some suppose, except the steel be very 
 hard. 
 
 7. Straightening i hg. 
 
 Thi3 should be done by centring, as before 
 explained ; then put into a lathe, and the ends 
 squared up with what is called a side-tool. 
 After doing this, take a piece of chalk and try 
 
14 THE BOSTON MACHINIST. 
 
 it in several places, to find out where the worst 
 crooks are ; then, if you have not a machine 
 for springing shafting, spring it with a lever 
 where the worst crook is, and continue this 
 operation till the shaft is straight. 
 
 8. Setting a Lathe straight to turn Shafting. 
 
 First, see if your centres are true; if not, 
 turn them up. For this purpose a square-end 
 tool is best ; and they should always be kept 
 true to a three-square gauge. Unless you do 
 this, you will spoil about half your work, as 
 many a one has done. After this is done, set 
 your puppet-head so that it will turn the shaft 
 straight ; and if it has no straight mark upon 
 it, turn one end of the shaft for about an inch ; 
 then, without moving your tools, take the 
 shaft out of the lathe. Then run the carriage 
 down to the main head, put your shaft into 
 the lathe again, with the end which is turned 
 towards the main head, and if the tool touches 
 the place you have turned, the lathe is straight. 
 If it does not touch, screw over the puppet- 
 head, and keep trying it until your tool touches 
 the place turned, at either end of the 
 lathe. 
 
THE BOSTON MACHINIST. 15 
 
 9. Turning Shafting, 
 
 To do this properly, two chips should al- 
 ways be run over the shaft, for the reason that 
 it saves filing and leaves the shaft truer and 
 more round; and on shafts thus turned, the 
 time saved in filing more than compensates for 
 the time lost in turning. Before you com- 
 mence, you will put your feed-belts or gear on 
 a coarse feed. Turn off one a sixty-fourth of 
 an inch larger than the size required. Having 
 turned off this chip, commence the finishing- 
 chip, and turn it small enough to have the 
 pulley-wring on about an inch without filing. 
 This will leave it large enough to file and 
 finish. If there are couplings to go on a shaft, 
 with holes smaller than the holes in the pul- 
 leys, the ends of the shaft, where they fit on, 
 should be turned down to a sixty-fourth of an 
 inch of the size desired before any part of the 
 shaft is finished : that is, every part of a shaft 
 should be turned to within a sixty-fourth of an 
 inch of the size required, before any part of it 
 has the finish-chip taken off. The reason for 
 this is, that it leaves every part of the shaft 
 perfectly true, which would not be the case 
 
16 THE BOSTON MACHINIST. 
 
 were it done otherwise. Having done this, 
 you will file the shaft so that the pulleys will 
 slide on, and the couplings so that they will 
 drive on, polish the shaft with a pair of polish- 
 ing-clamps and some emery, and it is done. 
 
 10. Setting a Lathe to turn Tapering. 
 
 This is done by calculating the taper, a cer- 
 tain amount to the foot or length of the piece 
 to be turned. Therefore, if you have a shaft to 
 turn a foot long, with one end one inch larger 
 than the other, you will set your puppet-head 
 over one-half inch, and you will get the re- 
 quired taper of one inch to the foot. If you 
 have a shaft a foot long, and wish to turn one- 
 half of it tapering half an inch, you will set 
 the puppet-head over half an inch, as before ; 
 for the shafts being a foot long, you must cal- 
 culate your taper from the length of the shaft : 
 and if the taper is half an inch larger than six 
 inches from the end, and the shaft exactly a 
 foot long, the taper would be as before, one 
 inch to the foot. If you have a shaft to turn 
 that is twenty inches long, and you wish to 
 turn it tapering two inches in its whole length, 
 set your lathe over one inch, and this will give 
 
3. — A Right-hand Side Tool — side view. 
 4. — A Left-hand Side Tool — top view. 
 5. — A Round-ended Tool, for turning heavy shafting, 
 cast-iron, etc. 
 
 2* 
 
 facing: 
 
18 THE BOSTON MACHINIST. 
 
 you the taper required — two inches in twenty. 
 If you have a shaft twenty inches long, and 
 you wish to turn a taper half an inch in five, 
 set your puppet-head over one inch, as before ; 
 this will give you a taper of five inches in 
 twenty, and half an inch in five ; because half 
 an inch is one-fourth of two inches, and five 
 inches is one-fourth of twenty. If you have a 
 shaft twenty inches long, and want to turn it 
 taper one inch in ten, set your lathe over one 
 inch as before, and you have it ; for the shaft 
 being twenty inches long and two inches taper 
 in its whole length, it would be one inch only 
 in half its length. 
 
 11. Tools for different hinds of Turning. 
 
 1. The best tool for squaring up the end of 
 a shaft is what is called by machinists a side- 
 tool. The best tool for turning small shafting 
 is a diamond-point tool. 
 
 2. The best tool to turn heavy shafting is a 
 round-end tool, made to stand high like a dia- 
 mond point, and to cut freely from the 
 side. 
 
 3. The best tool to turn a balance-wheel of 
 cast-iron, or to square up any large surface, is 
 
ft. 
 
 7. 
 
 8. 
 
 6. — Top view of a Screw-Tool, for cutting Y threads. 
 
 7. — Side view of a tool for cutting Y threads. 
 
 8. — A diamond-point Tool, for turning small shafting. 
 
9. 
 
 10. 
 
 11. 
 
 9. — A Tool for cutting off a shaft ; is also used for cutting 
 
 square thread-screws. 
 10. — A Lath-boring tool. 
 11.— A Tool for cutting a Screw inside a hole. 
 
THE BOSTON MACHINIST. 21 
 
 also a round end tool, made well tapering to 
 cut from the side. 
 
 4. The best tool to cut off a shaft with is a 
 tool made thin and having the tapering 
 down, instead of up as in turning tools; this 
 generally prevents their running in and break- 
 ing. 
 
 5. The best tool to bore out a hole is a lathe- 
 boring tool with the end turned on a right 
 angle to the left and the point turned up hook- 
 ing. These tools bore far nicer than those 
 made square on the top. 
 
 6. The best tool with which to V 
 thread-screw, is a V thread-tool with the points 
 ground to lean down when finish, 
 
 vents running and breaking >ol, or tearing 
 
 the screw. 
 
 7. In cutting a square thread, first use a 
 square-point tool about three-fourths of the 
 thickness of the thread you design to cut, i 
 finish with one the size of the thread. The 
 same rule applies when cutting a thread within 
 a hole. 
 
12. — A Tool for planing a Key- Way. 
 
THE BOSTON MACHINIST. 23 
 
 12. Planer Tools. 
 
 The best tool for ordinary planing, is a half- 
 side tool made short, and with the point turn- 
 ed up, as an ordinary diamond point. 
 
 The best tool for squaring up, is a round- 
 point tool, cutting from the side. 
 
 The best tools for planing under, as in slide 
 rests, etc., etc., are sharpened up to a point, 
 with the point turned up, and with a taper from 
 the point to the body of about two inches. 
 
 13. Chucking Pulleys. 
 
 The term chuck, means to secure a piece of 
 work in a certain position, so as to drill, or 
 plane it true. The same name is given to the 
 instrument employed in holding the pieces of 
 w r ork. It is merely a round piece of iron, with 
 a hole in one side of it, within which is cut a 
 screw, for the purpose of securing it to the 
 spindle of a lathe. On the side opposite, is a 
 certain number of jaws, usually three or four, 
 which screw together for the purpose of hold- 
 ing a wheel, or other piece of work, while it is 
 being drilled. In chucking a wheel or pulley, 
 the first thing to be done, is to screw it into the 
 
24 THE BOSTON MACHINIST. 
 
 jaws of the chuck, as near the position desired 
 as you can guess. After doing this, screw a 
 tool into the post, and set one end of it near 
 the face of the pulley, then turn and adjust the 
 wheel by means of the screws, until the tool 
 touches it all round. After doing this, true 
 the edges in the same way. And then, try the 
 face again to see if it has moved. Some wheels 
 are cast oblong, by the pattern's shrinking; 
 and when wheels come this way, the proper 
 mode of chucking them, is to set your tool 
 against the face as before, turn and adjust the 
 wheel so that it will touch the tool at two oppo- 
 site points, then, with a rule, measure the two 
 points farthest from the tool, and adjust them 
 so they will be equal, and the wheel will be 
 true. Some mechanics use a piece of chalk, 
 but this is an improper way to true a wheel, 
 even when it is perfectly round, for a wheel 
 that is not chucked and drilled true, costs more 
 time in turning than is needed to chuck and 
 drill half a dozen wheels and pulleys, that are 
 perfectly drilled, for patterns should be trued 
 by the inside of the face and on the sides by 
 the arms. 
 
THE BOSTON MACHINE 
 
 14. Setting // resL 
 
 In doing- th it into the tool-post with 
 
 the middles of the slats through which the 
 drill passes, exactly as high as the centres of 
 your lathe, for if it is above or below the cen- 
 
 . it will cut the hole larger than the drill, 
 and thereby spoil the wheel. Havi the 
 
 . you can proceed to drill the wheel. r l 
 should be done with two drills, and where the 
 holes are cored badly out of true, even tl 
 should be used, it' you would 1. he hole 
 
 perfectly true, and the last drill should only 
 cut a chip one-sixteenth of an inch. This 
 leaves a good and true hoi 
 
 15. To drill a hole where y / 
 
 It is Bometimes n< rill a hole of 
 
 an exact size to fit a certain shaft, and at the 
 same time have it smooth without reaming it. 
 This may be done, by first drilling a hoi- 
 one-hundredth of an inch smaller than the size 
 desired, and then making a drill the size 
 
 and running it through to finish with. This 
 last drill should have the corners of its lips 
 rounded, like a reamer, and the hole should be 
 finished without holding the drill with a rest. 
 
26 THE BOSTON MACHINIST. 
 
 16. Boring a hole with a boring tool. 
 
 In boring a hole with a boring tool, it is 
 usually necessary to drill the hole first, and too 
 much care cannot be taken in finishing. An 
 iron gauge should be made first; is usually 
 made of a piece of sheet iron or wire. The 
 hole should then be drilled smaller than the 
 size desired, and then bored to the required 
 size, and it is impossible to bore a hole perfect 
 without taking two or three light chips, mere 
 scrapings, with which to finish. Holes, in this 
 way, may be bored as nicely as they can be 
 reamed. 
 
 17. Squaring^ or Facing up Cast Iron Surfaces. 
 
 A round-end tool is best for this. A rough 
 chip should first be taken off, over the entire 
 surface to be faced. Then speed your lathe up 
 and taking a light chip, merely enough to take 
 out the first tool-marks, run over the entire sur- 
 face again. In turning up surfaces it is always 
 best to begin at the centre and feed out, as the 
 tool cuts freer and will wear twice as long. 
 
THE BOSTON MACHINIST. 27 
 
 18. Scraping Cast Iron smooth. 
 
 To scrape cast iron, it is necessary to put a 
 rest close to the surface to be scraped, and 
 then with a thin wide scraper, commence by 
 resting your scraper on one edge and scraping, 
 twisting the scraper, and sustaining it while 
 cutting, in your hand. You must not bear on 
 hard, but scrape as light a chip as possible, and 
 yon will have no trouble in scraping cast 
 iron. 
 
 19. Keep your Lathe ck 
 
 I again remind you of keeping your lathe 
 clean, and your centres in siiai unless you 
 
 do this, you will soon spoil every arbor in the 
 shop; and the wuvs of your lathe will be torn 
 away, so as to be unfit to have any nice piece 
 of work done upon them. 
 
 20. Boring Holes with Boring Arbor. 
 A boring arbor is a shaft with a steel tool 
 in it, for the purpose of boring holes of great 
 length, and is designed to be used in a lathe. 
 In doing this properly, you must first see if 
 your lathe is set straight. If not, adjust it ; 
 
28 THE BOSTON MACHINIST. 
 
 having done this, put the piece of work to be 
 bored in the carriage of your lathe, pass your 
 arbor through the hole to be bored, and put it 
 on the centres of your lathe. Having done this, 
 adjust your work true to the position desired, 
 by measuring from the point of the tool, con- 
 tinually turning round the arbor from side to 
 side of the piece to be bored, while you are 
 bolting it to the carriage, and measure until it 
 is perfectly true. Having done this, bore the 
 hole, and take for the last chip only a hundredth 
 of an inch. This makes a true and smooth 
 hole. It is impossible to make a hole true with 
 any kind of a tool when you are cutting a large 
 chip, for the tool springs so that no dependence 
 can be placed upon it. 
 
 21. To make a Boring Arbor and Tool, that will 
 not Chatter. 
 
 Boring tools, when used in small arbors, are 
 always liable to chatter and make a rough 
 hole. To prevent this, the tool should be 
 turned in a lathe, while in its position in the 
 arbor, upon the circle of the size of the hole 
 to be bored, and the bearing lengthwise of the 
 arbor, should be only as wide as the feed of the 
 
THE BOSTON MACHINIST. 29 
 
 lathe; for if the bearing of the tool is on the 
 face, the more it will chatter. 
 
 22. Gearing a Lattiefor Screw-cutting. 
 
 Every screw-cutting lathe contains a long 
 screw called the lead screw, which feeds the 
 carriage of the lathe. While cutting screws, 
 upon the end of this screw is placed a gear, to 
 which is transmitted motion from another gear, 
 placed on the end of the spindle. These gears 
 each contain a different number of teeth, for 
 the purpose of cutting different threads, and 
 the threads are cut a certain number to the 
 inch, varying from one to fifty. Therefore to 
 find the proper gears to cut a certain number 
 of threads to the inch, you will first: — mul- 
 tiply the number of threads you desire to cut 
 to the inch, by any small number, four for in- 
 stance, and this will give you the proper g 
 to put on the lead screw. Then with the same 
 number, four, multiply the number of threads 
 to the inch in the lead screw, and this will give 
 you the proper gear to put on the spindle. 
 For example, if you want to cut twelve to the 
 inch, multiply twelve by four, and it will give 
 you forty-eight. Put this gear on the lead- 
 
 3* 
 
30 THE BOSTON MACHINIST. 
 
 screw, then, with the same number, four, mul- 
 tiply the number of threads to the inch in the 
 lead-screw. If it is five, for instance, it will 
 give you twenty. Put this on the spindle, and 
 your lathe is geared. If the lead-screw is four, 
 five, six, seven, or eight, the same rule holds 
 good. Always multiply the number of threads 
 to be cut, first. Some, indeed most small 
 lathes, are now made with a stud geared into 
 the spindle, which stud only runs half as fast 
 as the spindle, and in finding the gears for 
 these lathes, you will first multiply the number 
 of threads to be cut, as before, and then multi- 
 ply the number of threads on the lead-screw, 
 as double the number it is. For instance : if 
 you want to cut ten to the inch, multiply by 
 four, and you get forty. Put this on the lead- 
 screw, then, if your lead-screw is five to the 
 inch, you will call it ten, and multiply by four, 
 and it will give you forty. Again put this on 
 your stud, and your lathe is geared ready to 
 commence cutting. 
 
 23. Cutting a Screw in an Engine Lathe. 
 In cutting V thread-screw, it is only neces- 
 sary for you to practise operating the shipper, 
 
THE BOSTON MACHINIST. 31 
 
 and slide-screw handle of your lathe, before cut- 
 ting. After having done this, until you get 
 the motions, you may set the point of the tool 
 as high as the centre, and if you keep the tool 
 sharp, you will find no difficulty in cutting 
 screws. You must, however, cut very light 
 chips, mere scrapings, in finishing, and D 
 take it out of the lathe often, and look at it 
 from both sides, very carefully, to see that the 
 threads do not lean, like fish-scales. After cut- 
 ting, polish with an emery stick, and some 
 emery. 
 
 24. C'lft' 
 
 In cutting square thread* 
 necessary to get the depth required, with a tool 
 somewhat thinner than one-half the pitch of 
 the thiv After doing this, make another 
 
 tool exactly one-half the pitch of the thr 
 and use it to finish with, cutting a light chip on 
 each side of the groove. After doing this, pol- 
 ish with a pine stick, and some emery. 
 Square threads, for strength, should be cut one- 
 half the depth of their pitch, while square 
 threads, for wear, may, and should be cut 
 three-fourths the depth of their pitch. 
 
32 THE BOSTON MACHINIST. 
 
 25. Mongrel Threads. 
 Mongrel, or half-V, half-square threads, are 
 usually made for great wear, and should be cut 
 the depth of their pitch, and for extraordinary 
 wear, they may even be cut one and a half the 
 depth of their pitch. The point and bottom 
 of the grooves should be in width one-fourth 
 the depth of their pitch. What is meant here by 
 the point of the thread, is the outside surface. 
 And the bottom of the groove is the groove 
 between the threads. In cutting these threads 
 it is necessary to use a tool about the shape of 
 the thread, and in thickness about one-fifth, less 
 than the thread is when finished. As it is im- 
 possible to cut the whole surface at once, you 
 will cut in depth about one-sixteenth at a time, 
 then a chip off the sides of the thread, and 
 continue in this way, alternately, till you have 
 arrived at the depth required. Make a gauge 
 of the size required between the threads, and 
 finish by scraping with water. It is usually 
 best to leave such screws as these a little large 
 until after they are cut, and then turn off a 
 light chip, to size them. This leaves them true 
 and nice. 
 
TBI DO01 LCHINIf 33 
 
 26. P 
 
 Ti tion in planii ) oil your 
 
 planer and find out if the b -mooth. If it 
 
 is not, file off the rough p] Then chs 
 
 the they work well, and find out 
 
 iments of the plan* After doing 
 this, bolt your work on to the md if it is 
 
 a long thin piece, plane off a chip, then I 
 
 r and finish the oth< airing two 
 
 chips, the last of which Id be very lij 
 
 at care should be taken, in boltii i the 
 
 . not to spring it. 
 turn it to the otl and take off a I 
 
 cut to finish it. 
 
 27. P rly. 
 
 In planing perpendicularly, it is n< y to 
 
 swivel the bottom of the small head around, so 
 it will stand about three-fourths of an inch in- 
 side of squar ards the piece you an 
 plane. This prevents breaking the tool when 
 the bed runs back. 
 
 28. Planing a Key- Way. 
 To place a key-way in a shaft, it is necessary 
 to first drill a hole, the size you intend to 
 
34 THE BOSTON MACHINIST. 
 
 make the key-way, as deep as you want to 
 plane. Then with a square point tool, plane 
 the key- way a little narrower than you design 
 to finish it down to the proper depth. After 
 doing this, finish with a tool of the desired 
 size. Some think it unnecessary to use two 
 tools to plane a key-way, and argue that it takes 
 more time. This may be the case, but it is 
 impossible to plane a key-way with one tool, 
 especially a narrow one, without tearing it, and 
 again it is impossible to tell whether or not 
 the tool will run under sidewise until you 
 have planed the way its depth. Therefore if 
 you first plane the way with a narrow tool, and 
 it is found to run under, it is very easy to set it 
 right in cutting out the finish chip. In setting 
 a tool to cut a key-way, set a square on the 
 planer-bed, and try both sides of it near the 
 point, to see that it is perpendicular. This 
 will usually prevent its running under. 
 
 29. Planing a T-shaped Slat. 
 
 In planing a T-shaped slat, or way, such as 
 are used for slides, or on a planer bed, to hold 
 the head of a bolt, it is first necessary to plane 
 to the desired depth, with a square point tool, 
 
Till; BOSTON MACHINIST. 35 
 
 and after doing this, plane the upper part of 
 the way to the desired width. Having done 
 this, plane the bottom part of the way with 
 two tools, one bent on a right angle, and the 
 other to the left. And in planing large w 
 these tools should be made as small as they will 
 Stand without breaking, and should cut freely 
 on each of the three sides. Make a sheet iron 
 gauge, and plane the way to it. In small shal- 
 low ways they may be planed the depth and 
 upper width at once, and then finished with 
 one tool, made the desired shape of th 
 This saves time. 
 
 30. To Plane a Rest or Si 
 
 Plane it all o\ I the slide, first on 
 
 both Bides, then setting the planer head on an 
 
 angle of thirty degrees, finish the slide with a 
 taper point tool. 
 
 31. Note. 
 
 In planing metals, especially thin east iron 
 surfaces, it is always necessary to plane over a 
 cut on both sides, before finishing, either for 
 the outside or scales. Being harder than the 
 inside, the moment the scale is taken off the 
 
36 THE BOSTON MACHINIST. 
 
 piece springs through the expansion of the 
 scale on the opposite side. Hence the neces- 
 sity of planing both sides before finishing 
 either. 
 
 32. Gear Cutting. 
 
 In cutting gears, they are reckoned a certain 
 number of teeth to the inch, measuring across 
 the diameter to a certain line which is marked 
 on the face or sides of the gear with a tool. 
 This line is one half the depth of the teeth 
 from the outer diameter. That is, if the teeth 
 of the gear are two-tenths of an inch deep, this 
 line would be one-tenth of an inch from the 
 edge, and is called the pitch line. 
 
 33. Depth of Teeth. 
 
 Every gear cut with a different number of 
 teeth to the inch, should be cut of a depth to 
 the pitch line, to correspond with the number 
 of teeth to the inch. This is called proportion. 
 Therefore, if you cut a gear eight to the inch r 
 the depth to the pitch line should be one-eighth 
 of an inch, and the whole depth of the tooth 
 would be two-eighths. Again, if you cut a 
 gear twelve to the inch, the depth to pitch line 
 
TIIK BOSTON MACHINIST. 37 
 
 ihould be one-twelfth of an inch, and the 
 whole depth of tooth two-twelfths. A .an, 
 
 if you cut a gear twenty to the inch, the depth 
 to pitch line should be one-twentieth of an inch, 
 while the whole depth should be two-twentie* 
 and so on, ad infinitum. 
 
 c)4. M to find tfu A 'h. 
 
 To find the size a certain for 
 
 a certain number of teeth, is ao I r if 
 
 you study carefully these ru]. you v. 
 
 a gear with thirty-two teeth and to the 
 
 inch, it should g across 
 
 the diameter to the pitch 1. I the two- 
 
 itlis on itch line would mak 
 
 four ii: od two-eighths, 
 
 want a gear with iort; ., and ten to the 
 
 inch, it ild m< the diam< 
 
 to pitch line lour inches, and the Qthfl 
 
 outside the pitch line would make the whole 
 diameter four inches and t. And 
 
 nn, if you want a gear with eighty teeth. . 
 twenty to the inch, it should measure to the 
 pitch line, across the diameter, four i . and 
 
 the two-twentieths outside the pitch line would 
 make it four inches and two-twentieths, and 
 
 4 
 
38 THE BOSTON MACHINIST. 
 
 these examples will form a rule for the mea- 
 surement of all except bevel gears. 
 
 35. Bevel Gears. 
 
 These are turned a certain bevel to corre- 
 spond with each other, according to the angle 
 upon which the shafts driven by them are set. 
 For instance, if two shafts are set upon an angle 
 of ninety degrees, the surfaces of the faces of 
 these gears will stand at an angle of forty-five 
 degrees. To get the surface of these gears, in 
 turning them, puts a straight edge across the 
 face. Then set your level on an. angle of forty- 
 five degrees, and try the face of the teeth by 
 placing the level on the straight edge. After 
 turning the face of the teeth, square the outer 
 diameter by the face of the teeth ; and to get 
 the size to which you wish to cut, measure 
 from the centre of the face of the teeth. Thus, 
 if a bevel gear is six inches in diameter, and the 
 face of the teeth is one inch, you will measure 
 from the centre of the face, and find it is five 
 inches. On this line you calculate the number 
 of teeth to the inch, and if you want a gear 
 with twenty teeth, and ten to the inch, it should 
 measure two inches across the face to the centre 
 
THE BOSTON MACHINE 39 
 
 of the surface of the teeth ; and if the face of 
 teeth were one inch in length, the diameter 
 of the gear would be three inches, and the 
 •jf the teeth would measure only one 
 inch. Again, if you want to cut a gear with 
 forty teeth, and ten to the inch, it would mea- 
 sure four inches to the centre of the teeth on 
 And if tl :ace of th 
 
 inch long, the diameter of the g 
 would be five inches, while it would oni 
 sure three inches inside the teeth. These 
 amplaa will form a rule for all rs. 
 
 36. 7 Styles of 1 
 
 To file a surfac it is n v on com- 
 
 mercing, to - • the file tightly 1 
 
 ir third and fourth li and the palm of 
 
 your hands, until you become used to it. Your 
 position in filing should be half I » to 
 
 your work, with the middle of your foot 
 
 fifteen inches behind vour left heel ; and to file 
 your work true or square, it is d j to 
 
 reverse your work often, as by this means you 
 are enabled to see the whole surface you are 
 filing, and to see, while filing, whether you are 
 filing true or not. Where, however, your 
 
40 THE BOSTON MACHINIST. 
 
 work is so heavy that you cannot reverse it, 
 you had better file first to the right, and then 
 to the left, as by this means you can plainly 
 see the file marks, and this again assists you in 
 filing true. 
 
 37. To File a Square Hole. 
 
 To file a hole square, it is necessary to reverse 
 the work very often. A square file should first 
 be used, and the holes finished with either a 
 diamond-shaped file, or a half-round one. This 
 leaves the corners square, as they properly 
 should be. 
 
 38. Draw-Filing and Finishing. 
 
 To draw-file a piece of work smoothly and 
 quickly, it is best to first draw-file it with a 
 medium fine file, and finish with a superfine 
 file. After doing this, polish the work with 
 dry emery paper, and then with emery paper 
 and oil. 
 
 39. Lining Boxes with Babbitt Metal. 
 
 To line boxes properly, so as to insure their 
 filling every time, it is necessary to heat the 
 box nearly red hot, or at least hot enough to 
 
Tin: BOSTON MACHINE 41 
 
 melt the metal. Then smoke the shaft where 
 metal is to be poured upon it. This insures 
 its coming out of the 
 
 cold. After smoking the shaft, put it into the 
 box or boxes, and draw so: tty around the 
 
 ends of them, for the purpose ing 
 
 them, taking eare not to | upon it, for if 
 
 you do it will go into the id fill a place 
 
 that ought to be filled with Dl< nd in the 
 
 iiitime your metal ought to I 
 after you have poured it, let the ind till 
 
 it is nearly cold; dri it your shaft, 
 
 is done. 
 
 40. Making L 
 
 Melt in a crucible, one and a half | - of 
 
 copper, and while the i is in. It:: 
 
 in a ladle twenty-live pounds of tin, and three 
 
 of antimony, Dearly red hot P<»ur the I 
 
 together, and stir until nearly cool. This 
 
 makes the finest kinds of lining metal. 
 
 • 
 41. Putti,, ^gdher. 
 
 In putting machines together, no part should 
 be finished except where it is i. :y to make 
 
 a fit, as it is sometimes the case that machinery 
 
42 THE BOSTON MACHINIST. 
 
 is miscalculated, and by finishing, it would be 
 spoiled, while if it were not, it might be saved 
 by slight alterations in design. And again, in 
 finishing certain parts before you get a machine 
 together, you are unknowingly finishing parts 
 not necessary to be finished, and making them 
 of a shape anything but desirable. This rule, 
 however, is not intended to apply to machinery 
 being made to detail drawings. 
 
 42. Worhing Steel for Tools. 
 
 In working steel for tools, great care should 
 be taken to hammer ail sides alike, for if one 
 side is hammered more than another, it will 
 cause it to spring in hardening. Again, steel, 
 when being hammered, should be heated as hot 
 as it will stand, until finishing, and should 
 then be hammered until almost black hot, for the 
 reason that it sets the grain of the steel finer, and 
 gives the tool a better edge. The reason for 
 heating the steel so hot while hammering, is 
 simply because it makes the steel tougher when 
 hardened, and softer when annealed ; while if 
 it were worked at a low red heat, the continued 
 percussive shocks of the hammer w T ould so har- 
 den it as to make it almost impossible to anneal 
 
TIIK BOSTON MACHINIST. 43 
 
 it, and at the same time render it brittle when 
 hardened. 
 
 43. Anneah d. 
 
 Tn annealing steel, it should be heated as 
 slowly as possible to a red 1; at, but never hot 
 enoi - scale, and Bhould then have two 
 
 days or more " to cool in." Apiece of steel 
 that is heated hot enough to SC r be 
 
 annealed well, without working over, and is 
 always rendered glassy, and bad to work, 
 prove this, take a steel shaft and beat it in 
 several places, hot enou 
 
 ral oth Allow it to cool, 
 
 and when you turn it, you will see at once 
 that the places 1. | enough t<> . are 
 
 considerably harder than t!. ated properly. 
 
 All tools that are required t<> be hardened with- 
 out springing. itters and reamers, should 
 be turned to exactly one- fourth of an inch of 
 their size, and then annealed before finishing. 
 This takes the strains out, so that when they 
 are heated for the purpose of hardening, they 
 will not spring. 
 
41 THE BOSTON MACHINIST. 
 
 44. Water Annealing. 
 
 Heat the steel to a red heat, and let it lie a 
 few minutes, until nearly black hot, then throw 
 it into soap-suds. Steel, in this way, may be 
 annealed softer than by putting it in the ashes 
 on the forge. 
 
 45. Hardening Steel Tools of the various Kinds. 
 
 All steel tools should be hardened at a low 
 red heat, or the lowest heat at which they will 
 harden, and the larger a piece of steel is, the 
 greater the heat required to harden it. This is 
 on account of its taking longer to cool, for the 
 moment a large body of heated steel is plunged 
 into the water, the steam arising from the sur- 
 face of the steel blows the water away from it, 
 and thereby causes it to take more time in 
 cooling. For instance, an anvil heated red-hot 
 and thrown into a hogshead of water, would, 
 instead of hardening, blow the water away 
 from it and cool slowly, until the water boiled, 
 and when taken out, would be as soft as before 
 it was put in. Hence the necessity of harden- 
 ing anvils under a jet of water, or a waterfall. 
 Very small tools, as needles and centre-drills, 
 
THE BOSTON MACHINIST. 45 
 
 penknives arid lancet-blades, should be harden- 
 ed in oil, or in water slightly wan. by 
 cooling in cold water, they cool too quid, 
 and are either rendered brittle, or cracked, 
 as to be worthless. This is also the case in 
 hardening springs — they are almost invariably 
 broken, when hardened in cold water, and 
 therefore should be hardened in oil. I have a 
 razor which, being too soft, I hardened in oil — 
 after being concaved — without springing in 
 the least, and it is now as good a I as I 
 ever us«d. A piece of steel for a tool of any 
 kind should never be 1 hot i h to 
 raise Bcalea on ii pt where it is bo lai 
 
 that it will not harden without ; j , when 
 
 hardened at that heat, le in 
 
 grain, and brittle, and you may draw the tem- 
 per of it to a straw i nd it will still break 
 more easily than a piece hardened at a 1 
 heat, and not drawn at all, and at th 
 time the piece that is heated hot enough to 
 scale, and drawn, will be softer than the piece 
 hardened properly. Hence it is necessary to 
 take great care, in hardening steel for tools. 
 
boston mac: 
 
 46. Dipping tools when hardening. 
 
 To harden a penknife blade, lancet, razor, 
 chisel, gouge-bit, plane, spoke-shave, iron-shav- 
 ing knife, three and four-square files, and round 
 and flat files, dip them endwise or perpendicu- 
 larly. This keeps them straight, which 
 would not be the case were they dipped, or 
 put into the water otherwise. 
 
 
 47. Dipping a half-round file or reamer, 
 
 To dip a half-round file, or any tool that is 
 solid, half-round, dip it with the half-round side 
 twenty degrees leaning towards the water. 
 This hardens it nearly straight. It is necessary 
 here to remark that the surface of any piece of 
 steel that is half round, has half as much 
 again surface on the half round side to be 
 hardened, as the flat side has, and the contrac- 
 tion of the steel being equal, according to the 
 surface, the necessity of dipping the half-round 
 side at an angle, is apparent. That is a half- 
 round surface tending to one point, which is, or 
 has one and a half, the surface or power of con- 
 traction, as the flat side. This contraction is 
 what draws a piece of steel to one side, and 
 makes it crooked. 
 
THE BOSTON" MACHINIST. 47 
 
 48. Dipping a ftui ner property. 
 
 Dip it perpendicularly to a short distance 
 beyond the fluting — that is to bout half 
 
 an inch, and withdraw and return it several 
 times. This hardens all the lips, and prevents 
 its cracking off at the water's edge, which is the 
 case when a piece of steel is dipped in to a cer- 
 tain depth, and allowed to cool without mov- 
 ing. Arbors or mandrels are often broken off 
 at the ends in this way, without the workman's 
 knowing what caused them to era 
 
 49. /" ' tools. 
 
 Drawing the temper of tools, is usually done 
 in a charcoal flame, and to draw the temper of 
 a tool properly, it should be held in the thick- 
 est part, or the part not requiring any t 
 towards the lire, and in the meantime, should 
 be often wiped with a piece of waste or a i 
 dipped in oil. The oil the temper even, 
 
 and prevents its drawing more in one place 
 than another. And in drawing the temper of 
 any tool it should be drawn very slowly, — 
 otherwise it will run too for ere you are aware 
 of it. Lancet-blades and razors should be 
 drawn to a straw color. Knife-blades and 
 
48 THE BOSTON MACHINIST. 
 
 
 chisels should be drawn to a copper or almost 
 red color. Plane irons, shaving knives, and 
 shoemakers' knives the same temper. Cold 
 chisels and stone drills should be drawn to a 
 dark blue. Fluted reamers should only be 
 drawn to a straw color, on the end, as they 
 never break elsewhere, and keep their size 
 longer by leaving the lips hard. Half round 
 or tapering reamers, also taps, dies, and drills, 
 should be drawn to a straw color. Jijucs and 
 gauges, also common lathe tools, need no draw- 
 ing, being tempered enough when merely hard- 
 ened. 
 
 50. Fancy tool making. 
 
 Probably no profession among the fine arts 
 is more " scientific," or requires greater care, 
 than the art of gun, and watch, or fancy tool 
 making, and it is safe to say, that not one 
 machinist in five hundred will make a good 
 tool maker. We will now commence on — 
 
 51. Malting collets, or drill sockets. 
 
 The best collets for drill lathes are those 
 which screw on to the spindle, and provided 
 with a tapering hole, for the shank of the drill 
 and a key-way, to. hold the end of the drill 
 
THE BOSTON MACHINIST. 49 
 
 from turning. These collets are always true, 
 and you have not the trouble bra .our 
 
 drill whenever you use it, as with others. 
 Collets for ordinary job shape, should be m 
 with a set screw to hold the drills, and the I 
 for the drill shank should be drilled to fit 
 round drill steel, about seven- iths of an 
 
 inch in diameter. This saves fitting the shanks 
 of drills, and these drills are quit.,' asgoo« : 
 drills made of forged steel. 
 
 52. To maize a c rJy. 
 
 For such collets as screw on to the drill lat I 
 bore out the end and cut the fit the 
 
 spindle well, and when you have done I 
 
 screw it on the lathe v. 
 
 After (loin drill a lid.' for the drill-shank 
 
 about an inch and a quarter d iking care 
 
 to drill it perfectly true, then ream i' 
 
 Having done this, cut a key-way through the 
 
 solid metal, below the bottom of, and running 
 
 into the hole drilled for the shank. Th 
 
 way should be half an inch long, and a fourth 
 
 wide. It is intended to hold the drill, the end 
 
 of which is filed flat. 
 
 5 
 
50 THE BOSTON MACHINIST. 
 
 53. To make a collet for upright drills. 
 
 Drill the centres, and turn up the end to be 
 drilled for the shank, so it will run in a back 
 rest, and after doing this, put the end to be 
 drilled into the back rest and the other end on the 
 centre of your lathe, and drill the hole for the 
 shank. When you have done this, take it out 
 of the back rest, and using the hole for a cen- 
 tre, turn it to fit the drill, put a set screw in it, 
 and it is done. 
 
 54. Making drills. 
 
 There are numerous styles of drills. Every 
 drill should be made straight on the sides of 
 the lips, for at least half an inch from the end 
 This prevents their running under or to on 
 side. To this rule, however, we will except 
 very small drills, as they would, if made in this 
 way, soon get broken by the small particles of 
 iron dust that force their way between the sides 
 of the drill, and the sides of the hole being 
 drilled. 
 
 55. Spiral drills. 
 
 To make a spiral drill, anneal it and turn it 
 one-fiftieth of an inch larger than you intend it 
 
 • 
 
52 THE BOSTON MACHINIST. 
 
 to be, when finished. Then heat it again, and 
 anneal it in a perpendicular position, either by 
 putting it into lime or ashes in an upright po- 
 sition, or dipping it into soap-suds. After 
 doing this, turn the shank to fit a certain col- 
 let socket or chuck (the names are various in 
 different shops), and after doing this, you may 
 turn the point or end to the desired shape and 
 size. Then measuring from that point, turn it 
 tapering, one-hundredth of an inch smaller, for 
 every two inches of the drill's length, and the 
 turning part is done.* 
 
 * The reason for again heating a piece of steel after par- 
 tially turning it, is simply because it is often hammered 
 harder on one side than the other, and the turning it true, 
 frequently takes more stock on one side than the side oppo- 
 site. This leaves the side from which the lightest chip is 
 taken much harder than the other, and this is the principal 
 cause of a reamer or other slender tool's springing when it 
 is hardened. Again, annealing tools in a perpendicular 
 position is better than to lay them on their sides, for the rea- 
 son that they sometimes he with their weight at each end, 
 and this will always spring a reamer, or other slender tool. 
 Almost everyone has seen a board lie with its weight 
 resting upon its two ends, and that its own weight caused 
 it to settle in the middle. Upon this principle, a piece of 
 steel will settle when annealing, if not placed in a proper 
 position. But if dipped into the water perpendicularly, the 
 result will be, that when it is hardened, it will spring or 
 strain itself to its proper position. 
 
THE BOSTON MACHLNJ 53 
 
 56. Catting the Spiral < < •?. 
 This is done in a machine made for the pur- 
 pose, which contains a spindle, which revo! 
 slowly while the grooves are being cut. This 
 spindle also slides slowly, while grooves are 
 being cut, and contains a screw, upon the 
 of which is fastened a chuck, for holding the 
 drill. You will put your drill into this chuck, 
 and raise the sliding block which La beneath 
 drill, until it touches the drill, takin not 
 
 to raise it too high, so that the drill shall 
 raised above the centre of the chuck into which 
 it is screwed. Having adjusted your machine, 
 you will put in a cutter, and groove your drills 
 as follows: for drills one eighth of an inch in 
 diameter, cut them two to the inch, calculal 
 as you would in cutting a 8C1 i an engine 
 
 lathe, and the depth of the groo >uld be 
 
 cut to within one hundredth of an inch of the 
 centre of the drills. For drills one half an i 
 in diameter, one and a half to the inch, 
 down to within a sixty-fourth of tl litre. 
 
 Drills one inch in diameter, should be cut one 
 to the inch, and down to a thirty-second of the 
 centre. The index plate will give you the two op- 
 posite points from which to commence cutting. 
 
 5* 
 
54 THE BOSTON MACHINIST. 
 
 The thickness of the cutter should be one 
 half the diameter of the drill, and the edge of 
 the cutter or teeth should be rounded to a per- 
 fect circle. 
 
 57. Flat Drills for Chucking. 
 Such drills should be made of three lengths 
 only. That is : when a lot is made for a shop, 
 all sizes of three-fourths of an inch and above, 
 should be made fifteen inches long. All sizes 
 from three-fourths, down to three-eighths of an 
 inch, ten inches, and sizes below that, five 
 inches long. This saves the time usually lost 
 in moving your puppet, when drilling your 
 hole with several differently sized drills. As 
 these drills are made to be followed by certain 
 sized reamers, they should be made exactly 
 one hundredth of an inch, at their ends, smaller 
 than the reamer designed to follow them, and 
 should be tapering, so as to measure, at a dis- 
 tance of three inches from the points, one hun- 
 dredth of an inch smaller than at the point. 
 Eun this taper to the centre. Draw-file the edges, 
 the same shape as turned by the lathe. Such 
 drills should never have their edges filed square, 
 as they are made in some country shops, for it 
 is impossible to drill two holes of a size, with 
 
 
THE BOSTON MACHINIST. 55 
 
 drills made in this way. The more nearly 
 square such drills are made on their ends, the 
 longer they will wear. It is necessary, how- 
 ever, to take off the corners. In hardening 
 such drills, it is not necessary to draw the tem- 
 per, as they never break, and it is my philoso- 
 phy never to draw the temper of a tool tli 
 not liable to break, for the harder they are, the 
 longer they will wear. 
 
 58 Tap and Reamer Wrenches, 
 
 Tap and reamer wrenches should be made 
 square in the middle, and should have a square 
 hole punched, or cut, through the square, to 
 hold the head of the tap, or reamer, while 
 the ends should be turned round, to within 
 half an inch of the hole in the middle. 
 
 59. Proportions for Tap and Reamer Wr 
 
 Very small taps should be used in file 
 handles. Wrenches for taps, and real 
 one-eighth of an inch to five-sixteenths, should 
 be five inches long, with a square in the mid- 
 dle half an inch in diameter, and a square hole 
 cut through it, three-sixteenths in diamel 
 The ends are to be turned rounding, half an 
 inch at extreme ends, and five-sixteenths near 
 
56 THE BOSTON MACHINIST. 
 
 the hole in the middle. The extreme ends 
 should be rounded with a hand tool and polish- 
 ed, so as not to hurt the hands of the user. 
 
 60. Tap and Reamer Wrenches, Size two. 
 "Wrenches for taps, and reamers, from five- 
 sixteenths to seven-sixteenths, should be ten 
 inches long, with a square in their middle five- 
 eighths in diameter, and a square hole through 
 square, five-sixteenths diameter. Ends round, 
 five-eighths by seven-sixteenths. 
 
 61. Tap and Reamer Wrenches, Size three. 
 
 Wrenches for taps and reamers, from seven- 
 sixteenths to five-eighths, should be fifteen 
 inches long. Square in middle, seven-eighths. 
 Hole through square, seven-sixteenths. Ends 
 turned rounding, three-fourths by nine-six- 
 teenths. 
 
 62. Wrenches for Taps and Reamers, Size four. 
 Wrenches for taps and reamers, from five- 
 eighths to thirteen-sixteenths, should be twenty- 
 four inches long. Square in middle, seven- 
 eighths by one and one-eighth inches. Hole 
 through largest way five-eighths. Square ends, 
 turned seven-eighths by eleven-sixteenths. 
 
 
THE BOSTON MACHI 
 
 17.— A V-Tli' t-w. 18.— A Screw for gr .gth. 
 
 19.— A Square Thread Screw. 
 
58 THE BOSTON MACHINIST. 
 
 63. Wrenches for Taps and Reamers, Size five. 
 
 Wrenches for taps and reamers, from thir- 
 teen-sixteenths to one inch, thirty inches long. 
 Square in middle, seven-eighths by one and 
 three-eighths. Hole in square, thirteen-six- 
 teenths. Ends, round, seven-eighths by three- 
 fourths. 
 
 64. Wrenches for Taps and Reamers, Size six. 
 
 Wrenches for taps and reamers, from one 
 inch to one and a fourth, forty inches long. 
 Square in middle, one inch and five-eighths by 
 one inch. Hole through square, one inch. 
 Ends turned, one inch by seven-eighths. 
 
 65. Making Taps. The Turning. 
 
 This is a process requiring care, and every tap 
 should have immediately under its head, or 
 square for the wrench, a place turned exactly 
 the size of the outside of the thread. You have 
 then no trouble in getting the size of the 
 threads, when they have an odd number of 
 flutes in them. Every tap should also be 
 exactly the size of the bottom of the thread, 
 from the termination of the thread, which is 
 usually about middling, to within about half an 
 
THK BOSTON MACHINIST. 59 
 
 inch of the head, or square. This you will 
 leav get the size of the outside of the 
 
 thread, as aforesaid. It is a foolish error in 
 tool makers, to make a iff above the 
 
 termination of the thread, for the reason, that 
 when in tapping a hole you come to a sudden 
 
 >, the tap is sure to break; when, if it f 
 turned straight from the terminus of the thr 
 nearly up to the head, it would tw 
 of break i 1 
 
 66. P 
 
 The sizes mark half an inch, in I 
 
 echedul in proportion to tk h of 
 
 the an- mostly used wit 
 
 screw-driver. I think them fully 
 threaded enough for all purp I im- 
 
 bers marked coarser tli, n to the inch, are 
 
 calculated for square-thi 
 Screws of one-sixteenth indiameti j to 
 
 the ineh. 
 
 Screws of one-eighth in dial forty 
 
 threads to the inch. 
 
 Screws of three-sixteenths in diameter, thirty 
 to the inch. 
 
 Screws of one-fourth in diameter, twenty -five 
 to the inch. 
 
60 THE BOSTON MACHINIST. 
 
 Screws of five-sixteenths in diameter, twenty 
 to the inch. 
 
 Screws of three-eighths in diameter, seven- 
 teen to the inch. 
 
 Screws of seven-sixteenths in diameter, four- 
 teen to the inch. 
 
 Screws of half an inch in diameter, twelve to 
 the inch. 
 
 Screws nine-sixteenths in diameter, twelve 
 to the inch. 
 
 Screws five-eighths in diameter, eleven to 
 the inch. 
 
 Screws eleven-sixteenths in diameter, eleven 
 to the inch. 
 
 Screws three-fourths in diameter, ten to the 
 inch. 
 
 Screws thirteen-sixteenths in diameter, ten to 
 the inch. i 
 
 Screws seven-eighths in diameter, nine to 
 the inch. 
 
 Screws fifteen-sixteenths in diameter, nine to 
 the inch. 
 
 Screws one inch in diameter, eight to the inch. 
 
 Screws one inch and one-sixteenth diameter, 
 eight to the inch. 
 
 Screws from one and one-eighth to one and 
 one-fourth in diameter, seven to the inch. 
 
THE BOB] L0H1NI8T. 61 
 
 Screws from one and one-eighth to one and 
 One-fourth of an inch in diarn< the 
 
 inch. 
 
 ■ s from one and five to one and seven- 
 sixteenths in diameter, six threads to the inch. 
 
 Screws from one and a half to one ; 
 eleven-sixteenths in diameter, five thn 
 the inch. 
 
 Screws from one and three-fourths to I 
 inches in diameter, four threads to the inch. 
 
 67. Outti I 
 
 V-thread taps should I with a 
 
 exactly three-square. Some contend that they 
 should lepth <>f their pi it I 
 
 consider ti [uare tl 
 
 n the I 
 
 They should he finished with a shan 
 the threads should never be polished in the 
 threads, as the polish produc the 
 
 iron, or steel, while tapping, — which would 
 be the case, were it left rough. In cuttii 
 tap for ordinary machine screws, or 
 should measure with a pair of sharp callij 
 the bottom of the thread of one of the scr« 
 and cut your tap at the bottom of the thread, 
 the same size. As the sizes of the scr 
 
 6 
 
62 
 
 THE BOSTON MACHINIST. 
 
 \.S\rS' 
 
 <M 
 
 20. — Side view of a Square Thread-Tap. 
 
THE BOSTON MACHINES 
 
 are so irregular, this is the B ray to get 
 
 a fit. 
 
 68. Square Thread-screws. 
 
 Taps for square threads* -igned for 
 
 strength, should be cut one-half the depth of 
 their pitch. Therefore, if your thread is five 
 to the inch, you will cut it one-tenth of an inch 
 deep. Your threads being five to the inch, 
 there would be a space between the threads one- 
 tenth of an inch, and the thread being one- 
 tenth wide, and one-tenth d \ ould form the 
 square thread. Square tin r, how- 
 ever, should be cut three-fourths tli b of 
 their pitch. 
 
 69. Mongrel^ or half ]" half square Threa 
 
 These threads, made for gnat wear, are diffi- 
 cult to cut. They should be cut the depth of 
 their pitch, and for extra great wear, where a 
 
 screw is required to be kept accurate for a l< 
 time — such as the lead screw for a lathe, — they 
 should be cut one and a half the depth of their 
 pitch. The outside of the thread, also the bot- 
 tom of the thread, should be in width, one- 
 fourth of the thread's pitch. Therefore, if you 
 were cutting a screw, five to the inch, it should 
 
64 THE BOSTON MACHINIST. 
 
 be one-twentieth in width on the outside, and 
 one-twentieth at the bottom of the thread. 
 
 70. Fluting Taps. 
 
 Every tap should be fluted with the teeth a 
 little hooking on the face. That is, in strik- 
 ing a line through the middle of the tap, on 
 the end, the flute or groove should be inside 
 that line, while the flute at the outside of the 
 thread is exactly on the line. The back side of 
 the teeth, however, may lean a little outside of 
 the centre, but not enough to allow the dust to 
 ride over, when backing out the tap. It is 
 needless to say that it is impossible, in steel, to 
 cut a coarse thread full with a tap, that has the 
 faces of its teeth leaning backwards, without 
 tearing out half the threads, for taps, made with 
 the faces leaning backwards, do not cut, they 
 merely stretch and tear the thread to its size, 
 instead of cutting it. It is, in fact, upon the 
 principle of turning a shaft with a square end 
 tool, with the point or end leaning downwards. 
 
 71. How to go to ivorlc. 
 Set your tap on the centres, and with a cut- 
 ter or planing tools made round at the end, and 
 the thickness of the end one-fourth the diame- 
 
THE BOSTON MACHINIST. 65 
 
 tcr of the tap. Plane the faces of all the teeth, 
 one-half the depth of the thread below the bot- 
 tom of the thread. For instance, if a thread is 
 an eighth of an inch deep, plane or mill it one- 
 sixteenth below the bottom of the thr< 
 After planing all the faces, or milling them all 
 to their depth, plane or mill off the back sides 
 of the teeth, leaving them one and a half the 
 breadth of their pitch. Thus, if the pitch is 
 ten, leave them a tenth, and a twentieth. T 
 leaves fully stock enough for strength, and the 
 less bearing a tap has, the more easily it tu 
 The back sides of the teeth should be i 
 with a cutter, or planing tool, made in thick 
 of the size of the tap. It is economical to 1 
 two taps for every thread, and have the I 
 one small enough to cut only two-thirds of the 
 thread, and the second to finish. Taps, for 
 five threads, made in this way, need no taper. 
 They never go hard, and do not get broken, 
 half so often, as when they are both of a E 
 Very large mongrel thread taps should alw 
 be of two sizes, at least, for the threads beii. 
 coarse, and there being so much metal to 
 cut out, it would be almost impossible to 
 cut the thread otherwise, without tearing 
 them. For hardening and tempering taps, 
 
 6* 
 
22. 
 
 23. 
 
THE BOSTON MACHINIST. 67 
 
 see articles on "Hardening and tempering 
 tools." 
 
 72. Fluted Reamers. 
 Fluted reamers should first be turned to with- 
 in a thirty -second of an inch of the required 
 size, and then heated and allowed to cool ii 
 upright position, before finishing. This takes 
 out the strains, and the hardness • in 
 
 places by hammering out, so that they will 
 not spring when heated for hardening. In Sat- 
 ing reamers, merely fluting them with an 
 number in view of preventing tl, shat- 
 
 tering, is not sufficient For when 
 chatters, it jumps from lip to lip; hence it is 
 necessary to make the lips uneven. Flutes in 
 reamers from one-fourth to 1i itlis of an 
 
 inch in diameter, should be five. The number 
 in reamers from five-eighths to one inch, should 
 be seven. The number in r< from one 
 
 inch to one and a fourth, should be nine. The 
 number from one and a fourth to one and a 
 half inches should be eleven. 
 
 73. How to make a Fluted II 
 Have the head forged to fit a certain wrench. 
 Then make good centres in it, for these are ne- 
 

 68 THE BOSTON MACHINIST. 
 
 cessary to keep it true. Turn it to within a 
 thirty-second of the required size, then heat it 
 and let it cool in an upright position. Then, 
 turn the part designed for the lips, one-hun- 
 dredth of an inch larger than the size at which 
 you intend to finish it, then turn a place in the 
 middle of it five-eighths long, and one-twelfth 
 of the reamer's size, smaller than it is. This is 
 the place to pene it straight, after hardening. 
 After turning all but the upper part (which is to 
 be turned after it is hardened and straightened), 
 you commence fluting it, by putting it on the 
 centres, -and if you flute it on a planer, use a 
 round-end tool, one- tenth of an inch in thick- 
 ness, and plane it down to the face of every 
 lip, down to the bottom of the place made for 
 pening, and plane them so that in every other 
 two of the lips, the space between them will be 
 shorter than that of the two preceding them. 
 After doing this, use a square end tool, and 
 plane off the back side of the lips, up to within 
 a thirty-second of an inch of the face. The 
 faces of these lips should be planed straight 
 with the centre. File the lips smooth, then 
 harden it. For hardening it again, see articles 
 on " Hardening and tempering tools." Then 
 pene it straight. Then, turn the upper part to 
 
THE BOSTON MACHINIST. 
 
 69 
 
 24. 
 
 25. 
 
THE BOSTON MACHINE 71 
 
 the size required and polish it. And then 
 grind the lips down to size, and have them 
 sharp, and it is finished. 
 
 74. Half-round Reamers. 
 
 Half-round reamers should never be made, 
 in this age, but should be superseded by a sin- 
 i reamer, made in the following style, 
 a piece of steel, and have the head forged, 
 for a certain wrench, and as single-li] 
 ers usually taper, turn it t; _ r , and perfect- 
 
 ly round. Then put it on centres, and with a 
 small round point tool, plane a groove ihn 
 the whole length of it. One side of this 
 groove forms the li] on from u 
 
 plape off l irth of an inch, half \ 
 
 round. File up the lips, on a line 
 
 through the centre, on the end. Harden and 
 temper, and it is done. 
 
 75. Base Ream 
 
 These reamers are only used for boring out 
 holes that have b en cored, and cannot other- 
 wise be drilled. They sometime a hole 
 through them, and are, where large < 
 quired, generally fitted upon an iron shaft, 
 which is afterwards turned off to the same size 
 
72 THE BOSTON MACHINIST. 
 
 
 as the reamer. Their ends should be square, 
 with the corners taken off. Their lips should 
 be cut about nine to the inch, on the end, and 
 a little hooking. Harden the same as other 
 reamers. 
 
 76. Counter-boring Tools. 
 
 To make a counter-boring tool, first fit the 
 shank to a certain collet, then turn the govern- 
 or, which should not be more than a quarter of 
 an inch long, and after this, turn a place for the 
 lips, about three-eighths of an inch long, on 
 small ones, and about three-fourths on large 
 ones. Beyond this place, turn it about one- 
 third larger than the governor, and straight, up 
 to the shank, by leaving the place for the lips 
 short, and thus, it saves filing. You will then 
 file four lips in them spiralling, like a drill, then 
 file off the back side of the lips on the end, up 
 to an edge, harden, and it is done. Flat coun- 
 ter-boring tools are only made by ignoramuses, 
 who break as fast as they make them. 
 
 77. Making Dies for Screw-cutting. 
 
 In making dies for screw-cutting, they 
 should, wherever practicable, be lapped with a 
 taper tap, as they cut more easily and wear 
 
Tin: B HACHlNIf 
 
 . than those which are cut jbt, and 
 
 ed oif, to make the screw "tal. 
 Very fine tl. it well 
 
 with straight did iall dies, or d low 
 
 irth of an inch in size, should 
 three lips In them. Dies from one-fourth to 
 -half should have* four lips in them. Dies 
 ii three-fourths to one inch should h. 
 lips in them; and dies from an inch to an i 
 and a half should have - lips in them. 
 
 cuts through dies Bhou only twice the 
 
 the tl t to 
 
 make them free th m chi] 
 
 :i cut i- o deep they are liable to to 
 on the fa 11 raw 
 
 oolo 
 
 78. M 
 Thin millii Is or cutl should be 
 
 chucked to ii 'von the arbor of the ma- 
 
 chine, in order that they may not be mall 
 
 r hardening. Thev should then rned 
 
 to within a thirty-second of th 
 
 3, and then. tin heated before finishing. 
 
 The heating a second time takes out the strains 
 and hard pla< that they arc .able to 
 
 spring when heated for hardening. 
 
 7 
 
74 THE BOSTON MACHINIST. 
 
 79. Proportionate numbers of Teeth, in different 
 
 sizes. 
 
 The number of teeth to the inch in different 
 cutters, should vary in proportion to their sizes. 
 Very thin cutters of all sizes should be cut 
 very fine, as they are very easily broken when 
 the teeth are coarse. The following list will 
 probably give as good proportions as can be 
 well arrived at. At least I have spent consi- 
 derable time in " figuring them out," andean 
 find none that I think better. 
 
 Cutters one-tenth of an inch thick, should 
 have thirty teeth to the inch for large sizes, 
 and thirty-five for small sizes. 
 
 Cutters from one-eighth to three-sixteenths 
 in thickness, should have twenty-five to the 
 inch for large sizes, and thirty for small sizes. 
 
 80. Proportions of Broad Gutters. 
 
 Cutters half an inch in diameter, should be 
 cut thirty to the inch; and contain eighteen 
 teeth, of one-sixteenth of an inch deep. 
 
 Cutters three-fourths of an inch in diameter, 
 should be cut thirty- two to the inch and con- 
 tain twenty -four teeth of one-fifteenth of an 
 inch deep. 
 
THE BOSTON MACHINE 
 
 Cutters one inch in diameter, should be cut 
 tie inch, and contain twen 
 i, of one-fourteenth of an inch de< 
 Cutters one and a half inches in diameter, 
 should be cut tv. our teeth to the ii 
 
 and contain thirty side teeth, one-twelfth of an 
 inch 
 
 :wo inches in diameter, should be 
 cut tw< th to the inch, and contain forty 
 
 h, cut one-tenth of an inch de 
 Cutters three inches in diamet 
 sixteen to the inch, and contain forty-eight 
 ..th of an inch deep. 
 Cutt« r inches in dian ild be 
 
 thirteen to I contain fifty-two teeth, 
 
 cut i .th of an inch 
 
 Cutt ra five in in dian -hould be 
 
 i to the inel . contain fifl 
 
 . rut one-fifth of an inch de 
 Cuttei inches in diameter, should be cut 
 
 ten to the inch, and contain . cut 
 
 an inol th of tl 
 
 cutters should always be cut hooking, and the 
 zes should be left near nth of 
 
 an inch thick at the edge. The outer surface 
 of the cutter should be draw-filed nearly 
 square with the fac< cut more 
 
76 THE BOSTON MACHINIST. 
 
 smoothly than when filed too sharp. Harden, 
 and draw to a straw color. 
 
 81. Punches and Dies. 
 
 In making these, it is necessary to fit the 
 piece intended for the die into the slide or 
 plate of the punch, and } r ou may then put it 
 in its place, and run the slide which holds the 
 punch, down upon it. This slide is nearly 
 round, and you may, after running it down, 
 mark around it upon the piece intended for 
 the dies, and cut your die, so the centre of it 
 will come in the centre of the place marked on 
 it. The die should be cut through square with 
 its face. Such dies should be made higher 
 in the centres, or where the hole is cut 
 through, than its general surface, in order 
 that they may be ground off when dull; After 
 finishing the die, harden it, and put it into its 
 place. Then fit the shank of the piece intend- 
 ed for the punch into the slide, then put the 
 punch into the slide, and run it down upon the 
 die. Then mark through the die, on the end 
 of the punch, its desired shape. Then take 
 out the punch and cut it down very nearly 
 to the mark, and you may then put the punch 
 into the machine again, and press it into the 
 
Til MACHINIST. 77 
 
 die an i i_ r iith of an inch, and tliis will : 
 ipe perfectly. Harden, and it is finished. 
 
 82. Mai tuges. 
 
 In the making of gauges, or forms for cut- 
 or drilling machinery, it would be impos- 
 sible to give any correct details, as the styles and 
 shapes are too numerous, and I can only - 
 that it is i) ave them enough larger 
 
 before hardening, to allow for what they will 
 contract, or spring, when hardening. A 
 hardening, they should be ground, 00 DM 
 nery made for the purp 
 
 Gauges for drilling may be m * their pro- 
 
 per size b harden a they cannot be 
 
 ground after hardening. 
 
 83. M 
 Although balance-wheels have been Died for 
 3, the mode of applying them 
 seemed never to hi >wn. I there- 
 
 fore endeavored I rtain this, and ha 
 
 I that every balance-wheel should be 
 speeded up, so as to run twice or three timet 
 last as the crank-shaft it is intended to balance; 
 and that where a balance-wheel is applied in 
 this way, it makes the machine run a great 
 
THE BOSTON MACHINIST. 
 
 deal more steadily, for when the balance-wheel 
 is geered into the crank-shaft, and runs two or 
 three times faster than the crank-shaft, it forms 
 a power of itself, when going over the centre, 
 which propels the crank-shaft until it reaches 
 the quarter where it again takes its power from 
 the machine. Although it takes an additional 
 shaft and geers to apply a balance-wheel in 
 this way, the saving of metal in the balance- 
 wheel fully compensates for the extra labor, 
 for when a balance-wheel is speeded three 
 times as fast as the crank-shaft, it needs only 
 one-third of the metal in it that it would, were 
 it not speeded up at all, and if balance-wheels 
 were applied in this way generally, it would 
 make all engines run far more steadily. 
 
 84. A few words as to Master Mechanics. 
 It may safely be said that not one master me- 
 chanic in twenty knows his business thorough- 
 ly. ' Nineteen of that twenty will only buy 
 such heavy tools as he is forced to have in or- 
 der to do his business, and then, for the want 
 of a few small tools, that would cost compara- 
 tively nothing, some cotton waste with which 
 to keep them clean, and a little care to see 
 that it is done, his shop will be encumbered 
 
MACHINE 
 
 ibbish and filth, his lath mill- 
 
 machint, etc., etc., coy ith grease, so 
 
 >r use, and his men spend one- 
 third of their time, looking for a bolt, strap of 
 iron, or some other petty thing, of >>rth 
 
 than the time Spent in lookii:_ r them. 
 
 the s to ruin. 
 
 1 all this, for the want of a superintendent 
 
 on 
 duty. Th do not aj 
 
 shops v. 
 
 vn that they are The 
 
 •hanic who knows his ] loroughly, 
 
 will have every tool kept e ad in ItE 
 
 will hav dent number of t 
 
 lath ; rill and | tools, with all 
 
 other small t- i that ii<^ man i. ait a 
 
 moment for want of them: for "tine 
 money." He will keep hifl 
 and drills, as near the machines they are q 
 
 ble, and ti. e trouble, and 
 
 more likely to ensure them in their plfl 
 lie should have lor every planer, hah" a do- 
 zen straps, made of one inch by half an inch 
 iron, and bent in a D sha: ai enough 
 
 gether to hold a three-fourths inch bolt. 
 These straps need no drilling for the bolt, and 
 
THE BOSTON MACHINIST. 
 
 are far more "bandy" than straps witb boles 
 drilled through them. He should have three- 
 fourths inch bolts, of a dozen sizes, witb nuts 
 an inch thick, in order to prevent stupid work- 
 men from stripping them. He should see that 
 the centres of arbors, w T hen made, are counter- 
 sunk, perfectly three-square, and that the cen- 
 tres of the lathes likewise are kept perfectly 
 three-square. Unless he does this, the arbors 
 will spoil the centres of the lathes, and the cen- 
 tres of the arbors will soon w r ear out of true r 
 and the arbors thus be rendered worthless. He 
 should have plenty of drills, so they need not 
 be altered every time he has a new hole to drill. 
 He should have holes for drills in all small col- 
 lets, of such a size, that one drill can be used in 
 any part of the shop ; and the large ones like- 
 wise.