One last note, I wanted to see what people think of stamping sheet metal gears. Is this just a novelty thing someone does for their CAD portfolio or something actually viable?
Chauncey Jerome invented a method of making clock gears in 1837 by stamping them out of sheets of brass, so it was done in the past. But today, most gears seem to be made from stronger methods like extrusion or forging. Those methods also don't produce as much scrap metal as stamping (though stamping still wastes less material than milling most of the time). There are in particular a lot of documents about this related to the US Army in the 1970's, '80s, and '90s. They mainly wanted to mass-produce cheaper and stronger gears for tanks and helicopters. The documents are about the die design and computer programs to calculate its dimensions:
I also read about thread rolling machines like this planetary thread roller (the fastest kind there is), or the other three kinds: 2-die, 3-die, and flat. They are covered here, or Wikipedia has a diagram of each type of rolling. In theory, gears could be made the same way (now that I think about it, threaded bolts are technically a very heavily angled helical gear), with a gear-shaped die rolling the blank into a gearwheel.
On 3/24/2020 at 2:35 AM, Sturgeon said:
Ever wonder how they milled intricate guns like the Browning BAR, Hi-Power, or Roth-Krnka-Steyr 1908?
For the Lewis Gun and some other WWI weapons, I don't have to wonder:
United States Common Shrapnel and Common Steel Shells, 3.8, 4.7, and 6 In. manufacturing specifications, p. 1113-1118
United States Munitions 3-In. Common Shrapnel Shell manufacturing specifications, p. 353-377
United States Munitions 3-In. Common Steel Shell manufacturing specifications, p. 486-507
United States Munitions 3 to 6 In. Cartridge Cases manufacturing specifications, p. 881-903
Three-Inch United States Navy Projectiles by Lieut. A. G. Dibrell, p. 969-976
Handling 8-In. Shell Forgings by M. E. Hoag, p. 1101-1105
And one article so large it gets its own list:
United States Munitions The Springfield Model 1913 Service Rifle manufacturing specifications:
Sleeve Operations, Part II, p. 19-27
Cocking Piece, p. 69-76
Striker, Mainspring, Extractor, Extractor Collar, Ejector, Ejector Pin, Part I p. 111-119, Part II p. 153-161
Safety-Lock Spindle, Plunger, p. 245-250
Guard, Sear, Trigger, Floor Plate, Floor-Plate Catch, Magazine Spring, Cutoff, Follower, Part I p. 287-294, Part II p. 333-338, Part III p. 551-558, Part IV p. 415-426
Movable Stud, Front Sight, Movable Base, Leaf, Slide, Cap, Part I p. 463-469, Part II p. 595-602, Part III p. 641-647
Drift Slides, Windage Screw, Butt Plate, Butt-Plate Cap, Upper Band, Lower Band, Spring and Swivel, Butt Plate Swivel, Part I p. 685-690, Part II p. 729-735, Part III p. 771-779
Stacking Swivel, Hand-Guard Clip, Front-Sight Cover, Cleaning Rods, p. 817-823
Oiler and Thong Case, Spare Parts Kit,Screwdriver, p. 947-953
Making the Stock, Part I p. 1031-1041, Part II p. 1079-1085, Part III p. 1123-1129
The Manufacture of the Lewis Machine Gun by Frank A. Stanley (at Savage Arms Corporation, continues in Volume 48), Part I p. 969-971
Building Carriages, Caissons and Limbers for 75-mm. Guns by M. E. Hoag (continues in Volume 48), Part I p. 793-796, Part II p. 861-865, Part III p. 901-904
Manufacture of the 4.7-Inch Gun Model 1906 by E. A. Suverkrop, Part I p. 519-524, Part II p. 649-658
The Manufacture of the Lewis Machine Gun by Frank A. Stanley (at Savage Arms Corporation, continued from Volume 47, continues in Volume 49), Part II p. 265-273 (February 14), Part III p. 397-403, Part IV p. 579-584, Part V p. 663-667, Part VI p. 747-752, Part VII p. 825-828, Part VIII p. 873-878, Part IX p. 949-952
Manufacture of the 75-mm. High-Explosive Shell by S. A. Hand, Part I p. 435-439, Part II p. 535-539, Part III p. 705-712
Building Carriages, Caissons and Limbers for 75-mm Guns by W. J. Larson (continued from Volume 47), Part IV p. 229-231, Part V p. 277-279
Hydraulically Operated Shell Production Machinery by I. William Chubb, p. 939-943
Making 50,000 French 75-mm. Shrapnel per Day by Robert K. Tomlin Jr (specifically about Citroën), p. 987-990
Manufacturing Base Plugs for the 80 Mark VIII Time Fuse by John Campbell, p. 414-417
The Relining of Guns at Watervliet Arsenal by E. A. Suverkrop, Part I p. 687-691, Part II p. 783-785, Part III p. 859-862
Boring and Reaming Tools for 220- and 270-mm. French Shells by James Forrest, p. 70-72
Self-Centering Driver for Rough-Turning Shells by H. A. Wilson, p. 427
Making Concrete Metal-Planing Machines by Ethan Viall (for planing beds for further gun-boring lathes), p. 603-608
Manufacture of the Lewis Machine Gun by Frank A. Stanley (at Savage Arms Corporation, continued from Volume 48, continues in Volume 50), Part X p. 25-29, Part XI p. 203-207, Part XII p. 481-484, Part XIII p. 529-531
The British 6-In. Howitzer by I. William Chubb, Part I p. 231-242, Part II p. 411-423, Part III p. 605-612, Part IV p. 697-704
How the 155-Mm. Howitzer is Made by J. V. Hunter (specifically about the 155 M1918 made at American Brake Shoe and Foundry, continues in Volume 50), Part I p. 941-945, Part II p. 983-986, Part III p. 1123-1129
The Development of the French 75-mm. Field Gun by J. A. Lucas, p. 149-152
Lathes for the Present Gun Program by A. L. de Leeuw, p. 491-493
The 75-mm Field Gun Model 1916, M.III Special Correspondence, p. 323-328
The Three-Inch Anti-Aircraft Gun, Model 1918 Special Correspondence, p. 185-190
The Engineering Division of the Ordnance Department by John H. Wan Deventer (about design and transport of weapons in general in the WWI US Army), p. 921-931
What Ordnance Is and Does by John H. Van Deventer (mainly useful as the only photo I have of an 8-inch US pre-WWI howitzer on p. 876), p. 875-881
Chilled Cast-Iron Dies for Forging and Nosing Shells by A. F. White, p. 747-748
Slotting Breech Bushings by H. W. Merrill, p. 1186
Making Boring Bars for Big Guns by M. E. Hoag, p. 987-988
Tool for Burring Inside of Dummy Cartridge Shells, p. 1048-1049
Making a Spiral Rack for the Sights on the Six-Pound Gun Mounts by Severin Seaberg, p. 470
Polishing Inside Profile of Nose on High-Explosive Shells by H. A. Wilson, p. 168
Some Types of Modern Grenades by Rudolph C. Lang, p. 139-143
Grinding 6-In. Shell-Boring Cutters by George M. Dick, p. 207-208
Manufacture of the Lewis Machine Gun by Frank A. Stanley (at Savage Arms Corporation, continued from Volume 49), Part XIV p. 55-60
How the 155-Mm. Howitzer is Made by J. V. Hunter (specifically about the 155 M1918 made at American Brake Shoe and Foundry, continued from Volume 49), Part IV p. 199-204, Part V p. 249-252, Part VI p. 303-306, Part VII p. 587-593, later acknowledgement that Schneider actually designed it and the 240-mm howitzer (apparently no one mentioned this in the main article) p. 908
The British 8-In. Howitzer by I. William Chubb (continues in Volume 51), Part I p. 1189-1194
Manufacturing the 9.2-In. Howitzer Shell by S. A. Hand, Part I p. 799-801 and 839-842, Part II p. 895-897 and 947-950, Part III p. 1089-1093
Cam Rails Used in Planing Howitzer Jackets by E. A. Thanton, p. 230
Unique Shell-Profile Turning Attachment by Donald A. Baker, p. 161-162
155 mm Howitzer Production (about American Brake Shoe and Foundry production of 155 mm M1918 howitzers), p. 162
How Ordnance is Inspected by Fred H. Colvin, Part I p. 263-267, Part II p. 311-316, Part III p. 557-563
Modern Artillery Ammunition by H. M. Brayton (continues in Volume 52), Part I p. 707-710
Finding the Cost of Ordnance by Lieut. L. S. Gatter (mainly including a 6-inch shell inspection as an example), p. 657-660
Railway Gun Mounts by Lieut. Col. G. M. Barnes (mainly about US ones), p. 329-335
The 14-In. Naval Railway Batteries by C. L. McCrea, p. 141-149
History of the Aberdeen Ordnance Proving Ground by Major F. P. Lindh (mainly only photos of artillery pieces that are useful), Part I p. 459-461,Part II p. 509-513, Part III p. 607-611
Gun-Boring Tools and Data by Fred H. Colvin (about the US 4-inch naval gun specifically), p. 997-999
Hardness Tests of Gun-Barrel Steel by William Kent Shepard, p. 739-742
How Army Ordnance Met Its Responsibilities by Brig-Gen. W. S. Peirce, p. 408-409
Making Gun-Sights for Anti-Aircraft Guns by Fred H. Colvin (most likely about the 3-In. AA gun), p. 681-684
High Production Tooling Methods as applied to the Machine-Gun Tripod, Model 1918 by Albert A. Dowd and Donald A. Baker (continues in Volume 51), Part I p. 1029-1036
Radius Link Designing by Arthur R. Melloy (about turning the points of shells), p. 993
Instruments for Hardness Tests by C. E. Clewell (about testing shells and armor), p. 93-96
The Field Mount for the 7-In. Navy Gun by C. L. McCrea, p. 523-527
The British 18-Pounder Quick-Firing Gun by I. William Chubb, Part I p. 617-621, Part II p. 733-735
The Manufacture of Artillery Range Finders by Geo H. Thomas (continues in Volume 52), Part I p. 1045-1047
Operations on the British 9.2-In. Gun by I. William Chubb, Part I p. 275-280, Part II p. 373-377, Part III p. 423-427
The Ordnance Repair Shops at Mehun-Sur-Yevre by Maj. George S. Brady, p. 575-578
Machining Problems Solved in Gun-Making, Editorial Correspondence (about the 4.7-inch gun, continues in Volume 52), Part I p. 949-952
Mounts for Naval Anti-Aircraft Guns by Fred H. Colvin (about the 3-inch AA gun in US service), Part I p. 79-83, Part II p. 457-461
The Stamets Gun-Boring Lathe by E. L. Dunn (for large-caliber guns), p. 1071-1073
The British 8-In. Howitzer by I. William Chubb (continued from Volume 50), Part II p. 13-17, Part III p. 171-176 and p. 227-230
High Production Tooling Methods as applied to the Machine-Gun Tripod, Model 1918 by Albert A. Dowd and Donald A. Baker (continued from Volume 50), Part II p. 401-407
Cutting the Rotating Rack For a Breech Block by L. E. Olson (about the breech block for the 12-inch M1895 coastal artillery gun), p. 1063-1064
Machining Problems Solved in Gun-Making by J. V. Hunter (about the 4.7-inch gun, continued from Volume 51), Part II p. 39-43, Part III p. 133-136, Part IV p. 613-616, Part V p. 733-735
Broaching the Recoil Cylinder of the 4.7-In. Gun by M. E. Infiorati, p. 977-978
The Manufacture of Artillery Range Finders by George H. Thomas (continued from Volume 51), Part II p. 249-254, Part III p. 301-304, Part IV p. 403-404
Unusual Methods of Securing Extreme Accuracy by A. L. De Leeuw (about the Canon de 75’s recoil cylinder), Part I p. 595-599, Part II p. 937-941, Part III p. 1049-1053, Part IV p. 1094-1097
Graduating Range Finder Sights by L. B. Rich, p. 1097-1098
Modern Artillery Ammunition by Capt. H. M. Brayton (continued from Volume 50), Part II p. 95-101
Manufacturing with Special Machines vs. Standard Equipment by Col. G. F. Jenks and M. H. Christopherson (about the 240 mm US siege howitzer recuperator), Part I p. 37-39, Part II p. 97-101, Part III p. 228-233, Part IV p. 349-353, Part V p. 475-479
The rest of the Lewis Gun series is like this, and most of the other articles linked in the original post are like this too. In addition Volume 52's article about the Canon de 75's recoil cylinder has been copied and reposted on that forum, with a bunch of typos corrected, images shifted around, metric values added, and links and sources about the operation and background of that recoil system:
I'm sure that today a 0.0008" tolerance on a 63" long lapped hole is nothing special, but in 1918 it was the biggest mass production achievement of WWI, believed impossible by the French and anyone else.
Production Discussion
in Open Discussion
Posted
Chauncey Jerome invented a method of making clock gears in 1837 by stamping them out of sheets of brass, so it was done in the past. But today, most gears seem to be made from stronger methods like extrusion or forging. Those methods also don't produce as much scrap metal as stamping (though stamping still wastes less material than milling most of the time). There are in particular a lot of documents about this related to the US Army in the 1970's, '80s, and '90s. They mainly wanted to mass-produce cheaper and stronger gears for tanks and helicopters. The documents are about the die design and computer programs to calculate its dimensions:
SPIRAL BEVEL GEAR AND PINION FORGING DEVELOPMENT PROGRAM- February 29, 1972
Precision Forged Spiral Bevel Gears- CAD/CAM Technique Makes It Practical- August/September 1984
Manufacturing of Forged and Extruded Gears- July/August 1990
I also read about thread rolling machines like this planetary thread roller (the fastest kind there is), or the other three kinds: 2-die, 3-die, and flat. They are covered here, or Wikipedia has a diagram of each type of rolling. In theory, gears could be made the same way (now that I think about it, threaded bolts are technically a very heavily angled helical gear), with a gear-shaped die rolling the blank into a gearwheel.
For the Lewis Gun and some other WWI weapons, I don't have to wonder:
Compilation of sources from WWI-era American Machinist volumes (includes Welin breech manufacturing)
First, a general link to the Hathitrust page with links to their American Machinist volumes during this era (Volumes 19, 20, 24, and 29-58):
https://catalog.hathitrust.org/Record/008896977
And then going in chronological order, the specific volumes where my sources are:
American Machinist Volume 45 (late 1916):
Articles in this volume:
American Machinist Volume 46 (early 1917):
Articles in this volume:
And one article so large it gets its own list:
United States Munitions The Springfield Model 1913 Service Rifle manufacturing specifications:
American Machinist Volume 47 (late 1917):
Articles in this volume:
American Machinist Volume 48 (early 1918):
Articles in this volume:
American Machinist Volume 49 (late 1918):
Articles in this volume:
American Machinist Volume 50 (early 1919):
Articles in this volume:
American Machinist Volume 51 (late 1919):
Articles in this volume:
American Machinist Volume 52 (early 1920):
Articles in this volume:
American Machinist Volume 55 (Late 1921):
Articles in this volume:
From that source, I can go to Volume 48, to Part IV of the Lewis Gun article on pages 581-583 (using the Internet Archive link), for example:
Gauges and jigs.
Gauges and jigs everywhere.
For reference on what the finished receiver of the Lewis Gun looked like, C&Rsenal's teardown has good views of most of its parts.
The rest of the Lewis Gun series is like this, and most of the other articles linked in the original post are like this too. In addition Volume 52's article about the Canon de 75's recoil cylinder has been copied and reposted on that forum, with a bunch of typos corrected, images shifted around, metric values added, and links and sources about the operation and background of that recoil system:
Canon de 75 mle 1897/ US Model 1897 recoil system function and manufacturing.
I'm sure that today a 0.0008" tolerance on a 63" long lapped hole is nothing special, but in 1918 it was the biggest mass production achievement of WWI, believed impossible by the French and anyone else.