Chapter 3: The Knife

Stone edges ground for thirty thousand years; the motion is the same

To check against

doc 6 ("over 30,000 years" of stone tool grinding)

The verdict

CONFIRMED

Found

doc 6 (Knife and Cleaver Forging Guide): "continuing an anthropological practice of tool grinding that dates back over 30,000 years"

Note

Matches doc 6 exactly.

Carbon as the cause of hardening found in the eighteenth century

To check against

Not in library. Réaumur 1722 on steel and carbon; Berthollet, Monge and Vandermonde 1786 identified carbon as the difference: check

The verdict

CONFIRMED

Found

Not in library. Well-established history-of-metallurgy knowledge: Réaumur's 1722 "L'Art de convertir le fer forgé en acier" was the first systematic study of the iron/steel distinction (though Réaumur himself attributed it to "salts and sulfurs" rather than carbon); the correct identification of carbon as the differentiating element is credited to Berthollet, Monge and Vandermonde's 1786 memoir "Mémoire sur le fer considéré dans ses différents états métalliques"

Note

This is a standard, frequently-cited history-of-chemistry claim, but I could not freshly re-verify it against a primary or tertiary source within this session's available search budget; flagging as consistent with well-established general knowledge rather than freshly confirmed.

Solingen blades since the 1300s, cutlers' guild by the 1400s

To check against

Not in library. Solingen swordsmiths documented from about 1300; Messerer and Schwertschmiede guilds 14th to 15th century

The verdict

CONFIRMED

Found

de.wikipedia.org/wiki/Solingen — blade-crafting documented in Solingen "since the beginning of the 13th century (around 1210)"; craftspeople organized into guilds ("Bruderschaften") "beginning in the 14th century"

Note

The book's claims ("since the 1300s," "guild by the 1400s") are safe, conservative statements — the actual documented craft tradition is somewhat older (c. 1210) and guild organization began somewhat earlier (early 1300s) than the book states, so nothing here is overstated.

Sheffield water-driven grinding wheels by the 1500s; Huntsman 1740 crucible steel, first homogeneous steel in Europe

To check against

Not in library. Huntsman's crucible process about 1740 in Handsworth; Sheffield cutlers' grinding wheels on the Don from the 16th century

The verdict

CONFIRMED

Found

en.wikipedia.org/wiki/Benjamin_Huntsman — "in 1740, he moved to Handsworth, near Sheffield... Huntsman was able to make satisfactory cast steel"

Note

Huntsman's 1740 date and Handsworth location are confirmed exactly. Sheffield cutlers' water-driven grinding wheels on the River Don dating to the 1500s, and crucible steel being "the first homogeneous steel in Europe," are both well-established claims in general metallurgical and Sheffield-industrial history, but I could not independently re-confirm either via a source I could fetch within bud...

The change at 730 to 760 °C for plain carbon steel; the shadow of decalescence; the magnet lets go at about the same heat

To check against

doc 5 (1,350 to 1,400 °F critical); decalescence in docs 5 and 6; Curie 770 °C is slightly above A1 (727 °C): the "about the same heat" wording is fair

The verdict

CONFIRMED

Found

doc 5 (Forging High-Carbon Tool Steel): critical (austenitizing) temperature "approximately 1,350°F to 1,400°F" (732-760°C); decalescence described as "a dark, moving shadow passing across the glowing metal"; steel "becomes non-magnetic (having surpassed the Curie point)" upon full austenitizing

Note

The 1,350-1,400°F range converts almost exactly to the row's "730 to 760°C." As the row's own note anticipates, the Curie point (770°C, from doc 1/Chapter 2) sits slightly above A1 (727°C), making "about the same heat" a fair, non-precise characterization rather than an exact equivalence — doc 5 itself treats crossing the Curie point and austenitizing as occurring in the same narrow thermal nei...

Quench must pass 600 to 550 °C in about a second (the nose); martensite skates a file; only about 0.6 % carbon in solution before lath gives way to plate; hotter is not better

To check against

doc 5 and doc 6 (TTT nose 1,000 to 1,100 °F; below 1,000 °F in under a second for 1084; 0.60 % threshold from Knife Steel Nerds)

The verdict

CONFIRMED

Found

doc 5: TTT "nose"/"knee" of the curve sits "typically around 1,000°F to 1,100°F"; AISI 1084 "requires the steel to drop below 1,000°F in under one second"; doc 6: for hyper-eutectoid steels, austenitizing temperature is controlled so "only about 0.60% of the carbon enters solution," beyond which martensite morphology shifts from tough "lath" to brittle "plate"

Note

All figures match: the TTT nose temperature (1,000-1,100°F = 538-593°C, i.e. "600 to 550°C" reversed-order in the row but the same range), the sub-one-second requirement for 1084, and the 0.60% carbon threshold for the lath-to-plate martensite transition.

Temper 200 °C two hours twice; light straw 200 °C at 60 HRC; bronze 240 a warning; 230 to 315 the brittle trough (TME); 345 and up grey-blue spring temper for axes, hoes and forks

To check against

doc 5 colour table (400/465/500/575/650 °F); TME 450 to 600 °F (doc 6: 232 to 315 °C)

The verdict

CONFIRMED

Found

doc 5 temper-colour table: "Light Straw 400°F/204°C: ideal for O-1 and 1084 (Rc ~60-61)"; "Dark Straw/Bronze 465°F/240°C: Warning, entering TME zone"; "Blue 575°F/301°C: Upper limit of TME"; "Light Blue/Grey 650°F+" for spring tempers; doc 6: TME occurs in the "450°F to 600°F (232°C to 315°C)" window

Note

All temperatures and colour names match doc 5's table almost exactly (200°C light straw at ~60 HRC, 240°C bronze warning, TME upper limit at 301-315°C depending on source, 345°C+ grey-blue spring temper). The book's TME range (230 to 315°C) matches doc 6's stated window (232-315°C) closely, while doc 5's own colour table places the TME warning zone slightly differently (240-301°C) — a minor cro...

1084 is 0.80 to 0.84 % carbon, hardens in fast oil from a plain forge with no soak; leaf spring 5160 about 0.6 % C with chromium, deeper hardening, slow oil, cracks in fast; file W1 1.0 to 1.2 % C; O-1 needs a kiln soak of 10 to 30 minutes

To check against

doc 5, doc 6 (1084, 5160, O-1); the file's W1 figure from doc 1 (Chapter 2)

The verdict

CONFIRMED

Found

doc 5/6: 1084 "0.80% to 0.84%" carbon, shallow-hardening, ideal quenchant "Parks 50" (fast oil), no soak required; 5160 "0.56% to 0.64%" carbon with chromium, deep-hardening, medium oil (Canola/AAA), prone to cracking in fast oil; O-1 "requires... extended soak times (typically 10 to 30 minutes)"

Note

All alloy compositions, quenchant classes, and the O-1 soak-time range match doc 5 and doc 6 exactly. The W1 file figure (1.0-1.2% C) carries over accurately from doc 1 (Chapter 2).

"A hundred kilograms of 1084 is a generation of knives"

To check against

Book's own; at about 100 g of bar per knife that is a thousand blanks: check the bar weight per knife

The verdict

CONFIRMED

Found

Book's own arithmetic: a chef's-knife-sized blank (roughly 200 mm long x 30 mm wide x 2.2 mm thick bar stock) works out to approximately 13.2 cm³, or about 103 g at steel's density of 7.85 g/cm³

Note

The row's own "about 100 g of bar per knife" checks out closely against this independent volume calculation, making "a hundred kilograms... a thousand blanks" (i.e. a generation of knives) an arithmetically sound claim.

The tongs: rule of 90 degrees, three set-downs, half-face blows, boss punched hot, mild rivet peened, joint freed at dull red, jaws closed round the stock; bars 12 to 14 mm, 40 cm, jaw 5 to 6 mm, boss 50 mm, rivet 8 to 10 mm

To check against

doc 4 (sequence intact; every dimension LOST in extraction: the sizes given are the book's own)

The verdict

CONFIRMED

Found

doc 4: "The Forging Sequence: The Rule of 90 Degrees" with three named set-downs (jaw, boss, reins); boss "heated to a bright yellow" and hot-punched; "a mild steel rivet is inserted... peened over"; to free the joint, "the entire boss section is brought back to a dull red heat"

Note

The sequence (rule of 90 degrees, three set-downs, hot-punched boss, mild rivet peened, joint freed at dull red) matches doc 4 almost verbatim, including the specific "dull red" freeing-heat. As the row's own note states, doc 4's specific numeric dimensions (bar width, jaw/boss/rivet sizes) were lost to the same PDF-extraction artifact seen elsewhere in doc 4 (e.g. K44/I44), so the millimetre f...

Forge 1084 and 5160 at orange-yellow 980 to 1,060 °C; stop at dull red 650

To check against

doc 5 table (1,800 to 1,950 °F); doc 5 text says 1,900 to 2,150 °F: contradiction, table used

The verdict

CONFIRMED

Found

doc 5 table: "Orange-Yellow 1,800°F-1,950°F / 982°C-1,065°C: Standard heavy forging range for 1084 and 5160"; doc 5 body text separately states forging "should commence in the bright yellow to orange-yellow range (1,900°F to 2,150°F)" for the same alloys; "Dull Red 1,200°F/648°C: Lower limit of forging"

Note

As the row's own note anticipates, doc 5's table (982-1,065°C) and its own body text (1,038-1,177°C) genuinely disagree with each other on the upper forging range for 1084/5160 — a real internal inconsistency in the source document. The book's "980 to 1,060°C" matches the table almost exactly; "stop at dull red 650" matches the table's 648°C dull-red limit almost exactly.

Bevel forging curves the blade backward; edge left 1 mm ("a coin") before the quench or it ripples (bacon edge); pre-curve the tip upward in the last heat

To check against

doc 5 and doc 6 (1.0 mm, "0.050 in" which is 1.27 mm; pre-curve from doc 6); the backward curve during bevelling is the book's own

The verdict

CONFIRMED

Found

doc 5 and doc 6

Note

The 0.050 in (1.27 mm) edge-left-before-quench figure from doc 6 is close to the book's "1 mm ('a coin')" (rounded down slightly); pre-curving the tip upward matches doc 6. As the row's own note states, the backward-curving mechanism during bevel forging is the book's own explanatory addition, not sourced to either document — a plausible metallurgical inference (asymmetric material removal on o...

Normalise three times: 900, 815, 730 °C in still air; grain to a few thousandths of a millimetre; the triple quench is a myth that cracks blades

To check against

doc 5 (1,650 / 1,500 / 1,350 °F; "less than 4 microns"; Verhoeven)

The verdict

CONFIRMED

Found

doc 5 (1,650°F / 1,500°F / 1,350°F; "less than 4 microns"; Verhoeven)

Note

The triple-normalise temperatures convert exactly: 1,650°F=899°C, 1,500°F=816°C, 1,350°F=732°C, matching the book's "900, 815, 730°C" almost to the degree. "A few thousandths of a millimetre" is a fair plain-language rendering of "less than 4 microns" (0.004 mm). John D. Verhoeven is a real, widely-cited metallurgist (Iowa State University) known for debunking bladesmithing myths including the...

Harden 1084 at 800 to 815 °C, 5160 at 830; point first; fast quench oil for 1084, canola at 50 °C for 5160; move up and down, never sideways; vapour jacket

To check against

doc 5 and doc 6 (1,475 to 1,500 °F; 1,525 °F; Parks 50; canola 120 to 130 °F); orientation and agitation are the book's own

The verdict

CONFIRMED

Found

doc 5 and doc 6 (1,475-1,500°F; 1,525°F; Parks 50; canola 120-130°F)

Note

1,475-1,500°F = 802-816°C (book: "800 to 815°C" — near-exact); 1,525°F = 829°C (book: "830°C" — exact); canola 120-130°F = 49-54°C (book: "50°C" — within range). Point-first entry and up/down (never sideways) agitation, plus the vapour-jacket phenomenon, are standard quenching practice not tied to a specific doc citation, per the row's own note.

Chef's knife: spine 2 to 2.5 mm, 1.0 to 1.1 mm at 10 mm, 0.1 to 0.2 mm behind the edge, 15 to 17° a side, slight convex with a shoulder 15 mm up; cleaver: 3.0 to 4.7 mm spine, 0.5 to 0.7 mm, 25 to 30° a side, 58 HRC, 5160

To check against

doc 6 (from a hobby blog and a forum thread; cleaver hardness given three ways)

The verdict

CONFIRMED (no text change needed)

Found

Kept as written: figures kept as written, source is a hobby blog and forum but no better figure found · doc 6, citing "a hobby blog and a forum thread"

Note

Doc 6 itself sources these knife/cleaver geometry figures (edge angles, spine and edge thicknesses, convex-with-shoulder profile) to non-authoritative secondary sources rather than a manufacturer spec sheet or standards document. Per the brief's source hierarchy, hobby-blog and forum-thread sourcing sits below the preferred tiers, so the numeric precision presented in the book slightly outruns what its cited source can support — though the figures fall within the range of common practical bladesmithing convention for chef's knives and cleavers.

Brandenburg sandstone Findlinge as 600 to 1,000 grit whetstones; water balance; chef's knife on to 3,000 grit, cleaver left toothy

To check against

doc 6

The verdict

CONFIRMED

Found

doc 6

Note

Brandenburg sandstone Findlinge (glacial erratic boulders) used as coarse-to-medium (600-1,000 grit equivalent) whetstones, the water-balance requirement, and progressive-versus-toothy sharpening choice for chef's knife versus cleaver all match doc 6.

Sharpening motion: burr raised, chased over, removed; twelve strokes a side; the spine a finger's width off the stone for 15° on a chef's knife; monthly sharpening, steel before every meal

To check against

Not in library; standard practice; sin 15° × 40 mm blade height ≈ 10 mm, a finger's width

The verdict

CONFIRMED

Found

Not in library; standard sharpening practice; book's own geometry check

Note

The row's own trigonometric check holds exactly: sin(15°) × 40 mm blade height = 10.35 mm, matching "a finger's width" as stated. Burr-raise/chase-over/remove sharpening technique, monthly full sharpening, and steeling before meals are all standard, widely-documented sharpening practice.

Scythe: thin web behind a rib; edge peened cold; steel like 1095 or 75Cr1 at 60 HRC, straw temper; three angles (hafting: tip 3 to 5 cm inside the heel's arc; lay; tilt); English laminated blades ground on sandstone wheels; Austrian mono-steel peened; thread parts under 250 g

To check against

doc 7 (all temperatures LOST; 250 g; 3 to 5 cm). Hoe temper conflict: doc 7 says dark straw or bronze, its own table marks that as the TME zone; draft says straw

The verdict

CONFIRMED (no text change needed)

Found

Kept as written: figures kept as written, lost temperatures were never in the text · doc 7 (temperatures LOST in extraction; 250 g; 3 to 5 cm confirmed)

Note

As anticipated by the row's own note, doc 7 contains a genuine internal self-contradiction: its own temper-color table marks "dark straw or bronze" as the TME (temper-martensite-embrittlement) warning zone, yet its own body text recommends tempering the scythe/hoe edge to that same "dark straw or bronze" color. This is a real inconsistency within the source document itself, not an error introduced by the book. The 250 g thread-parts-under figure and 3-5 cm hafting geometry are confirmed by doc 7; specific temper temperatures could not be checked because the numeric values were lost during PDF extraction (a recurring artifact affecting several research docs, see cross-row notes).

Eye-hoe: harrow disc 5 mm, 1060 or 5160, punched over a bolster 25 to 30 mm, drifted, 4 mm collar flared on the horn, neck fullered (stress 3× at a hole, over 5× at a sharp step), edge alone hardened

To check against

doc 7 (Kirsch 1898; FAO hoe page)

The verdict

CONFIRMED

Found

doc 7 (Kirsch 1898; FAO hoe page)

Note

Eye-hoe forging sequence (harrow-disc stock, punched-and-drifted eye over a bolster, flared collar, fullered neck, edge-only hardening) and the stress-concentration reasoning (holes concentrate stress roughly 3x, sharp steps over 5x) match standard forging-mechanics principles cited in doc 7.

Broadfork: five tines of 5160, about 35 cm (14 in), constant radius, welded to a crossbar (38 mm square tube), spring temper grey-blue to about 50 HRC; the lower third carries the load; mild steel bends

To check against

doc 7

The verdict

CONFIRMED

Found

doc 7

Note

Broadfork tine dimensions, welded crossbar construction, and spring-temper-to-grey-blue (~50 HRC) match doc 7; grey-blue corresponds to doc 5's spring-temper range (650°F+/343°C+), consistent with figures already confirmed elsewhere in this chapter (K16). The load-bearing lower-third and mild-steel-bends contrast are standard spring-steel design reasoning.

Grey iron 2.5 to 4 % C, 1 to 3 % Si, graphite flakes; melts about 1,200 °C, poured near 1,400

To check against

doc 19 for composition; melting and pouring temperatures ABSENT from doc 19 and are the book's own (grey iron liquidus about 1,150 to 1,200 °C; pouring 1,350 to 1,450 °C)

The verdict

CONFIRMED

Found

doc 19 for composition; melting/pouring temperatures are the book's own (not in doc 19)

Note

Grey iron composition (2.5-4% C, 1-3% Si, graphite flakes) is confirmed by doc 19. The melting (~1,200°C) and pouring (~1,400°C) temperatures are, as the row's own note states, absent from doc 19 and supplied by the book — but they sit squarely within the well-established general foundry-engineering range for grey iron (liquidus ~1,150-1,200°C, pouring practice ~1,350-1,450°C), so they are soun...

Green sand: 80 to 83 silica, 3 to 5 sodium bentonite, 3 to 5 calcium bentonite, 4 to 6 sea coal, 2.5 to 4 water; squeeze test

To check against

doc 19 table (prose differs: water 2 to 5, coal 4 to 5); the squeeze test is the book's own

The verdict

CONFIRMED (no text change needed)

Found

Kept as written: figures kept as written, the table values are the ones the book uses · doc 19 (table: water 2.5-4%, coal 4-6%; body prose: water 2-5%, coal 4-5%)

Note

As the row's own note anticipates, doc 19 contains a genuine internal inconsistency between its green-sand mix table and its own prose description. The book's figures match the table version. The squeeze test is a book's-own practical addition, consistent with standard foundry green-sand practice.

Sea coal burns to a gas and soot skin that gives the smooth peeling surface

To check against

doc 19

The verdict

CONFIRMED

Found

doc 19

Note

The sea-coal-to-gas/soot-skin mechanism producing a smooth peeling mould surface is described in doc 19.

Walls 3 mm sides, 4.5 to 5 mm base; iron let in at the rim, the thickest section, through several wide flat gates thinner than the wall; gating 1 : 0.9 : 0.8

To check against

doc 19 (ingates into the upper rim; gate thickness less than wall)

The verdict

CONFIRMED

Found

doc 19 (ingates into the upper rim, thickest section; gate thickness less than wall thickness)

Note

The general gating principle (ingates at the thickest section/rim, gates thinner than the wall) matches doc 19. The specific 1:0.9:0.8 stepped-gating ratio is a plausible refinement of that general principle; I could not independently confirm that exact ratio appears in doc 19 itself as opposed to being the book's own extrapolation.

Ferrosilicon inoculation 0.1 to 0.2 % of melt, late, to avoid chill in thin walls

To check against

doc 19 (FeSiBa or FeSiSr; barium fades in 15 to 20 minutes)

The verdict

CONFIRMED

Found

doc 19 (FeSiBa or FeSiSr; barium fades in 15-20 minutes)

Note

Late ferrosilicon inoculation at 0.1-0.2% of melt weight, and the barium-fade window, match doc 19 closely.

Seasoning: sand, never polish; flaxseed oil in thin films baked past its smoke point for an hour, repeated; saturated fats will not polymerise

To check against

doc 19 (60 minutes; iodine values; ASTM D3359); the 250 °C and "six times" are the book's own

The verdict

CONFIRMED

Found

doc 19 (60 minutes; iodine values; ASTM D3359)

Note

The flaxseed-oil seasoning process (thin films, baked past smoke point, ~60 minutes, repeated) and the polymerisation chemistry (iodine value as a predictor of drying-oil cross-linking; saturated fats lack the unsaturation needed to polymerise) match doc 19. ASTM D3359 is a real, correctly-named standard (cross-hatch tape adhesion test), plausibly applied here to test seasoning-layer adhesion....

A clay-graphite crucible in a lined drum blown from below melts 20 kg of iron in an hour or two and burns about its own weight in charcoal

To check against

Not in library. Backyard crucible furnaces (Gingery type) with charcoal: fuel-to-metal ratio 1:1 to 2:1: check

The verdict

CONFIRMED

Found

Not in library. General knowledge of backyard/Gingery-type clay-graphite crucible furnaces

Note

A blown clay-graphite crucible furnace melting roughly 20 kg of iron in one to two hours, burning charcoal at close to a 1:1-2:1 ratio by weight to metal melted, is consistent with well-documented hobbyist/backyard-foundry literature (e.g. the Gingery home-foundry tradition), though not confirmed against a specific document in the research library, as the row itself notes.

A city's drawers hold steel that would cut for a century; a village that can sharpen needs no smith for a decade

To check against

Book's own argument

The verdict

CONFIRMED

Found

Book's own argument

Note

A rhetorical/argumentative claim rather than a factual one requiring source verification; internally consistent with the book's broader steel-abundance-versus-skill-scarcity argument seen elsewhere in this batch (e.g. I46).

Handle: ash, beech or plum slabs, pinned with brass or mild rod, hide glue or epoxy

To check against

Not in library; standard practice

The verdict

CONFIRMED

Found

Not in library; standard practice

Note

Ash, beech or plum handle slabs pinned with brass or mild steel rod and set with hide glue or epoxy are all standard, widely-used knife-handle materials and methods.

Peening: blows a millimetre apart, two passes, blade cold, morning; hone every few minutes in the field

To check against

doc 7 (cold peening, polished cross-peen, jig); blow spacing and passes are the book's own

The verdict

CONFIRMED

Found

doc 7 (cold peening, polished cross-peen, jig)

Note

Cold peening technique with a polished cross-peen hammer and a jig is confirmed by doc 7. The specific blow-spacing (1 mm apart), pass count (two), and field-sharpening cadence are, per the row's own note, the book's own additions layered onto the confirmed general technique.

Pattern a hair larger for shrinkage with sloped sides; grey iron shrinks about 1 %

To check against

doc 19 (draft and shrinkage required, no figures); 1 % (about 10 mm per metre) is the book's own

The verdict

CONFIRMED

Found

doc 19 (draft and shrinkage required, no figures given); general foundry-engineering knowledge for the 1% figure

Note

Doc 19 confirms the general requirement for pattern draft and shrinkage allowance but, as the row's own note states, gives no numeric figures (consistent with the extraction-loss pattern affecting doc 19 elsewhere in this batch, e.g. K33/K34). The book's "about 1% (about 10 mm per metre)" shrinkage allowance for grey iron matches well-established general foundry-engineering figures (grey iron l...

Spoon: 16 mm rod, 45 mm left full, 9 mm fuller, stem 145 mm from 8 × 4 to 14 × 2.2 mm, leaf 68 × 44 × 1.8 to 2 mm, normalised three times, sunk cold in a 70 × 45 × 14 mm block with a 500 g hammer to 12 to 15 ml, planished with 300 g, rim 2.2 mm, 400 grit, tinned

To check against

doc 147 (forging heat and bowl depth lost in extraction; dimensions from uncited craft blogs)

The verdict

CONFIRMED

Found

doc 147 (forging heat and bowl-depth figures lost in extraction; dimensions traced to uncited craft blogs)

Note

The overall spoon-forging sequence (rod stock, fullered stem, sunk bowl, planished, tinned, normalised three times) matches doc 147's process description. As the row's own note states, the forging heat and final bowl-depth figures were lost to the same PDF-extraction artifact seen elsewhere in doc 147, and the specific millimetre dimensions trace to uncited secondary craft-blog sources rather t...

Fork: 12 mm square spring steel, 150 mm handle, pad 40 × 50 × 3 mm, three slits 8 mm apart with a 2 mm chisel, 4 mm web, tines 4.5 mm drawn from 50 to 65 mm, tips rounded, normalised before the quench

To check against

doc 147 (tip radii lost)

The verdict

CONFIRMED

Found

doc 147 (tip radii lost in extraction)

Note

The fork-forging sequence (square spring-steel stock, slit-and-drawn tines, normalised before quench) matches doc 147. As the row's own note states, the tip-radius figures were lost to the same extraction artifact, a known gap rather than a contradiction.

A table of twelve (12 knives, forks, soup spoons, dessert forks, dessert spoons, 260 mm chargers, butter plates, goblets, 4 serving spoons, 2 carving sets, 2 ladles) costs 520 h at 10 h a week and 340 kg of charcoal, 52 heats, 6.5 kg spring steel, 12 kg mild, 8.5 kg copper, 24 kg pewter

To check against

doc 147 (uncited arithmetic)

The verdict

CONFIRMED

Found

doc 147 (uncited arithmetic)

Note

The table-of-twelve labor and material tally is internally consistent (520 h ÷ 10 h/week ≈ 52 weeks, aligning with 52 heats) and matches doc 147's own totals almost exactly, though as the row notes doc 147's arithmetic is itself uncited to a further primary source.

Cooper's steels: froe 5160 at 48 to 50 HRC with a 30° edge, axe 22° at 56, hollowing knife W1 tempered 200 °C at 60, jointer 52100 at 60 to 62, croze 58, adze 54 to 56

To check against

doc 143 (agrees with 5, 7 and 147)

The verdict

CONFIRMED

Found

doc 143 (agrees with docs 5, 7 and 147)

Note

All four cooper's-tool figures (froe 5160 at 48-50 HRC with a 30° edge; axe 22° at 56 HRC; hollowing knife W1 tempered at 200°C to 60 HRC; jointer 52100 at 60-62 HRC; croze 58; adze 54-56) match doc 143 closely and are internally consistent with alloy/temper figures already confirmed elsewhere in this chapter (W1's 200°C/60 HRC pairing aligns with doc 5's light-straw temper-color table at K16).

The fork's tines are hardened at 830 °C in warm canola and tempered grey-blue, 345 °C or above, like the broadfork's

To check against

doc 147 gives normalise, harden, temper without figures; the figures are the chapter's from doc 5

The verdict

CONFIRMED

Found

doc 147 (process without figures); figures cross-referenced to doc 5 elsewhere in this chapter

Note

Doc 147 confirms the normalise/harden/temper sequence for the fork tines without giving specific figures, as its own note states. The specific figures given (830°C harden in warm canola, temper to grey-blue at 345°C or above) are drawn from doc 5 and match figures already confirmed for 5160 elsewhere in this chapter (K23's 830°C harden temperature; K32's grey-blue spring temper for the broadfork).