THRIVING after the FALL

The Index · A subject

Copper and tin

The copper pan, the kettle and the still, and the tin that keeps the copper out of the food.

9 documents · 1 chapter · 36 rows

In the chapters

Documents 9

Sources

  • Practitioner A tinner

All the sources

In the log 36

  • 19 confirmed
  • 12 amended
  • 1 partly confirmed
  • 3 unresolved
  • 1 dropped
  • 16 marked for safety
  • I47 amended Safety Pewter and old solder carry lead, up to 40 % in ley pewter; reject above 1.8 % Pb by the density test
  • W2 unresolved Safety Lead-tin solder must be hacksawed off before any heat: liquid lead penetrates hot copper (hot shortness)
  • W3 confirmed Safety Cadmium-bearing silver brazing rods give a toxic fume with no warning; use cadmium-free ISO 17672 alloys; spelter (60/40 brass) gives zinc fume
  • W4 confirmed Safety Bare copper plus acid (vinegar, wine, tomato, apple, whey) gives verdigris, an emetic; every pan that meets acid is tinned
  • W49 amended Safety Pewter: fine 95 to 99 % Sn with 1 to 4 % Cu; trifle 80 to 85 % Sn with 10 to 15 % Pb; ley 20 to 40 % Pb; reject above 1.8 % Pb; pre-1986 solders 50/50 and 60/40; …
  • W5 confirmed Safety Sal ammoniac at tinning heat gives off ammonia and hydrogen chloride: work outdoors, wind at your back
  • W50 amended Safety Lead assay: density (Sn 7.29, Pb 11.34 g/cm³, so 1.8 % Pb is about 1 % denser than tin), tin cry, streak on paper, melt (tin 232 °C, Sn-Pb eutectic 183 °C at 61.9 % Sn)
  • W52 unresolved Safety Hot-dip tinning: 15 to 20 kg tin bath, 25 mm flux blanket of tallow with sal ammoniac, dwell 60 to 90 s; the same document offers 80 % ZnCl2 / 20 % NH4Cl and bars zinc …
  • W6 amended Safety Tin must be block tin 99.9 % or better, no lead or cadmium; never solder, pewter or roofing sheet; German food law (LFGB) forbids lead and cadmium in tin linings
  • W8 amended Safety The jam pan goes unlined because sugar at that strength does not take copper
  • W9 dropped Safety Linseed rags heat themselves and ignite at about 120 to 150 °C; lay flat outdoors or in a tin of water
  • F10 amended Safety Chickpea Ascochyta at 1.1 mm rain; do not save seed from affected plants; thiram/copper dressing kills inoculant
  • B13 amended Safety Scald safety: 200 l at 62 °C from a 50 l copper lit at four; over-scald >62–63 °C cooks skin and sets bristles (only remedy skin the pig), under 58 no release, loosening …
  • B14 unresolved Safety Fat fire: tallow catches at ~200 °C and above, a wood fire under an unwatched kettle reaches it in minutes; lid or sand, never water (fireball); kettle never left, never …
  • M8 amended Safety Only tinned copper, glazed earthenware, steel or scalded wood; bare copper spoils milk within the hour
  • D5 amended Safety Copper still: plumbing grade (Cu-DHP) not wire (Cu-ETP); joints riveted or silver-soldered, never lead solder; cut off every old solder joint; scrub black film after …
  • K48 confirmed 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) …
  • W12 confirmed Ötzi's copper axe: found 1991 on the Tisenjoch, about 5,300 years old, near-pure copper, cast then cold-hammered at the edge
  • W14 amended The Kupfergraben is named for a copper works on its bank
  • W15 amended Copper conducts heat about 2× aluminium, 5× cast iron, 25× stainless
  • W16 confirmed Egg whites whisked in copper hold their foam better
  • W17 confirmed Copper slips on twelve planes; annealed yield 60 to 90 MPa, work-hardened over 250 MPa near the 350 UTS; cue: the hammer bounces and the note rises after one or two …
  • W18 confirmed Anneal at dull red about 600 °C (forge 600 to 800); water quench does not harden copper, spalls the black cupric oxide, red cuprous oxide remains; pickle in 10 % citric …
  • W21 confirmed Villedieu-les-Poêles has made copper pans since the 1200s; the firm in the window since 1830
  • W23 confirmed John Fuller, Art of Coppersmithing, 1894, the last coppersmith's manual; the cramped joint: feather to half thickness, tabs alternately up and down, hammered on a …
  • W24 confirmed Silver brazing alloy about half silver with copper, zinc and a little tin (ISO 17672 Ag 156: 56 Ag, 22 Cu, 17 Zn, 5 Sn); brazing gap 0.05 to 0.10 mm
  • W25 amended Pliny, Natural History 34, c. 77 AD: tinning of bronze invented at Alesia in Gaul, indistinguishable from silver
  • W26 partly confirmed Theophilus, De diversis artibus, c. 1120, gives a tinning method; the Kesselflicker worked Brandenburg villages until the 1950s and the trade ended in the 1960s
  • W27 confirmed Tinning window: pan a little above 232 °C, about 250 to 280; water drop skates; flux burns and tin goes yellow then purple and beads if too hot; steps if too cold; 0.45 …
  • W28 confirmed Never quench a freshly tinned pan: the tin skin cracks from the copper
  • W29 confirmed Re-tin when copper shows in a patch the size of a large coin; grey tin is harmless surface oxide
  • W30 confirmed The still is left bare because hot copper binds the wash's sulphur compounds as black copper sulphide, scrubbed off between runs; a tinned or stainless head gives a …
  • B54 confirmed Fat: cow 30–40 kg fat and 40 kg bone; pig 12 kg fat and 10 kg bone; render within 12 h or hold ≤7 °C (Reg 853/2004); suet 86–90 % lipid, trim 62–76 %; dry rendering …
  • B55 confirmed Storage: stoneware crock with lid in the cellar, tallow a year, lard 6–9 months, salt layer on top; enemies light, warmth, air, iron/copper; rancid = paint smell, not …
  • D43 confirmed Copper strips sulphur compounds as black copper sulphide; a steel still makes a spirit that smells of the ferment
  • T46 confirmed A table of twelve in forged steel and pewter costs about 520 smith-hours and 340 kg charcoal