Thimble: the Pitted Iron Thimble Gilt Inside (Rouy and Berthier, Ure 1839)

The Paris method of Rouy and Berthier: thin sheet-iron discs, red-hot, punched step by step into a cup through five ever-deeper hollows, then turned, pitted and annealed on the lathe, gilt inside with gold leaf pressed on by a steel mandril, and banded outside with a gold fillet. Variable: closed (pitted round end) or open (no end, for tailors). Source: Andrew Ure, Dictionary of Arts, Manufactures and Mines (1839), 'Thimble'. Picture: a modern pitted thimble (Commons, CC BY-SA 3.0).

متقدم

Unknown

التعليمات

Punch the blanks

Cut sheet iron 1/24 in thick into strips sized for the thimbles. Run them under a punch press to cut discs about 2 in across, left joined by a tail, a dozen to a strip.

المواد لهذه الخطوة:

صفيحة حديد (مطروقة)1 1/24 in

الأدوات المطلوبة:

مكبس تخريم

Sink the cup

Heat the blanks red-hot and lay each on a mandril fitted to its size. Strike the middle with a round-faced punch about as thick as a finger to sink it into the first hollow, then drive it through a block with five hollows of increasing depth until it has the thimble's shape.

الأدوات المطلوبة:

كور الحدادة

ملقط

معدن غير معروف

مطرقة

Turn and pit on the lathe

Chuck the rough thimble in the lathe, polish the inside, turn the outside, mark the rings for the gold band, and press in the rows of pits with a milling tool.

الأدوات المطلوبة:

مخرطة معادن

أداة التخشين

Anneal, gild and band

Anneal and brighten the thimbles. Line each inside with a thin cone of gold leaf, bonded to the iron by the hard pressure of a smooth steel mandril. Turn an annular seat outside, lay a gold fillet in it and press its edges into a fine groove cut on the lathe.

المواد لهذه الخطوة: