Making and Knowing
A minimal edition of BnF Ms Fr 640 in English Translation

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How to anneal the molds

Light your charcoals from the forge, then place them in a line in a corner of the forge according to the size of your mold, in order that it be surrounded with 3 or 4 fingers of charcoals, particularly at the bottom of the mole, where it is thicker. Then put your molds on these charcoals —— and not on a grate as some people do —— because they would get too strong a heat. Let your furnace heat up gradually for a while, always adding burning charcoal. As long as the mold is humid, your charcoal will be dampened at the bottom, but when it is dry, the charcoals start to blaze. When one side of the mold is dry, turn over; when both sides are dry and don’t smoke anymore, increase the heat and cover your mold with burning coals. When the mold starts being red, do not blow on it with small bellows, because the mold would burst. Similarly, when your mold becomes red—hot, keep it well covered with burning charcoals and do not uncover it because it would crack. Prevent the draft from a window from reaching it. Then let it cool down.

at left middle margin of folio 132r

When you want to anneal your molds, luted or not, do mark the belly of your mold, in order to place that side at the bottom, against the burning charcoals, because if the intensity of the heat made the mold crack, it would be better that it do so on the bottom part instead of the top part.

at left bottom margin of folio 132r

If your mold is small, do not heat it as long, otherwise it would crack and be damaged.

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dry by itself. When your mold starts to redden, it will soon be become completely red—hot. But make sure that its bottom is red—hot too, without any black spot.