30.8.17

Dictionarium polygraphicum. To make the common lacker varnish.


Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
Take rectified spirits of wine 2 pound, shell-lac in powder half a pound, put them into a two-quart bottle, and let them stand till the lac is quite dissolved; then strain it, and add a little common sanguis draconis in fine powder, and a litde turmerick in fine powder, both tied up in a rag; digest them for a day or two, shaking it often, and it is done.
Where take notice, That you may heighten or diminifh the colour by increasing or diminishing the quantity of the colouring ingredients.

Another LACKER.
Take rectified spirits of wine 2 pound, shell-lac half a pound: let it be dissolved, and then strain it; then, instead of common sanguis draconis, take a very little drop of fine sanguis draconis in fine powder, and English saffron dried, which tie up in a fine linnen rag, and put into the varnish, as before.
If you would have the colour deeper, or more like copper, add more sanguis draconis; but if lighter, the more saffron.

A LACKER varnish to be used without fire.
Take of the following varnish (in the next section) 2 pounds, Venice turpentine an ounce or 2 ounces; mix and dissolve it well with the varnish.
With this you may lacker or varnish any thing in the open air, which, altho' it may look dull and cloudy just after varnishing, yet will that quickly vanish, and it will obtain in a short time a pleasing and goodly lustre.


To make the best sort of LACKER varnish now used by gilders.
Take fine seed-lac varnish (which see under the article VARNISH] 6 ounces, with which mix arnotto in fine powder a sufficient quantity; set it over the fire in a gally-pot, and let it dissolve, and keep it in a bottle close stopped.

2. Take fine seed-lac varnish 6 ounces, as much gamboge in powder as it will dissolve in a gentle sand-heat; keep this also in a glass close stopped for use.

3. Take seed-lac varnish one pound, and add to it 2 spoon fuls and a half, or 2 spoonfuls of the first reserved tincture, and 5 or 6 spoonfuls of the second reserved varnish tincture; and add to this 15 grains of saffron tied up in a rag: digest them for 24 hours, having first shaken them well.

4. Then make a trial of this varnish upon a bit of silver; if you find it too yellow, put in more of the arnotto, or first reserved varnish tincture: thus increasing or diminishing the preparation, till you have brought it to the exact golden colour, which is the ultimate or only thing aimed at.


To LACKER oil-painting, sized works, or burnished silver.
Warm your picture-frame or piece of work before the fire; then having put out some lacker into a large gallipot, with a fine large and fast btush of hog's-hair, or camel s-hair, nimbly pass your work over, and be lure that you do not miss any part of it, nor yet wash the same part twice; but take special care to lay it thin, and even, and presently warm it by the fire while it looks bright; for by so doing you may lacker it again in a quarter of an hour, warming it before ana after the operation. Repeat this twice or thrice, and if you find the colour not deep enough, do it again the fourth time; but take care of ma king it too deep; for that is a fault cannot be mended.

To make LACKERING look like burnished gold
If you have before-hand burnished your silver very well, and your lacker is tinged of a true gold-colour, and you lay it on carefully with an even hand, not thicker in one place than another, matting it as you do burnished gold, it will be so exactly like gold-foil, or gilding, that it will be able to deceive the most curious eye, that shall not be before-band acquainted with the fallacy.

Here you are to observe, That in lackering carved works, you must be quick, or strike and job your brush against the hollow parts ofit, to cover them also, matting and varnishing them deeper, and more dull than other parts of the frame and pieces; and this deepening is done with the lacker-varnish, (or with arnotto it self) which being well mixed with the same, all the deep and hollow places and veins of the work are to be touched and deepene with it; by which means the colour is accomplished, and the reflection or a perfect glory.


To LACKER in oil such things as are exposed to the weather.

1. The same method is to be observed here, as in the former, excepting in this, that your priming ought to be whiter than the last, which is effected by mixing a little white-lead which has been ground a long time, with the former gold size.

2. Also your silver uze ought not to be so dry as that of gold, when the leaves are laid on.

To gild carv'd-work in oil, which is not to be exposed to the open air. Melt some size, and put in just so much whiting as will make it of a white colour; do the frame over once with this size. a. Then add more whiting to the size, till it is of a proper thickness; and do it over 3 or 4 times, or more, with this, according as you find the work does require, letting it dry tho roughly between each time.

3. When this is thoroughly dry, rub and smooth the work all over with a piece of fish-skin or Dutch-Rushes, and afterwards water-plane it, with a fine rag, dipp'd in water; rubbing it gently till it is very smooth, and then set it by to dry; and then size it with strong file.

4. Let it stand till it is dry, then lacker over the work twice by a gentle heat, and lay on your gold size, and perform every thing as before directed for laying on leaf-gold.

Ei kommentteja :