section ii
Of japan grounds.
The proper japan grounds are either fiich as are formed by the varnifli and oolour, where the whole is to remain of one fimple colour; or by the varnilh either coloured, or without colour, on which fojne painting or other decoration is afterwards to be laid. It is necefiary, however, before I proceed to fpeak of the particular grounds, to fhew the manner of laying on the priming or undercoat, where any fuch is ufed.
This priming is of the fame nature with that called clear coating (or vulgarly clear coaling) praftifed erroneoufly by the houfe painters; and confifts only in laying on and
drying in the moil even manner» a compofi- tion of fize and whiting. The common fize has been generally ufed for this purpofe: but where the work is of a nicer kind, it is better to employ the. glover’s or the parchment fize j and if a third of ifinglafs be added, it will be (till better; and if not laid on too thick, much lefs liable to peel and crack. The work fhould be prepared for this priming, by being well fmoothed with the fifh-fkin, or glafs (haver; and, being made thoroughly clean, fhould be brufhed over once or twice with hot fize, diluted with two thirds of water, if it be of the common ftneogth. The priming fhould then be laid on with a brufh as even as poffible ; and fhould be formed of a fize, whofe confidence is betwixt the common kind and glue, mixt with as much whiting as will give it a Sufficient body of colour to hide the furfacc of whatever it is laid upon, but not more.
If the Surface be very even, on which the priming is ufod, two coats of it, hid on in this manner, will be fuffident: but if, on trial with a fine rag wet, it will not receive a proper water poliih, on account of any inequalities not Sufficiently filled up and covered, two or more coats mud be given it: and whether a greater or lefs number be ufed, the work fhould be fmoothed, after the lad coat butone is dry, by rubbing it with the Dutch rufhes. When the lad coat is dry, the water polifh fhould be given, by paffing over every part of it with a fine rag gently moidned» till the whole appear perfectly plain and even. The priming will then be completed, and the work ready to receive die painting, or coloured varniih: the red of the proceedings being the lame in this cafe as where no priming is uled.
Of common grounds of v which are to be painted .
Where wood or leather is to be japanned, and no priming is uled, the bed preparation is, to lay two or three coats of coarle varniih corn« poled in the following manner. *
** Take of rectified Ipirit of wine one pint, “ and of coarfe feed-lac and refin each two ** ounces. Difiblve the leed-lac and refin in “ the fpirit: and then drain off the varniih.”
This varniih, as well as all others formed of ipirit of wine, mud be laid on in a warm place; and, if it can be eonveniendy managed, the piece of work to be varnilhed Ihould be made warm likewife : and for the fame realon all dampnefs Ihould be avoided; for either cold or moidure chill this kind of Varniih; and prevent its taking proper hold of the fub- dance on which it is laid. -
When the work is lo prepared, or by the priming with the compofition of fize and whiting above defcribed, the proper japan ground mud be laid on: which is much the bed formed of fhell-lac varniih, and the colour defired; if white be not in quedion, vtfhich demands a peculiar treatment, as 1 lhail *below explain; or great brightnefs be not required, when alfo other means muft be permed. The compofition of the fhell-lac var- mfh, with the reafons why it is preferable to all other kinds as a vehicle for colours, I have before given p. 177 j and therefore need not repeat them nere; though the advantage of this method over all others, where great brightnefs is not demanded, and the durablenefs is of confequence, can fcarcely be too much urged. .
The colours ufed with the fhell-lac varnifh may be, any pigments whatever which give the teint of the ground defired; and they may be miixt together to form browns or any compound colours: but with refpeft to fuch as require peculiar methods for the producing them of the firft degree of brightnefs, I fhall particularize them below.
The colours for grounds may otherwife be mixed with the white varnifhes formed in oil of turpentine j of which the preparation is given p. 179—213 and 214 : butthefe varnifhes have no advantages over the fhell-lac but in their whitenefs, that preferves the brightnefs of the colours ; and they are at the fame time greatly inferior in hardnefs to it.
As metals never require to be under coated with whiting, they may be treated in the fame manner as wood or leather when the under- * coat is omitted, except in the inftances particularly fpoken of below.
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Of •white jafan grornds.
The forming a ground per&CUy white, and of the firft degree of hardnefs, remains hitherto a defideratum, or matter fought for, in the art of japanning. As- there are no Jubilances which form a very hard yarnHh, but what have too much colour not to deprave the. whitenefe* when laid on of a due thicknefs over the work.
The neareft approach, however to a perfect white vamifh, already known, is made by the following compofkion.
“ Take flake white, or white lead, wafhed “ over and ground up with a fixth of its ** weight of ftarch, and then dried} and “ temper it, properly for fpreading, with the 44 maftic vamifh prepared as in p. 179, or “ compound them with the gum am mi, ac- 44 cording to the directions given in die fame 44 page.” Lay foefe on the body to be japanned, prepared either with or without foe undercoat of whiting, in foe manner as above ordered : and then vamifh over k with five or fix coats of the following varnifh.
“ Provide any quantity of foe beft feed “ lac } and pick out of it all the cleaceft and <c whiteft grains} referving the mote coloured 44 and fouler parts for the coarfer vamifhes* “ fuch as that above mentioned for priming 44 or preparing wood or leather. Take of this 44 pickt l'ecd-lac two ounces; and of gum animi
“ three
“ three ounces; and diflolve them, being “ previoufly reduced to a grofs powder, in a“ bout a quart of fpirit of wine; and’Strain off “ the clear vamilh.” •
The feed-lac will yet give a flight tinge to this composition; but cannot be omitted, where the varniSh is wanted to be hard: though, where a Softer will anfwer the end, the proportion may be diminished; and a little crude turpentine added to the gum animi to take off the britdenefs.
A very good varniSh, free intirely from all brittleneSs, may be formed by diSTolving as much gum animi, as the oil will take, in old nut or poppy oil; which mult be made to boil gently, when the gum is put into it. The ground of white colour itfelf may be laid on in this varniSh; and then a coat or two of it may be put over the ground: but it muft be well diluted with oil of turpentine when it is uied. This, though free from britdenefs, is, neverthelefs, liable to fuffer by being indents ' ed or broiled by any flight Strokes; and it will not well bear any polish, but may be brought to a very fmooth Surface without, if it be judi- cioufly managed in the laying it on. It likewife Somewhat tedious in drying, and will require Some time where feveral coats are laid on; as the laSt ought not to contain much oil of turpentine. .
Of blue japan grounds.
Blue japan grounds iqay be forthed of* bright Pruffian blue ; or of verditer glazed Over by Pruffian blue ; or of ftnalt. The colour may be beft mixed with fhell-lac vami/h; and brought to a polifhing ftate by five or fix! coats of vamifh of feed-lac j but the vamifh , neverthelefs, will fbmewhat injure the colour, by giving to a trae blue a caft of green ; and fouling in fbme degree a warm blue, by the yellow it contains. Where, therefore, a bright blue is required, and a lefs degree of hardnefs can be difpenfed with, the method before di- reded, in the cafe of white grounds, mull be perfued.
Of red japan grounds.
For a fcarlet japan ground, vermilion may be ufed: but the vermilion has a glaring efi* fed, that renders it much lefs beautiful than the crimfori produced by glazing it over with carmine or fine lake; or even with role pink, which has a very good effed ufed for this purpofe. For a very bright crimfon, neverthelefs, inftead of glazing with carmine, the Indian lake fhould be ufed, difi- folved in the fpirit of which the vamifh is compounded (which it readily admits of when good): and, in this cafe, inflead of glazing with the fhell-lac vamifh, the upper of polifhing coats need only be ufed; as they will equally receive and convey the tinge of the Indian lake, which may be actually dif- lblved by fpirit of wine: and this will be found a much cheaper method than the uling carmine. If, neverthelefs, the higheft degree of brightnefs be required, the white varniflics muft be uled.
Of yellow) japan grounds.
For bright yellow grounds, the King’s yellow, or the turpeth mineral, Could be employed, either alone or mixed with fine Dutch pink: and the effect may be ftill more heightened by diflolving powdered turmeric root in the lpirit of wine of which the upper or policing coat is madej which fpirit of wine muil be ftrained from off the dregs, before the feed-lac be added to it to form the varnifh.
The feed-lac varnifh is not equally injurious here, and with greens, as in the cafe of other colours} becaufe, being only tinged with a reddilh yellow, it is little more than an addition to the force of the colours.
Yellow grounds may be likewife formed of the Dutch pink onlyj which, when good, will not be wanting in brightnefs, though extremely cheap.
Of green japan grounds.
Green grounds may be produced by mixing' the King’s yellow and bright Pruffian blue 5 or rather, the turpeth mineral and Pruffian blue: and a cheap, but fouler kind, by verdigrile with a little of the above mentioned yellows, or Dutch pink. But where a very bright green is wanted, the chryltals of verdigrife, (called dijiilled verdigrife) ffiould be employed ; and to heighten the effedt, they ffiould be laid on a ground of leaf gold, which renders the colour extremely brillant and pleafing. They may any of them be ufed fuccefs- fully with good feed-lac varniffi, for the rea- fon before given: but will be ftill brighter with the white varniffi.
Of orange coloured japan .
- Orange coloured japan grounds may be formed, by mixing vermilion, or red lead, with King’s yellow, or Dutch pink j or the orange lake, prepared as diredted in p. 111, will make a brighter orange ground than can be produced by any mixture. -
Of purple japan grounds.
Purple japan grounds may be produced by mixture of lake, -and Pruffian blue: or a fouler kind, by vermilion and Pruffian blue.
They may be treated as the reft, with refpedt to the varnilh. •
Of black japan grounds, to be produced without
beat.
Black grounds may be formed by either ivory-black, or lamp-black: but the former is preferable; where it is perfectly good.
Thefe may be always laid on with the Ihell* lac varnilh: and have their upper or polilhing coats of common feed-lac varnilh j as the tinge or foulnels of the varnilh can be here no injury.
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Of common black japan grounds on iron or copper, produced by means of heat.
For forming the common black japan grounds by means of heat, the piece of work to be japanned muft be painted over with drying oil: and when it is of a moderate drynels, muft be put into a ftove of fuch degree of heat, as will change the oil black, without burning it fo as to deftroy or weaken its tenacity. The ftove Ihould hot, be too hot when the work is put into it, nor the heat increafed too faft; either of which errors would make it blifter: but the flower the heat is augmented, and the longer it is continued, provided it be reftrained within the due degree, the harder will be the coat of japan. This kind of varnilh requires no polilh, having received, when properly managed, a diffident one from the heat.
• Of the fine tortoife Jkell japan produced
by meaia of .
The beft kind of tortoife (hell ground produced by heat is not lefs valuable for its great hardnefs, and enduring to be made hotter than boiling water without damage, than for its beautiful appearance. It is to be made by means of a varnifh prepared in the following manner. -
“ Take of good linfeed oil one gallon, and “ of umbre half a pound. Boil them toge- “ ther till the oil become very brown and “ thick: (train it then through a coarfe cloth; “ and fet it again to boil; in which ftateit “ muft be continued till it acquire a pitchy “ confiftence, when it will be fit for ufe.” '
Having prepared thus the varnifti, clean well the iron or copper-plate, or other piece which is to be japanned; and then lay vermilion tempered with (hell-lac varnifh, or with drying oil diluted with oil of turpentine very thinly, on the places intended to imitate the more tranfparent parts of the tortoife (hell. When thé vermilion is dry, brulh over the whole with the black varnifh tempered to a due confidence with Oil of turpentine; and when it is fet and firm, put the work into a ftove, where it may undergo a very ftrong heat, and muft be continued a confidence . . „ time, if even three weeks or a month, it will be the better.
This was given amongft other receipts by Kunkel; but appears to have been negle&ed till it was revival with great fuccefs in the Birmingham manufactures, where it was not only the ground of lhuff boxes, dreffing boxes, and other fuch lefler pieces, but of thole beautiful tea waiters, which have been fo juftly e- Iteemed and admired in feveral parts of Europe where they have been fent. This ground may be decorated with painting and gilding, in the lame manner as any other varnilhed furface, which had belt be done after the ground has been duly hardened by the hot ftove 2 but it is well to give a fecond annealing with a more gentle heat after it is finilhed.