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Uniforming Fumed Oak---The Problems Which are Offered in the Differences Found in Woods---Laboratory Discoveries of How to Solve Them By WALTER K. SCHMIDT

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Analytical Chemist

T IS sometimes necessary to point a moral by the recital of a tale, and I am going to introduce this article with a story which I hope will point the moral. Recourse is not had to this story in a spirit of vainglory, but to point out-well, what it

points out will appear further along. The article which follows caught my eye recently, and hoping that it might prove suggestive to some of my critics, I am using it here as a text, for the discussion of a much larger subject:

WHAT TO REMEMBER WHEN CRITICISED

Any man who accepts a position of leadership must expect criticism. Many presidents of clubs lose heart when they hear that Jones, Smith and Brown, when they met at luncheon, said unkind things about the administration. When they hear one croak, they instantly think that the whole club is against its leaders.

the ones who make their slogan, "If a thing is worth doing at all, it is worth doing well." They never claim perfection; they are continually looking for improvements. Such manufacturers have their finishes quoted as authentic in style of finish and color. The others follow. Well, their concern is to produce something "just as good." The salesmen for a manufacturer of this sort have to say, "This is just as good," and as a selling argument "just as good" is certainly not a commendable argument. How much better it would be for the salesmen to be able to say, "This is our fumed oak. Standard-we are proud of it; look at the evenness of color, its beautiful, blended woods. Every piece of wood laid correctly. See how well the boys match the wood; look at the grain, how it is brought out. Stand at any angle that you will, that piece of furniture has the uniformity about it that is always pleasing to the eye."

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WALTER K. SCHMIDT

Booker T. Washington tells a story of a friend of his who once lived near a fashionable hotel in Virginia. "One day a bright idea struck him, and he went to the proprietor of the hotel, and made a bargain to furnish him regularly with a large number of frogs, which were in great demand as a table delicacy. The proprietor asked him how many he could furnish. My friend replied that he felt quite sure that he could furnish him with a cartload, if necessary, once a week. The bargain was concluded. The man was to deliver at the hotel the following day as large a number of frogs as possible. When he appeared, my friend had just six frogs. The proprietor looked at the frogs, and then at my friend. 'Where are the others?' he asked. 'Well, it is this way,' my friend replied, 'for months I had heard those bull frogs in a pond near my house, and they made so much noise that I supposed there were at least a million of them there. When I came to investigate, however, I found there were only six."

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So, when the voice of criticism reaches you, don't be stampeded. Investigate. Dig for the truth. One sunbeam doesn't make the day. Nor does the vulture in the sky shut off the sunshine. It takes more than one man's praise to justify you in carrying out your plans; but it also takes more than six frogs to make a cartload of hoarse-voiced critics.

The Moral Naturally, you have asked, "What has this to do with the finishing department of this paper? Where does it apply?" Follow these lines a bit farther. To begin with, let me say you will have to admit that within the past twelve months the finishing department has awakened. We are doing things differently. We are drying varnish in a kiln; we are applying finishes with a spray; we are using up-to-date methods to produce our colors. Each day we are busy overcoming the deficiencies of the wood. The leaders, and there are always such, are those who are continually looking for information, looking for new methods, better ways, more economical ways to accomplish results; those who have ideals; those who read and then endeavor to improve upon the method suggested; those who are willing to spend a dollar or two, an hour or two, to try out a new scheme, are the leaders. They are

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The pride with which this salesman can recommend his goods is commendable. He has confidence in every section of the factory he represents. It is the result of doing things well.

The writer has had his ideals. The years spent in color work applying chemistry to the production of permanent stain have not been for naught. He has seen ideals of years ago become realities. Methods suggested a decade ago are in daily use today. It has not been a period of years passed without the "croaker," as emulated in the article quoted. Ideas ridiculed, methods belittled, schemes and suggestions disparagingly spoken of, only to find that the loudest croaker is one of those who derived benefit from the articles published in THE FURNITURE MANUFACTURER AND ARTISAN; to find those who will not acknowledge that the writings in this paper have afforded them many good thoughts, methods and ways of procedure that helped to make them more proficient. They go along with the wrong idea and guard secretly the things they know. They may know them, but it is safe to say that in many cases they do not understand the whyfors. It is merely a case of mouth-to-mouth information-doing it because some one told them if they did it that way certain results would be obtained. If called upon for a reason, they did not have it, and yet will not acknowledge the medium that affords them a source of information.

All knowledge is not applicable to each individual case, but there is no telling in this day of achievement when the situation may arise that some particular formula or suggestion will be a very handy bit of reference.

Fumed Oak

From the correspondence that has passed over the desk in the last three months, it is evident that that which most concerns the manufacturer of today is fumed oak-its production, especially the making of uniform shade. The writer has been conducting various experiments with the hope of solving the difficulty daily encountered with this [195]

particular shade, especially as to making uniform the tone. The difficulty is primarily due to the difference in the wood. So much has been written, so many suggestions have been made, and schemes that were promising, that looked feasible, did not work out from a practical and economical standpoint. It is not at all impossible to produce the uniformity, if it were not for the expense and added cost incurred. Bear in mind there are two distinct ways of making fumed oak. One by the fuming process, and the other by the staining process. Neither of these methods will overcome certain deficiencies or tend to uniform the discrepancies due to the differences in the wood. I can only repeat that, to an extent, greater care in selecting and making up the raw stock will greatly assist the finishing room, but even if that precaution be taken, there will still be a large amount of matching to be done by the finisher.

Coat the Pieces First

I have found that greater uniformity can be produced in the fuming box, if the wood or rather the piece of furniture, is coated with a solution of tannic acid and pyrogallic acid, preferably one-half ounce of the former and one ounce of the latter to the gallon of water. I have

found that when the fumes of ammonia have been applied at least four hours, a very even result is obtained, much more so than when fumed without the application of the acids. Where extreme differences of shade are shown, these can be overcome by wetting these places with naphtha which will bring out the discrepancy of shade, and as soon as the naphtha has practically dried out, coat with a very weak solution of brown stain. For this I recommend a solution of bichromate of potash and jet black. Put enough of the black into the bichromate solution to give it the brownish tint. Understand thoroughly that this must be a weak stain. It will be found that when the shellac coat is applied a uniformity is produced which is altogether more satisfactory than when the toning is done in the shellac coat. Where the stain method is employed, a good deal can be done to assist in producing the desired result in the first coat. A solution of two ounces of bichromate to one ounce of carbonate of potash to a gallon of water will produce a first coat. Apply this coat thoroughly and let it stand twenty-four hours. Where a light piece of wood is laid next to a quartered darker piece, say red oak, let the stainer coat the entire piece and then re-coat along the line of the light piece, blending it out. This, when it dries down, and it receives the second coat, will go far to uniform the shade. Again, the application of naphtha will assist. Don't understand that the naphtha has anything to do with the production of the color. It merely helps to bring out the difference in shade, and the man who is doing the blending in that way will shortly know just how heavy to apply the blending coat, and can then dispense with the use of naphtha. Where the blending is done over the second coat of stain, care must be taken not to lift the second coat, so as “to pile it up," and thus produce blotchy work. It will not be necessary to sand these blended coats; the sanding of the first coats will have sufficiently smoothened the work.

For the Finishing of Chairs

In chair factories, where smaller surfaces are presented, the following method may be found expedient for dipping. It is purely a chemical proposition, and by no means a poor way to stain. Make a solution of the two acids recommended, and dip the wood. Let it drain back from a wood drain board. Absolutely no metallic surfaces can be used, which means that the tank itself must be entirely constructed of wood. Immerse the piece and see that it is thoroughly covered. Many times you will find

that the dust from the sanding operation not being thoroughly removed, will keep the stain solution from getting into the wood. In cases like that, a sponge saturated with the stain must be passed over these surfaces thoroughly. Again, sweaty or greasy fingers will keep this stain from penetrating. It is then necessary to pass the sponge over these spots until you are certain that the same amount of stain has been applied as on the balance of the article. After this dipping solution has thoroughly dried, sand very lightly, just enough to remove all the fibers, and dust again. Then immerse the piece in a solution of bichromate of potash, caustic potash, four ounces to the gallon, or three ounces of each to the gallon, if a strong tone is to be obtained. Dissolve four ounces of sulphate of copper in a quart of hot water. Of this copper solution, measure from four to six ounces, preferably in a glass vessel. To this copper solution add an equivalent volume of stronger water of ammonia. When the ammonia is first added, a white precipitate will be formed, which is copper-hydroxide, but which immediately re-dissolves and forms a deep ultra-marine blue-colored solution, with a very strong ammonia odor. This is due to the excess of ammonia, and as long as this excess of This blue solution, then, is added to the chrome potash ammonia is present, the copper will remain in solution.

solution, which amounts to a little better than a gallon, but which must be in thorough solution. That is, the bichromate and the carbonate must have been dissolved. The sudden contact of a carbonate with water has a tendency to so harden the carbonate as to keep it from dissolving, and when it once gets into this form, it is apt to stay in a solid form encrusted on the bottom of the vessel, jug or jar. In that way the resultant shade will be much lighter. When the solution, however, is perfect, stir in the blue copper solution, and continually stir or agitate with the result that a beautiful light green stain will be produced. This, then, is the second coat. Whether it be used with a brush, or whether it be used as a dipping stain, it will form when it comes in contact with the first coat a rich brown. The chemical effect produced is very much lighter than when the same wood is subjected to the fuming box. It will not raise the grain as one would think; it will not attack the glue joints, as is often thought it would. The setting of it has been assured by the care taken in applying the first coat; but if this care has not been taken, it is self-evident that the neglect will be more apparent, because the second coat has had no chemical to work upon, and thus a much lighter color will be presented where the first coat was omitted.

Must Use Brains

In recommending a formula of this kind, the reader must resort a bit of his own ingenuity. He can strengthen or weaken this solution, he can augment the second coat by the addition of anilines, bearing in mind that the mordant which sets the aniline is present in the chemical constituents of the stain, so that there is practically no shade of fumed oak, or brown oak, that cannot be produced with this method. Nor is it necessary that this be used on oak alone. The most beautiful and rich mahoganies, rosewood or cherry can be produced with this method. A decided chemical change is wrought by the application of these chemicals. Understand, if these were all mixed together they would be absolutely useless. The result is entirely due to the placing of the constituent upon which the second series of chemicals work, producing the chemical change which brings forth the color.

I must emphasize that the judging of these colors—or, rather, the results-must not be done until the wood has received its finish, the shellac and wax, bringing out a depth of shade far greater than would be expected.

Where the cost will permit an oil coat before the shellac

is put on, it will revive the wood and give it a richness and mellowness that cannot be produced by the ordinary way of finishing. It must be remembered that in a fumed oak finish it is rarely filled, whereas, most of the other finishes are filled and in that manner a certain amount of oil is received by the wood. But where the wood is not filled, this oil is usually omitted, with the consequence that we lack the depth of transparency which is given by the oil. One has simply to exemplify this by coating a piece of paper with oil, and then shellacking it, or simply

shellacking a piece of paper, and holding both up to a light.

A thoroughness in the finishing department brings profits. There are many corners that can be cut when it is systematized, and where the operators have a thorough acquaintance with the materials at hand, where every handling of the piece counts. A directness of purpose, no rule of thumb methods, records of operations in black and white, so they may be repeated and duplicated at a moment's notice, are a few of the things advocated.

HOW TO DO
TO DO ENAMEL
ENAMEL FINISHING

Careful Preparation of the Wood the First Requisite---Five Coats of Enamel
Necessary to Really Good Work---Some Formulas for the Finishing Material

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By A. ASHMUN KELLY

STRICTLY first-class job will require ten or more coats of paint in all, and less than eight or nine coats is not to be thought of. To begin at the beginning, the first thing to do is to have the surface of the work perfectly smooth, for the beauty of enamel painting consists largely in its perfect smoothness. The first or priming coat is made from pure white lead in oil, some adding just a little French ochre in oil to discolor the white. Thin with raw linseed oil onethird and turpentine two-thirds, with driers a little. Second coat, a composition is made forming a sort of what vehicle painters call rough-stuff, which may be made from white lead and a little plaster, mixed with oil and driers, to form a paste, this being intended to fill out any depressions or uneven places, and when dry is rubbed down to an even and smooth surface. This involves much time in work, but it gives a fine surface for finishing on. The third coat is composed of white lead thinned with turpentine three-fourths and oil one-fourth, using boiled oil. Fourth coat, mix the white lead with five-sixths turpentine and one-sixth white varnish. Fifth coat, mix up white lead and Green Seal French zinc, half of each, thinning with three-fourths turpentine and one-fourth white enamel varnish. For sixth coat, Green Seal French zinc mixed with turpentine three-fourths and enamel varnish one-fourth. Seventh coat, French zinc white mixed with three-fourths enamel varnish and one-fourth turpentine. Eighth coat, color enamel varnish with zinc white, adding just enough turpentine to make the varnish work freely.

Sandpaper smooth between each coat, using hair cloth or very fine glass paper. The first four coats are to be allowed three days at least for drying, and the last four coats to have not less than six days. Rub each coat to a dull finish with flour pumicestone and water. For a high polish finish, follow with rottenstone powder and water. White pine or other sappy wood should be shellacked before priming, using very thin white shellac varnish.

Follow these directions and a beautiful finish will be the result. Some give as a last coat a finishing varnish, which is either left in its gloss, or it is polished to a velvet or satin finish, as desired.

It is not so often that anyone will go to the expense of doing such a fine job as outlined in the foregoing, and five coats is considered to be a very good job on new work, with still fewer coats for old work.

To enamel on cypress, first apply a size of hot thin glue solution, and when this has dried apply a coat of

white lead paint, thinned with three parts raw oil and one part turpentine, with a little drier. If the wood is quite dark, then add a little black to the priming coat, which will be easier to hide with subsequent coats than if left without the darkening. When this is dry you may proceed as directed for ordinary enamel painting. When a dead finish is desired you may apply the glue size to the bare wood, but if the finish is to be glossy, then size on the priming coat. In the latter case, use white glue, adding a little dry zine white. Make the size in this latter case quite thick and apply it hot. When it has become dry, sandpaper it smooth.

Here is another good formula: Prime (white pine or poplar) with white lead thinned with three parts raw oil and one part turpentine. The next three coats mix from zinc white in oil, but which has been "drawn," that is, by washing it out in the zinc its oil has been mostly taken away. You can thin the zinc with turpentine and let it stand until the liquid rises to the top, when it may be drawn off, repeating again, to get more of the oil out. This zinc white is then mixed with damar varnish, which serves as a binder. If the finish is to be in same color, then the first zinc coat is made several shades deeper than the finish is to be, and each coat is then made lighter by degrees, until the fifth coat, which is made of color and varnish. For white finish, zinc white alone is used. Mix with a first-class white varnish. Such varnish is made especially for such work. If the white is to be tinted, then tint it before adding the varnish. The sixth coat consists of this same varnish, tinted to suit, or to make the finish color wanted. Follow with rubbing with pulverized pumicestone and water, after which rub with powdered rottenstone and water; this for an eggshell gloss. Further rubbing with the rottenstone and oil (sweet oil) will give you a fine polish. This is a very good way.

Enamel finish takes the place of the old-time china gloss and is a much superior finish, though involving more work and expense.

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SOME LESSONS IN FURNITURE MAKING

The Details of the Construction of a Shield Back Chair of the Heppelwhite or Sheraton Type---Dimensions Given by Heppelwhite---Features of Chair By C. A. ZUPPANN,

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Of the Union High School, Grand Rapids, Mich.

HE shield backs in chairs which were so popular during the Georgian period were designed by both Heppelwhite and Sheraton. While the shield was used by both great designers, there is a characteristic difference between them which enables one to distinguish them at a glance. The curve of the top rail of the Sheraton shield is always broken with a straight line. In other words, the top rail is made up of two concave curves connected by a straight line at the top. Heppelwhite, on the other hand, invariably used a continuous or unbroken curve. The shield backs of both designers usually had a decorative splat, though sometimes this was omitted and the back caned. This splat was jig-sawed and carved into such conventions as the wheat sheaf, the Prince of Wales plume, vase and others.

Apparently, these chairs are made of

measure on a line drawn perpendicular to a tangent at the point of measurement. Needless to say, this tangent and the perpendicular do not need to be drawn in. Two methods of joining the top rail to the back legs are shown. The one on the left is a plain miter, doweled with two 1/4-inch dowels. The one on the right is a butt joint secured with one 38-inch or -inch dowel. Also two different joints are shown for the lower rail in the back. Each of these is secured by a 3-inch dowel. The student must select the joints desired and make his detail accordingly. All of these joints are used by manufacturers today. The miter for the top rail is, perhaps, the neater joint, but it is also much harder to construct. The butt joint is easier to construct, just as strong, and after the stock is moulded to shape, forming an apparent miter, the joining is scarcely noticeable even upon close examination. Of the joints for the bottom rail, the one on the left is, perhaps, stronger and is very little harder to make than the other.

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C. A. ZUPPANN

a shield supported upon short back posts. It is evident that if such were the method of construction, the back would be weak at the joint thus formed. Shield back chairs are no exception to the general rule which requires that the back legs reach from the floor to the top rail in the back.

The general dimensions for chairs of this style, as given by Heppelwhite himself, are: "Width in front, 20 inches; depth, 17 inches; height of seat frame, 17 inches; total height, about 3 feet, 1 inch." The upholstering brings the seat height to 18 inches. These dimensions are followed approximately in our modern reproductions. In the modern chairs, opinion seems divided as to whether the top rail of the shield should be curved to fit the back or made straight. Some manufacturers use the one method and some the other. All agree, however, on having the shield curved or back fitting from the top to bottom.

That a creditable result may be accomplished in the construction of shield back chairs by many high school boys will be admitted after a trial. It is, however, beyond the ability of a beginner, and unless the pupil shows exceptional aptitude, he should not be encouraged to attempt it. A mastery of the band-saw and jig-saw is necessary, unless the time consumed in construction is of no consequence. A careful boy understanding these machines and the use of bench tools should have no great difficulty.

It is absolutely essential that a full-size detail be made for the working drawing. The accompanying scale drawing may be copied full size or modifications may be made if the ability of the student permits. The curved parts are set off in one-inch squares. By noting where the curves cross the lines forming these squares and transferring this to the full-size detail, under construction, a series of points will be obtained which can be drawn into smooth curves. Care must be taken to get the inside and outside curves of the shield parallel. Draw one curve as desired and lay off the second curve from this. Always

In making the stock bill, the butt joint has been selected for the top rail and the left joint on the detail for the bottom rail. If other joints are used, allowance must be made accordingly. Also the stock for the back legs is considered as made from squared-up stock of sufficient dimensions to enable the student to saw out without blocking. While this

is by far the easier method, it is also wasteful, and if desired a block may be sawed from what would be waste on one side of the leg and added where needed to the other side, thus using stock of smaller dmensions. Of course, this must be done before band-sawing. While this later method would be factory practice and as such should be explained to the pupil, it is not strongly recommendel for school work where safety is the first consideration and where the machine and stock in the simplest form is often all one cares to to allow the pupil for use.

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been taken of glued-up stock. This has just been mentioned in the case of the back legs. The front seat rail offers another illustration. This may be built up in horizontal layers, sawed out and veneered on the face if desired. In this case the blocks band-sawed from front and back would be used as forms or cauls. Of course, these would be padded with blotting paper or something of similar nature before using.

Patterns for the band-sawing should now receive consideration. These patterns may be made of stiff paper, cardboard, or if desired for permanent use, of thin wood. Great care should be taken in laying them out in order that enough stock be left at the joints. The splat and back legs will each need two patterns, though the other band-sawed parts need but one each. The top and bottom rail in the back can be shaped to the curve of the back by hand. These patterns must be carefully smoothed, as a great deal depends upon their accuracy. To transfer the curves from the detail to the pattern stock, use tracing paper and a very soft pencil, first tracing the curve, then reversing upon the stock and going over the lines again, which will, of course, cause a noticeable line to be left on

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the stock. In making the patterns, if a curved back fitting top rail is wanted, a pattern with a 21-inch radius for the arc will be needed. This, however, is not advised, as it considerably complicates the work.

The actual construction may now be commenced. After all stock is gotten out to the rough size given in the stock bill, which allows one inch in length and 1/4-inch in width for finishing, the patterns should be laid out on the different parts with pencil, carefully tracing around each pattern. Band-saw on the outside of these lines. If care is taken not to run the saw out of the stock, but to leave the waste attached, it will be found easier for the student to saw out the adjoining surface, as he will thus have a solid foundation or cradle for the stock and also will have the marked surface in its proper position. It will be found far better, also, to err by leaving too much stock than by sawing inside of the lines. The inside curves of the splat should be jig-sawed before the band-sawing is done on this piece. After the jig-sawing, the stock should be placed on edge and the curve of the back carefully

sawed. The waste stock should now be nailed back in its original position and the remaining pattern band-sawed to shape. The bead is band-sawed on the splat and not glued on afterward.

When all band-sawing has been finished, the pieces should be planed and spoke shaved to shape, regulating with file when necessary. The bead should be shaped with a chisel. The joints in the back should be carefully trimmed out with a chisel. Mark off the mortises in the top and bottom rail in back with the marking gauge and cut with a 1/4-inch chisel. The tenons on the splat may be marked with a knife at this time, but a safer method would be to mark them after the rest of the back has been temporarily assembled, at which time the length of the tenon can be determined with more accuracy.

When all parts are finished, lay off the dowel holes in the rails and bore 3/8-inch holes, as indicated. Using dowel markers as described in a previous issue of this magazine, mark off the holes in the legs-front and backand bore these for dowels. The seat rails fit flush with the front legs, but the side seat rails are set in 1/8-inch on the back leg. It is presupposed that in sawing, the angles on the ends of the rails have been accurately cut. Fit the chair together and inspect the work. Mark off and cut the tenons on the splat. Fit the stretchers and bore for dowels. The angles at which to saw the stretchers are gotten from the stretcher plan and the side view. The side stretchers are cut at both a horizontal and a vertical angle. The middle stretcher at a horizontal angle only.

The seat rails are now to be rabbitted 1/2-inch by -inch for the upholstery. This can be done by gauging deep and cutting out with a chisel or can be done very easily on the shaper. Round the shield to the section shown and carve out back post where it runs into the shield. The shape is shown in the detail by the dotted line. Notch out front posts for upholstery, carrying the line of the rabbitt in the rails entirely around the front posts. Saw out corner blocks, being sure that the correct angle is secured.

Glue up the front legs and front seat rail, also the entire back. In clamping these parts together, great care must be taken, as the curved rails will tend to spring if clamped too tight, thus opening the joints and spoiling the entire job. When the glue has set, the rest of the chair may be assembled and corner blocks glued and screwed in place. Go over all parts, scraping off any excess glue and then sandpaper smooth first with medium, then with fine sandpaper. Do not sandpaper across grain at any place. After all marks are out and a good surface is obtained, the finishing may be undertaken.

A stain suitable for this design may be bought mixed and ready for use from stain manufacturers advertising in this magazine. Usually these prepared stains are made with spirits in some form as the medium. These same firms also sell stain in powder form, which can be dissolved by the purchaser in water or spirits, as the nature of the powder requires. The acid anilines are "water stains," and will be found to produce excellent results. Purchase mahogany brown and mahogany red. Then dissolve a small quantity of each in separate vessels of water. The proportions will be given by the company from which the powder is purchased. Mix together in a third vessel a quantity of the dissolved brown and red, adding of one or the other until the desired shade of mahogany is produced. Keep an accurate account of the quantities used for future reference.

Coat some test strips with the stain and when dry finish with shellac. If the finished shade is not just what is desired, change the proportions of red and brown in the

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