Rakennetaan urut

How To Build A Small Organ

Tämä on kopio ensimmäisestä Internetistä löytämästäni urkujenrakennusartikkelista. Vuodelta 1884 peräisin oleva kirjoitus neuvoo mm. ilmalaatikon rakentamisen 1600-luvun tyyliin yhdestä puusta, mikä on osoittautunut käytännössä hyvin araksi rakenteeksi. En kehottaisi ketään alkamaan rakentamista tämän perusteella, siihen on olemassa paljon parempiakin oppaita, esimerkiksi tämän sivun Kirjallisuutta-osiossa. Tällä kirjoituksella on kuitenkin oma kuriositeetillinen arvonsa, ja siksi se saakoon paikan täällä, koska alkuperäinen nettisivu on jo kadonnut bittiavaruuteen.

These are articles reprinted from Work Illustrated, from 1884. They are quite optimistic, and judging by the response from some readers, not unjustifiably so.

I--General Principles of Construction -- Materials for the Pipes -- Method of Making the Stopped Tenor C Pipe.

If the manufacture of an article, ornamental or otherwise, that can be seen only, affords considerable pleasure to the maker, how much greater must be the gratification and self-satisfaction enjoyed by the amateur, who, after long hours of anxious care and labour has produced an instrument that can be heard as well as seen, and therefore appeals to two out of the five senses instead of but one.
 
Construction, or in other words, the making of the various component parts of any article, bit by bit, and putting them together, may be taken to be the
summum bonum of most amateurs. The accomplishment of the object now in view, inasmuch as it involves plenty of making as far as the separate parts are concerned, and plenty of careful putting together; affords an excellent exercise of ingenuity and patience to any who may be enamoured of mechanical work, so without taking up their time and occupying valuable space with preliminary remarks on the history and progress of organ-building, which they may gather for themselves from any good encyclopaedia, such as "Beeton's Illustrated Encyclopaedia of Universal Information," I will at once enter upon my subject and proceed to sketch out for their information the processes necessary in making a small organ.
 
By a "small organ" I do not mean such an instrument as would be placed in a church or school-room; I mean such a miniature organ as will discourse sweet, quiet music in a drawing-room or library, and which may serve as a pleasing accompaniment to the voice of a singer. If some little contempt should be expressed for so tiny an instrument, as a mere "kist o' whistles," let it be remembered that I write not so much for more fortunate amateurs who have gained experience in carpentry, and are possessed of the means to supply themselves with what they will, but for young carpenters with slender purses, and that I desire to avoid taxing severely either the ability of the first or the
capacity of the second.

I shall assume that the would-be organ-builder has access to a convenient workshop, with a bench and tools; and that he is handy with the plane. But I shall not assume more than this; I shall not even take it for granted that he is musical. James Watt built a very remarkable organ, though he was destitute of musical talent. Above all, I shall not assume that he has the command of considerable sums of money; and in all my directions I shall keep economy strictly in view.

First, then, let us clearly see our task before us. The simplest organ consists of a wide, shallow box, called a wind-chest, with a top called a sound-board, divided internally into compartments called grooves or channels, and filled with air by a pair of bellows. The wind-chest is supported horizontally above the bellows by corner-posts and cross-rails making up the "building-frame." On the top of the sound-board the pipes are planted; and each pipe is made to speak or sound at pleasure (when the bellows are blown) by opening a valve in the wind-chest connected with a key or note in the finger-board. So that if there are fifty keys or notes in the finger-board, then there will be fifty pipes (at fewest) in the organ; and as every pipe must have its channel and its valve, there will be fifty channels and valves in the sound-board and wind-chest. But I shall show that the fifty channels and valves may supply ten times fifty pipes, if an organ with numerous pipes be desired.
 
I propose that the amateur organ-builder shall commence operations by making the pipes. I do this because the first outlay for the requisite wood need not be great, and because he will be much encouraged at the outset of his undertaking if he find himself successful with the essentially musical part of it. Our pipes will be partly of the kind called "Stopped Diapason," and partly of the kind called "Clarabella." The whole of them will be made of half-inch pine boards, which should be very dry and clean, i.e., free from knots; and we shall require a few lengths of harder wood, such as mahogany or oak, in scantlings of about two inches square and a few feet long, or in short pieces. The odds and ends of a cabinet-maker's shop often serve useful purposes in pipe-making.
 
Let us begin by making the stopped pipe called Tenor C (Fig. 1); it will serve as a sample of all the other stopped pipes, whether larger or smaller. Take a piece of the scantling, say 2 inches square, and 2 or 3 feet long. Dress down one side with the jack-plane until the piece is 1 3/4 inches wide by 2 inches deep; smooth the whole piece nicely with the "jointer," taking care to keep the angles perfectly square. Cut off a piece 3 inches long for the "block" (Fig. 2, B) of the pipe, and another 4 inches long for the "stopper" (A). Across the narrower side of the block, and three-quarters of an inch from one end, make a deep saw-cut; about half an inch from this saw-cut make another, and take out the intervening wood with a chisel. The gap thus made, called the "throat" (C), should be 1 1/2 inches in depth. Now prepare the two sides of the pipe, cut the boards somewhat more than a inches wide, and about 2 feet 4 inches long; dress them nicely, and glue them to the two wider sides of the block; take care that the joint is good, and allow the whole to dry. When it is so, dress the edges of these boards with the jointer so that the glued-in block shall be perfectly level with them. Then prepare the back and front boards, observing that while the back board must be of the full length of the pipe, the front board may just overlap the inner edge of the block. Smear over with thin glue the whole interior surface of all the four boards; then apply the back and front boards, and bind them round with strong twine, using all your strength to draw it tight, and winding the string round a little roller of wood to avoid cutting your hands. Allow the whole to dry for a night at least. If, on removing the twine, and dressing the pipe over with a fine plane, the joints are perfectly close and good, the maker may hope for a pure tone from the pipe.

To enable it to give a tone at all, however, it must now be "voiced." With a pocket-knife (which is much used in organ-building) and a sharp chisel form the sloping or chamfer in the front board shown at F in the cut (Figs. 2 and 3). Then, guiding ) your knife by means of a square, cut across the chamfered part to form the mouth of the pipe. This mouth, in a stopped pipe, is, in height, commonly about one-third of the width of the pipe internally ; in the present pipe it will therefore be somewhat more than half an inch in height. With the chisel bring the chamfer of the mouth to a neat but not sharp edge. Prepare the "cap" (see D, Figs. 2 and 3) by taking a piece of mahogany, or other hard wood of the requisite size, and cutting a hollow in it with a chisel, deep at G, and diminishing to nothing at H.

When fitted to the pipe the upper edge of the block must just show(say the sixteenth of an inch) above the upper edge of the cap. Between the block and cap a "wind-way" is made by carefully filing the cap at H before it is fixed on. This wind-way should present a cleft not much wider than the thickness of a common playing-card. Fix the cap on by two sprigs or screws (not more), running into the edges of the side boards.

Next take the piece of wood, 4 inches long, which was reserved for the stopper. Fashion it into a convenient shape, as in the cut; cover its lower part with soft white leather (the thinner the better, if the stopper fits well), and insert it carefully in the top of the pipe, using a little soap, or tallow, or black-lead, to facilitate its sliding easily but closely within it.

All that now remains is to bore a hole with the brace-and-bit in the bottom of the block, and insert the foot (E). If the amateur has no lathe he may plane the foot up, and make it as round as he can; it should be 5 or 6 inches long, and the hole through the middle may be bored with a large gimlet, or the brace-and-bit. If the wood be turned continually as the hole is bored, it will probably be central. Burn the hole afterwards with a red-hot iron.

Now, on blowing through the foot, the labours of the amateur will be rewarded by a good musical note. Of the quality of the note, and how to modify its power and vary its tone, I shall treat hereafter. Enough, at present, if it is seen that the note is produced by the edge of the lip (F) cutting or dividing the sheet of wind thrown against it from the cleft between the block and cap; and, therefore, that a nice adaptation of these several parts is essential to success. (See Fig. 3.) Some builders file little nicks in the front of the block; and sometimes in the edge of the cap, to facilitate the passage of the sheet of wind against the lip or edge of the mouth; others omit these nicks. The stopper enables us to shorten our pipes; thus, an open pipe producing: the note Tenor C must be 4 feet in length, while our stopped Tenor C is but 2 feet or thereabout. Into the acoustical reasons of this I Cannot now enter. But if the pipe gives a husky, bad note, examine the stopper, and see that in inserting it you have not opened one of the seams. An aperture no larger than a pin-hole will spoil the tone of a pipe. Hence the internal sizing with glue.

Of course this one pipe is an experiment. In my next paper I will proceed to show how time and material may be economised in making the whole set of pipes, with their varying sizes and lengths. After that I shall direct the maker's attention to the bellows and building-frame, proceeding thence to the important wind-chest.

Before I conclude, however, a few words of advice are necessary, and I cannot impress too strongly upon the amateur the necessity of paying strict attention to rvhat I am about to say, as it will greatly facilitate his labours. The dimensions of the pipe that we have been considering have been given in every particular, and the shape of the pipe and the relations of its various parts have been set forth in the figures with which this article is illustrated. From these let the amateur construct working drawings to scale. It will help him to master the construction of the pipe before he applies a single tool to the wood of which it is to be made; but, by effecting this, will abridge the time taken in making the pipe by about one half.

II -- The Complete Set of Pipes.--Diapason or Scale.--Setting out Pipes.--Bourdon Pipes.-- The Bellows, and how to make them.

It will be convenient to begin this chapter by describing the complete set of pipes which we shall have to make, with the names of the notes to which they belong in the musical scale.

Let it be understood, then, that we are about to make a set of pipes extending upwards from the note called "CC" (or "double C") to "F in alto:" in other words, we are about to make fifty-four pipes, of which the lowest, or deepest in sound, is CC, and the highest, or shrillest, is F. In this set of pipes, four complete octaves, with six additional notes, are comprised ; and the pipe which was described in the first paper, and which we are now supposed to have made successfully, is the first pipe of the second octave, and is called "Tenor C,'' or simply C. It is also called "4-feet C," because an open pipe must have a length of 4 feet in order to produce a note of the same pitch. The first note of the third octave is called " Middle C," or "2-feet C;" while the lowest note, or CC, is often known as " 8-feet C." The annexed table in Fig. 5 gives us part of the scale :-

In the table, "s" signifies " sharp," and the pipes so indicated will correspond with the black keys of the pianoforte. "Gamut G" and "fiddle G" are convenient names by which those notes may be distinguished.

And now to our carpentring again. It will already have been perceived that an obvious and interesting rule or law is laid down by the terms 8 ft., 4 ft., and 2 ft., as applied to the first notes of the three lower octaves; and the reader has probably arrived at the correct conclusion that the other dimensions of the pipes will be regulated by the same easy proportion. In truth, each octave of pipes will be as nearly as possible half the length, and half the size in all respects, of the octave of pipes immediately below it; or double the length, and double the size, of the octave of pipes immediately above it.

Thus, if we made Tenor C 2 feet long, 2 inches deep (internal measurement), and 1 3/4 inch wide, with a mouth 1/2 an inch high, then CC will be 4 feet long, 4 inches deep, 36 inches wide, with a mouth 1 inch high; and Middle C will be 1 foot in length, 1 inch in depth, and 7/8 of an inch in width, with a mouth 1/4 of an inch in height. We have, then, an easy method of obtaining the dimensions of all our pipes. Take a large sheet of paper (see Fig 4); near one edge draw a long straight line (or make a straight crease); at one end of this line draw a perpendicular to it of 4 inches in length; at the other end draw another perpendicular 2 inches in length; join these by a straight line passing through their extremities. Divide the space between the two perpendiculars into 12 equal portions, and draw perpendiculars parallel to the first. Then these 12 perpendicular lines will give you the lengths of all the pipes of the first octave in feet and inches, and all the depths in inches and parts of an inch; and it is evident that you may get all the widths also by drawing another line through the perpendiculars from 3 1/2 inches at to 1 3/4 inch at Tenor C, as shown in the figure.

From this "Diapason," or Scale, the amateur artisan may cut out all his material, and see his work clearly before him. It will be well to make the lowest, or first, octave before the others, because the odds and ends of board left after finishing these will work up in the smaller pipes. Each pipe will be made precisely as Tenor C was made; but the four or five larger pipes will be all the better if put together with 3/4-inch boards; and material may be saved by making the stoppers out of 1 1/2 inch board, fixing a strong handle or peg in each. Do not glue in the feet, however, until a subsequent stage of the proceedings.

It is evident that the same " Diapason," or Scale, will serve for the Tenor Octave, by taking half the dimensions marked thereon; and it may be remarked It may be remarked that by taking .double the dimensions we should be enabled to set out the large pipes called " Bourdon," if we were concerned with them. But it will generally be found convenient to draw a new scale for the other octaves; and no harm will be done if, in drawing this, a somewhat gentle diminution be allowed in the width and depth of the pipes as we rise upwards. Thus, Middle C may be allowed a clear inch, or rather more, of width, with 1 1/2 inch of depth.

Of the upper pipes we shall say nothing at present, because you will do well to finish the two lower octaves (24 notes) first, and then to make the bellows. To the bellows-making let us now proceed, then; and in the outset let me remark that you may prepare yourself for a rough but not difficult operation. We shall require a piece of good inch board, about Io feet or 12 feet long and 14 or 15 inches wide--pine is the best, but as pine of this width cannot be had, the width must be obtained by clamping two pieces of stuff 7 1/2 inches wide, together. We shall also want some "mill-boards," as used by bookbinders for the sides of ordinary books, and two or three skins of white sheep leather, which may be bought at the curriers' or at a shoemaker's. This leather cannot be too supple, but it may be reasonably stout; the druggists keep an excellent quality of it for the purpose of making adhesive plasters, but their prices are somewhat high. "Wash-leather" will not answer the purpose. Of course, if an organ-builder will spare a few skins, it is impossible to get wrong. I propose that our bellows shall be 2 feet 6 inches in length, by 14 inches or more (according to the size of your boards) in width. A glance at Fig. 6 will show you that a beginning must be made by cutting out and planing three boards, AA, BE, and three boards, AA, BE, and cc; AA belongs to the "feeder;" cc is called the upper board; and BB we will call the middle board. B must be 3 feet in length, because its ends must rest on the organ-frame; A and c will be 2 feet 6 inches each. Upon B fix four bars or pieces of inch stuff very strongly, with screws and glue, to form a shallow box 2 feet 6 inches long (outside measurement) and as wide as the board will allow, with a depth of 3 inches (DD, Fig. 6). Bore a number of holes in B with your largest centrebit; eighteen holes will not be too many if the bit is 1 inch in gauge. Over each of these holes place a flap or valve, made by gluing together two thicknesses of the white leather; each flap or valve must play easily upon the hole by allowing a single thickness only of the leather to act as hinge ; but take care that no valve plays so freely as to be completely thrown back or over. Prepare a similar series of holes, with valves, in the board AA for the feeder; and connect AA with the under side of BE by a strong hinge made of stout leather, or by several 'hinges made of pieces of leather strap nailed and glued to each board.

It is now evident that to complete the feeder, as shown in the figure, two sides and one end will be required, so arranged as to expand or contract at pleasure. These are called "ribs," and in ordinary organs are made of thin wooden boards, connected together by hinges of the white leather. In the very small bellows, however, which we are now making, the bookbinders' mill-boards may answer the purpose sufficiently well, and may save much laborious planing. From a mill-board of the requisite size, cut out two side ribs and the end rib,shaped as in Figs 7,8.

Run a knife along the lines A B, C D, cutting the boards about half through, to form a hinge, and glue a long strip of leather upon the hinge so formed. Connect these three ribs with the feeder-board AA (Fig. 6) by means of similar long strips of leather about 2 inches wide; and when the glue has had time to"set," connect the upper edges of the ribs with the underside of BB (Fig. 6) in a similar manner. Open and close the feeder cautiously in doing this, that you insure the neat and flat folding of the ribs. Lastly, close up the corners by gluing on "gusset-pieces" (Fig. 9) of supple leather, amply large enough to allow the feeder its full expansion; and glue wide strips of leather over the main hinge of the feeder and over the junction of the ribs with the main hinge. All this gluing on of leather--an unpleasant and dirty business--will be greatly facilitated by using a bit of sponge, moistenedwith warm water, to press down the various strips into their places. The moistening aids the adhesion of the leather, while it cleans the work, leaving all neat and white. If the feeder is successful it should now work on its hinge freely and pleasantly, without any creaking or any stiffness ; and it should suck in the air through its own valves, and expel it through the valves in B, with entire facility.

The upper part, or reservoir, of the bellows is made precisely as the feeder was made, except that the side ribs will be rectangular, as in Fig. 10. Glue the leather hinges of the first, or lower, set (see Fig. 6) to the upper edges of the box formed on BE ; to the other hinge of these ribs attach a light wooden frame made of 1/2 inch stuff; to this light frame, again, attach the leather hinge of the second or upper set of ribs, to which, again (but not just yet) the upper board CC will be connected. Or it maybe found less troublesome to connect both sets of ribs first of all with the light wooden frame by means of inside strips of calico glued to each, reserving your outside strips of leather for the final putting together, when the gusset-pieces are worked in. But, at any rate, take care (as in the case of the feeder) that the ribs and frame lie closely and flatly when folded down.

In the upper board cc (Fig. 6), an escape-valve must be prepared. Cut a rectangular aperture in it 5 inches by 3 inches; cover this aperture by a valve made of perfectly level board, 6 inches by 4 inches, faced with white leather, with the rough side outermost. Fix the valve by a leather hinge on the inside of cc, so as to open inwards; and on the outside fix a strong spring (or two) of iron wire, so arranged as to keep the valve shut. Nail the end of a string to the middle of the board BE, and bring the other end through a hole in the valve, tying a knot so that the string may be tight, and may pull the valve open, when the reservoir is quite full of air. If the reservoir rises about Io inches, which is amply sufficient, then the string may be nine inches in length, or somewhat less. The frames, or counterbalances (K, L, M, N, Fig. 11), are for the purpose of making the ribs of the reservoir expand equally and properly. They may be made of any tough wood, with screws at the jointed points. See that each screw " bites " in one arm only, passing clear through the other; and use :allow in putting these screws in, with a little black-lead where the arms rub against each other. It will be well to strengthen the upper board c by screwing two ledges of inch stuff, IB inch deep, across the top, near the ends.

 I am far from denying that the bellows-making is a rough and rather distasteful business; but there is no difficulty in it which patience will not readily surmount. Let it be remembered that perfect air-tightness must be secured in every part; cover the corners of the box on B with leather, and allow no crevice whatever to remain unstopped. Leaky bellows not only waste the wind, but give rise to unpleasant hissings which do not improve the music.

 III. The Wind-Chest and Sound-Board.

The amateur organ-builder is about to enter now upon the most arduous, but at the same time the most interesting and agreeable, part of his undertaking --namely, the making of the wind-chest with its belongings.

Let us first gain a general idea of the wind-chest and sound-board. We are about to make a close oblong box, divided internally by fifty-three transverse partitions into fifty-four transverse grooves or channels, perfectly air-tight, and perfectly separated from each other. On the upper side of this box holes will be bored down into each channel, and upon every such hole (or near it) a pipe will be planted ; on the under side of the box each channel will be closed in by a valve called a pallet, which will be kept shut by 3 spring, but which can be easily opened by a leverage connecting it with its key or note on the finger-board. These pallets will be inclosed in an air-tight box underlying the first box, and supplied with wind from the bellows through the wind-trunk.

An examination of the three woodcuts, Nos. I2, 13, and 14, together with the sketch of the completed organ, Fig. to, which will accompany the next and concluding paper, will greatly facilitate the explanations which are to follow, and the whole structure may be comprehended by a careful study of the details here indicated. In Fig. 8 AA is the sound-board, containing the channels; B B is the wind-chest--the board which shuts in its front being removed-- containing the pallets; one of which is shown at C as pulled open in order that the wind may rush into its channel, and through the hole at the top into the pipe D. Fig.13 represents a cross section of Fig. 12: A, as before, is the sound-board; B, the wind-chest; c, the pull-down; the pallet is marked E; the spring F ; G is the plate through which the pull-downs work air-tightly. Fig. 14 is a side view of the "action," in which c is the pull-down of the pallet, attached to the end of a lever called a back-fall, which works freely on a pivot or pin at M; K is one of the keys in the fingerboard; L is a wooden rod called a sticker, having a wire at each end, which passes loosely through holes in the key and back-fall. It is evident that the pressure of a finger on K, as indicated by the arrow, will throw up the end N of the back-fall, and depress C with its pallet.

And now to construct all this simple but neat mechanism. First, the sound-board I advise you to make this out of a piece of solid plank, and not to attempt to frame it together with inserted divisions. Take a piece of plank (fir will do--a hard wood is preferable) 3 feet in length, I foot in width, and from 2 to 2 1/2 inches thick. Plane one side of this, and proceed to form the channels by making a series of transverse saw-cuts, I inch in depth, and by taking out with a chisel the wood intervening between every two such cuts. If afterwards two strips of mood, 3 feet long, are glued to the edges of the a-inch plank, it is clear that a box will be obtained divided just as required (see Fi,a. I4)· But the channels so made must by no means be of uniform size, and the planning out and true measurement of the chalinels and partitions requires great care, and is of great importance. Attention is therefore particularly requested to the following directions :-

The piece of plank is 3 feet in length. Rlark off first a clear inch at each end; a space of 34 inches then remains to be divided into 54 unequal channels. Let the first three channels at each end be each 5/8 of an inch in width, with divisions of 3/8 : thus 6 inches will be disposed of. Let the next three at each end be 1/2 inch channels with 1/4 inch divisions: thus 48 inches of space will be occupied, or 10 1/2 inches in all, and 12 pipes of the 54--viz,from CC to B--will be accommodated.

The organ-builder must now abandon the alternate arrangement of the channels, and proceed on the left or bass side only, by marking 6 more of the 1/2-inch channels with 1/4-inch divisions, and 6 channels of 1/4-inch width with similar divisions: 18 inches of the total space is thus taken up, and 2 octaves of pipes (viz., 24) supplied. There are now 16 inches of space remaining, which must-be made to contain 29 divisions and 30 channels. All the divisions must be 1/4-inch: this will consume 7 1/4 inches of space. Of the channels the first 6 may be 3/8 inch, and the remaining 24 1/4 inch each. This will account for 8 1/4 inches ; and the whole board has now been divided and meted out, with 1/2 an inch to spare--not too much allowance for unavoidable inaccuracy in marking and sawing. The amateur will do well to mark all these measurements with the greatest care on a ruler or " straight-edge" of wood, and then transfer them with a square and a pointed awl to the piece of plank, the edges of which you have previously dressed up perfectly true. No time should be considered as beinglost which is expended on bringing the measurements to the highest degree of accuracy. Then, with a sharp tenon saw, cut down on each line which you marked to the depth of a clear inch at least, as scored with your gauge on the edges of the plank. Take out the wood in the channels with a small sharp chisel and a mallet, and beware of cutting out divisions by mistake-a blunder which may easily occur. If it does occur, you must carefully insert a division, fitting it neatly in with glue; and you must mend any division which you accidentally injure. Do not attempt to pass the plane along the edges of the plank after the sawing, as the divisions would not bear it, but take off the rough saw-kerfs with any sharp cutting tool; then, with plenty of glue, put on two sides of inch stuff, three feet long each, and as wide as the plank is thick. Rub each backwards and forwards on the glued surfaces until they adhere perfectly in every part. At a subsequent period you must coat the interior of every channel, and the sides of every division, with an abundance of hot glue, using a brush of convenient shape, and allowing the glue to run into all corners and angles. This is of vital importance. When all is dry, dress the glued-on sides with a fine plane, so that the whole under side (on which the pallets are to go) may be perfectly level.

The pipe-holes (see Fig. 16) may now be bored. This will require nearly as much consideration as the planning of the channels It must first be clearly understood that the pipes of the two lower octaves, 24 in number, are not to stand directly upon, or over, their holes, but are to be placed according to the arrangement shown in the illustration of the completed organ (Fig. 20), and are to receive the wind through grooves or conductors leading from the holes to the pipe-feet. Now, these 24 pipes are, or ought to be, already made. It will be easy to lay them in a row, and to pile them one upon the other on a table or on the floor, so as to obtain a rough idea of the points at which the holes for them may be most conveniently bored. Thus the pipes CC, DD, and EE are shown as standing across the sound-board at the bass end; and CC, DD, and FF, across the treble end. It is evident that the holes for these may be so bored as to shorten the conducting grooves as much as possible. and the same may be said of the larger pipes standing contiguously to these. The amateur must consider the matter over well, with the pipes and board before him, and exercise his ingenuity in packing the whole cleverly in. It is by no means necessary that these 24 lower holes should be circular; on the contrary, while the actual hole on which the pipe stann's should be so, the hole which descends into the channel may be cut oblong, so as to supply the larger pipes with as much wind as possible; and the grooves between the two (which may wind in various curves as may be found convenient) may be as deep and wide as the organ-builder chooses. Make these grooves by cutting boldly down on the lines marked, to a depth of 3 an inch, with a strong pocket-knife, and by taking out the intervening wood with chisel. When the amateur approaches the hole upon which the pipe is to stand, and which may be 3/4 of an inch in depth, he should not cut the groove at once into it, but stop short 1/2 an inch from it, and mine under the little bridge thus left with his chisel, so as to conduct the wind into the pipehole without disturbing its circular form. Then cover over the groove (or several at a time) with stout paper glued on and rubbed down smooth. Each groove will then be an air-tight conductor. It is well to use a red-hot iron to scorch slightly the interior of such grooves as these, and to render all holes perfectly clear of splinters; and all pipe-holes may be " counter-sunk " to receive the pipe-foot by burning them with red-hot heaters, such as those which are used by the laundress.

It must be well understood that, as it is impossible to cut all the necessary grooves in the top of the soundboard itself, since some of them would interfere with those leading from the holes near them, it will be necessary to use an additional board expressly for the conducting grooves so excluded. This conducting-board is shown in Fig. 17. It is simply a piece of inch stuff, 3 feet long, and as many inches wide as may be requisite. Let us suppose that from all the holes in the line of A and B, Pig. 16, grooves have been cut in the sound-board itself, and have been papered over. Then the conducting-board being laid upon these finished grooves, and fastened down temporarily with a screw or two, cut the other holes (in the line of C and D) through it from beneath: and from these holes cut grooves in this new board, and paper them over as before. Of course, all the pipe-holes, on which the pipes actually stand, must be pierced in the new board; and a clever workman will not find it difficult to contrive the grooves on the under side (rather than the upper) of this board, so that when this under side is entirely covered with a sheet of leather glued on (the holes being cut out), and when it is fastened down on the sound-board with numerous screws, no paper may appear, but merely a neat surface of planed wood, with the counter-sunk holes for the pipe-feet. Any reader may comprehend the conducting-board with ease if he will take the trouble of makings copies, on separate bits of paper, of Figs. I6 and 17. Cutting out these copies with scissors, and placing 17 upon I6, so that ;he lines between Cand D shall coincide, the arrangement of the upper and under grooves will be obvious.

We shall now suppose that all the grooving has been well considered and cleverly executed, and that all the holes have been bored for the 30 upper pipes, as shown in Pig. 16. These 30 holes may decrease gradually in size from 3 an inch diameter at Middle C to 1/4 of an inch or less at the top;and they should be scorched through with red-hot irons, and (counter- sunk. We may now go on to the pallets.

Turning the sound-board with the channels uppermost, cover the whole of the channels with stout sheets of paper (old music-sheets answer well), glued on, and well rubbed down. When these are dry, cut with a sharp penknife a pallet-hole, 4 inches long, in the paper covering of each channel. As the channels are 12 inches long, it follows that 8 inches of each channel will remain roofed-in with paper, while 4 inches will be open. The row of
pallet-holes must be along that margin of the board which is to be in front when the organ is finished. Prepare the pallets from slips of any wood planed truly ; they be 4 1/2 inches in length, and will vary in width according to the size of the grooves which they are to cover. Their usual form may be seen in figs. 12 and I3. Let the amateur choose a strip of his smoothest and best white leather, 5 1/2 inches in width; to its dressed side glue the broader face of his pallets, a dozen or so at the time, and cut them apart with a sharp knife. Pin down a sheet of fine sand-paper on a bit of board, and strew on it a little common whiting. Rub the leathered face of each pallet on this whitened sand-paper until the roughened leather is full of the white dust. The pallets are then to be placed over the holes to which they are adapted, each being glued down upon the paper covering by the bit of leather, an inch long, which serves as a hinge, and between every two pallets insert a stout pin in the wood of the partition (see Figs. 12 and I3)· As each pallet is glued down, give it two or three smart taps with a light hammer that it may bed itself well on the pallet-hole, and see that every pallet
works freely, but truly, between its pins. A consideration of Figs. 12 and 13 will show how these pallets are kept shut by springs, and opened by pull-downs. In both figures B B is the wind-chest, a box of inch stuff, about 3 in. deep and 6 in. wide. It is usual to fix the back and the two ends of this with glue and screws to the sound-board, then to glue strips of leather to the edges of these, and to screw down the bottom board upon them without any glue, that it may be removed in case of repairs being necessary. The front will ultimately be closed in by a board furnished with strips of leather, and secured by screws put in with tallow. The chest, when thus completed, will be air-tight. The springs are made of brass wire, not annealed: in buying it ask for No. 17. Their form will be seen in Figs. I3 and Ig ; the amateur may easily make them himself by fixing in a piece of board a stout peg, X (Fig. I8), and two pins, Y and Z and by bringing the wire twice round X and once round Y and Z, as shown in the figure, afterwards perfecting each spring with pliers (Fig. 19).

The upper ends of these little springs fit into small holes in the pallets; their lower ends are fitted into similar holes in a slip of 3/4-inch wood, 34 inches long and Z inches wide; and they are kept in a position parallel to each other beneath their respective pallets by working in a rack or comb fixed to this slip, and made by cutting saw-cuts in a thin ruler of wood. The organ-builder will do well to fasten the slip of wood with the rack, to the end of the wind-chest, and to adjust all the springs, quite independently of the bottom-board. See that every pallet opens pleasantly with a gape of 1/2 an inch, or thereabouts, and that it shuts instantly, when released, with a smart snap. Into each pallet, near its front end, fix a little wire hook or staple, for the pull-down. Then screw on the bottom-board of the wind-chest.

It is now evident that some contrivance must be resorted to in order to obtain an air-tight connection between the pallets and the levers outside the chest. Mark carefully on the fore-edge of the bottom-board of tile chest the central point beneath each pallet-hook. Take a strip of sheet brass, 3 feet in length, about 1/16 of an inch in thickness, and 2 inches wide: it may be obtained cheaply at the ironmonger's. Drill holes for screws, a few inches apart, along its edges. Secure it temporarily beneath the bottom-board, so that the row of pallet-hooks may be exactly over its middle line. Then, immediately under every pallet-hook, drill a hole through the brass of such a size that a piece of the brass spring-wire may glide pleasantly through it. Remove the brass plate, and bore the holes marked by the drill on the bottom-board through with a bradawl, burning them clear with a red-hot wire; then glue a strip of leather, 2 inches wide, over the row of holes, and on the leather screw down firmly, with many screws, the brass plate. Prepare 54 pull-downs of the brass wire; these are about 3 inches long, having a screw-thread tapped for an inch or so at one end. Thrust the untapped end through the hole in the brass plate belonging to it and through the leather above, and form this end with pliers into a hook. Connect this hook with the pallet-hook by a little S hook made of any wire, and see that all works smoothly (See Figs. 8 and g). Before drilling the holes, take the precaution of trying the drill on a spare bit of brass, and, if necessary, alter it a little by means of a whetstone.

IV Putting the Parts together--Key-board--Csbel Betion--Treble Pipes--Conclusion.

We now begin to draw towards a conclusion of our labours. We have made the bass pipes, the bellows, the wind-chest: we have now to put the whole together, and add the connecting mechanism. iittming to the view of the completed organ (Fig. to),

If the stopped wood pipes, and LL are the open Metal pipes. n B and A B are two stout boards of any wood, forming the sides and main supports of the instrument They should be of inch and a-half stuff, and their lower edges should be let into cuts, c, c. The hack-edge of each of these boards being straight, the fore-edge may be neatly cut in stages, so as to diminish the width of the board from I8 inches, or even 2 feet, at the cills to Iq inches at the top. These side-boards must be connected together by cross-rails D u, of inch stuff, mortised firmly into the boards, and fixing them 3 feet apart. If the organ is not to have a regular "case" over all, the ends of these rails will not look amiss if brought boldly tltuo?cRlz the boards, a large peg bein g passed through them afterwards. The upper edge of the lower rail may be 8 inches from the ground, and the upper edge of the upper rail z feet 3 inches. Similar rails, level with these, will be fixed at the back. Screw two strong wooden ledges to the inside of these boards, and on these ledges rest the ends of the middle-board of the bellows, at the height of I foot from the ground. Ledges must also be screwed strongly on, for the sound-board, etc, to rest on. Secure the bellows to the ledges by three sc rews at each end.

On the upper rails the key-board E is to rest. This you will, of course, not attempt to make. You may be able to pick up an old one for a trifle. Pianofortes are now so common, that their cast-off keys are common too, and two shillings or half-a-crown will often buy a sufficiently good set from some cabinet-maker, or at a music-shop. Whatever its extent, you must neatly alter it to the compass of 54 notes-- c c to B in alt.; but be careful that you only cast aside the keys at each end which may be supe rfluous, as you will find they are all stamped with the name of the note which they are intended to act upon. Take the opportunity of cleaning the keys nicely, and of renewing the baize or other muters which secure their silent action.

Leaving the keys for the present, we may proceed to place the wind-chest and sound-board F on ledges screwed to the side-boards, at a height of 6 or 8 inches above the keys; and at a further height of 4 or 5 inches above the top of the sound-board fix a board of S-inch pine, M. In this, called the rack-board, holes will be bored to receive the pipe-feet, and to support all the pipes firmly in a vertical position. Above the level of the rack-board you need not carry your sideboards, unless you intend to form the whole into a regular "case." notches. A little blacklead should be rubbed on each backfall, to ease friction. If you manage this cleverly, each pull-down will come through a hole bored in the foreend of its own back-fall when the bridge is screwed to the under side of the chest ; and on the tapped end of the pull-down you will screw a small nut, made by punching bits out of old leather (new will not do), such as every saddler will readily give you. On replacing the sound-board in the oi·gan, the tails of the backfalls ought to be over the tails of the keys; and the stickers, little round rods of wood, should be neat and perfectly vertical. Put a little morsel of baize or other cloth on the ends of each sticker before inserting it, that wood may not rattle against.wood.

The sis right-hand back-falls will be worked by means of a " roller-board." A roller is a slip of ~-inch wood, I inch wide, and of the necessary length to transfer the action of the keys from one side of the organ to the other. It should be a little r ounded off at its edges; and each end has a wire, on which the roller revolves between studs or blocks fixed on a board behind the row of stickers. If now an arm of wood is fixed into the roller above the key-tail of ccs, and a similar arm be fixed into t he roller below the tail of the back-fall belonging to the right-hand pallet, it is clear that by using two short stickers--one from the key-tail to its arm, and the other from the second arm to the back-fall--the key will act on the pallet exactly as if a single sticker connected the key and back-fall. We shall have six of such rollers, neatly arranged on a thin board, 3 feet long and 5 inches wide, and every pallet will thus be under command. Much of the comfort of the player will depend on the smooth a nd si~e~2t action of your back-falls, etc.; spare no pains, therefore, with all this mechanism. The little leather nuts, or buttons, will, of course, enable you to adjust the keys to a perfect level.

My readers cannot have failed to notice that I have hitherto said little or nothing of the 30 treble pipes. I have, in truth, postponed any mention of them until the last, because I venture to hope that, if you have constructed the organ thus far well and soundly, you may think it worth your while to purchase 30 metal ones. These metal pipes, if they are pipes for your treble. of the kind called "Open Diapason," will cost about thirty shillings; they should be of decidedly small scale and soft tone, ap proaching to that of the stop called "Dulciana." Any good organ-builder will supply them, or they may be had from a regular pipemaker If I mention Mr. T. R. Willis, Minories, London, it is because I have found his pipes invariably good, and his charges mo derate. All requisites for organ-building can also be purchased at his establishment The metal pipes will, of course, be planted in holes in the rack-board like the wooden ones. If a few of the larger, ones will not stand conveniently, use a small conduct ing-board for them. The purchase of metal pipes, however, may not be practicable. In this case, by all means make the treble as a "Clarabella." Put the pipes together just as you did the larger ones; of course, as they are to be open, they will be double the length of stopped ones of the same pitch. Middle C will be two feet from the mouth to the top, and should be made much smaller in scale than the stopped pipe of the same length. The Clarabella is generally made with a reversed mouth; that is to say, the chamfer, or bevel, above the lip, is inside the pipe, the outside presenting an unbroken front from top to bottom, with the narrow mouth cut in it; The throat occurs below the mouth, as in other pipes, and the cap is glued below the mouth on the fron tboard of the pipe. The quality of tone produced by this device is fluty and pleasing. Such pipes are tuned by means of a little lid of pipe-metal or tin, or thin brass, fixed in a saw-cut in the top of the back-board of the pipe; the pipe being cut as n early as possible to the exact pitch of its note, then the bending down of the lid slightly flattens, and the raising of it slightly sharpens, the tone, as may be desired. The stopped pipes are tuned by driving in the stoppers with light taps of a hammer for sharpening, and drawing them upwards for flattening. By all means handle metal pipes very tenderly. They are tuned by
cones, shaped like the " extinguisher" of a candlestick. The pipe being first cut with scissors nearly to the pitch required you shar pen it by widening the top a little with the cone, and flatten it by pressing the hollow of the cone on the top, so as to contract it slightly.

If a pianoforte or harmonium in good tune be at hand you will do well to tune your organ by it, note by note, exerting all your skill to regulate your pipes; but also to make them of one uniform tone, not one louder than another. This is a delicate bu siness, and you should attend carefully to the following directions :
1) If a pipe gives a coarse, rough note, or if it makes a chirp-or whistle before its true sound is heard, diminish its supply of wind. This may be- done by planing or otherwise re pipes for your treble. These metal pipes, if they are of the kind cal led I' Open Diapason," will cost about

The purchase of metal pipes, however, may not be practicable. In this case, by all means make the treble as a "Clarabella." Put the pipes together just as you did the larger ones; of course, as they are to be open, they will be double the length of stopped ones of the same pitch. Middle C will be two feet from the mouth to the top, and should be made much smaller in scale than the stopped pipe of the same length. The Clarabella is generally made with a reversed mouth; that is to say, the chamfer, or be vel, above the lip, is inside the pipe, the outside presenting an unbroken front from top to bottom, with the narrow mouth cut in it; The throat occurs below the mouths as in other pipes, and the cap is glued below the mouth on the front board of the pipe . The quality of tone produced by this device is duty and pleasing. Such pipes are tuned by means of a little lid of pipe-metal or tin, or thin brass, fixed in a saw-cut in the top of the back-board of the pipe; the pipe being cut as nearly as possible to the exact pitch of its note, then the bending down of the lid slightly flattens, and the raising it slightly Sharpens, the tone, as may be desired. The stopped pipes are tuned by driving in the stoppers with light taps of a hammer for sharpening, and dra wing them upwards for flattening. By all means handle metal pipes very tenderly. They are tuned by cones, shaped like the "extinguisher" of a candlestick. The pipe being first cut with scissors nearly to the pitch required, you sharpen it by widening the top a little with the cone, and flatten it by pressing the hollow of the cone on the top, so as to contract it slightly. If a pianoforte or harmonium in good tune be at hand, you will do well to tune your organ by it, note by note iota, wresting all your skill to regulate your pipes; that is to make them of one uniform tone, not one louder than another. This is a delicate business, and you should attend carefully to the
following directions :
I. If a pipe gives a coarse, rough note, or if it twitters a chirp-or whistle before its true sound is heard, diminish its supply of wind. This may be done by planing or otherwise reducing the inner side of the cap, so that the windway " may be narrower ; or it may be done by partially stopping the hole in the pipe-foot with a wooden plug or plugs.

3· If a pipe "over-blows'" that is, sounds a note an octave above its true pitch--it has too much wind, or the whole wind of the organ is too forcible. In this last case, take some of the weights off your bellows.

4· If a pipe ciphers, that is, sounds when the key is not pressed down--a rather common occurrence, and very annoying--look at the pallet and see whether anything prevents it closing tightly, or whether the spring has slipped, or is too weak. The great desideratum is a sweet and soft tone : hollow and humming in the bass, clear and duty in the treble. No attempt must be made to obtain power from so small an instrument. If your work is sound and good, your stoppers fitting well, and your regulation well managed, your little organ ought to be a pleasing accompaniment to the voice.

I am unwilling to take leave of my readers without a few more remarks for the information of those who may desire to pursue the subject of organ-building somewhat further. The organ which we have described is, of course, of the tiniest kind: I would sh ow, in few words, how its dimensions may be expanded by workmen whose skill and-whose means are equal to the undertaking.

Suppose that, instead of one set of 54 pipes we desire to have two sets, or Io8 pipes, and that we wish to use either set, or both combined, at our pleasure. In this case, after making a sound-board with 54 channels, as before, and planing its top ver y truly, we prepare a board of inch stuff (mahogany, oak, or cedar) of the same size as~ the sound-board, and also very truly planed. This board will be screwed down upon the sound-board, bi~t between the two a couple of sliders willbe placed. These slide rs are rulers of smooth wood, a few inches longer than the sound-board, 3 or four inches wide, and quarter of an inch, or less, in thickness. They are made to slide from right to left, and vice versa, between fixed pieces of the same thickness, called "ta bles." Thus the whole sound-board will consist of three layers of wood--the sound-board itself, th8 sliders with their tables, and the upper-board. And now it is plain that, if you bore your pipe-holes through all the three layers, you may close all the holes at pleasure by shifting the slider, so that the holes in the layers no longer coincide. Of course you will arrange a "sLot," Or mortise, in each slider, with a strong pin driven into the sound-board to adjust the distance traversed by the slider. Rub sliders and boards with plenty of blacklead, and, in screwing down the upper-board to the tables, glue ships of paper to the latter, in order to allow a little play to the sliders, which should move easily to and fro. To do all this well requires good wo rkmanship and good planes.

The pipe-holes must now, of course, all be within the limits imposed by the dimensions of the sliders; hence the conducting may become complicated. This leads me to describe a method of avoiding conductors altogether. Let us suppose a sound-board, 3 fe et long but only 6 inches wide, with 42 channels. This will easily accommodate the pipes above Tenor C without crowding, and you may have two sliders on it. Let us suppose another sound-board, 3 feet long and 6 inches wide, with It channels only, at interv als corresponding with the feet of the larger pipes, for which alone it is intended. On this also you may have two sliders. If now the sound-boards be glued edge to edge, one wind-chest may serve for both ; the It bass pallets being pulled down at the back, the 42 upper pallets at the front, and, by a little management of roller-boards, a very symmetrical arrangement of pipes may be attained without a single conductor. I have known a very compact organ to be made in this way, having two bass "stops" (viz., sets of pipes) and 4 treble stops. The stops were as follows :-


BASS.
Stopt Diapason (woods)
principal (metal).
TREBLE.
Stopt Diapason (wood).
Dulciana (metal).
Principal (metal).
Flute(wood).

The organ complete will be 8 feet 2 inches high. If this is too high for the room it can be made lower by planting some of the largest pipes at the back of the organ on the sound-board, and conveying the wind to them from their proper channels with B i nch tubes.

For the benefit of those who may not yet have got so far as the grooving for the pipes, I may mention that, if the four largest pipes are placed two at each end, and about eleven of the next largest are arranged in a line along the front, it will have a very pretty effect, and a case for the upper part be rendered unnecessary. The pipes may then be stained and varnished, or painted and ornamented according to taste. If it is required to get at any of the pipes at the back it will only be necessary to lift out one or two pipes where required.
--------
Before bringing this paper to a close I must i point out an error in the drawing of the bellows, Fig. 6. Both folds are represented as inside folds, whereas the upper one should be an outside fold. If you look at the diagram of the complete organ you w ill see what I mean. This is an important point, as it is the only way to secure an equal pressure of wind, and constant equality in the pitch of the instrument, no matter what amount of wind there may be in the bellows. Even if the bellows has been compl eted, it is worth while making the upper folds afresh. The leather will come of easily if damped, and can be used again.

Having set this matter right, I have only to suggest a method of finishing-the instrument, which I will do in my next.

 

A case, however, is a great protection to an organ in a room, as it keeps out the dust and dirt. If covered in the front with a piece of silk or damask, like the old high pianos, it will look very nice, and will not shut in the sound too much. It shoul d be made so as to be easily opened for access to the pipes. The wind-trunk H is shown in the cut as rising from the end of the bellows, and entering the bottom of the wind-chest. But it may be placed more conveniently at the back of the organ; and, in an y case, its dimensions may be about f inches by z inches. You will make it of I-inch board, putting it together like a pipe, and gluing it very well inside; cut an oblong hole 6f inches by I4 inch, in the trunk-band, and in that part of the wind-chest whi ch is most convenient (its back, for instance), and make a tidy fit of the trunk into these apertures, using leather and glue to secure all joints and all mitred angles. Take care that dust or chips do not remain in the interior of the bellows and chest. After all is dry, you may cut through the trunk, about its middle, with a backed saw, so as to enable you to separate the parts; and one of your last acts (in finishing the organ) will be to glue a slip of paper or leather round this saw-cut. The bellows will be conveniently blown by means of a pedal made of any hard wood, having a little wheel let into the end which raises the feeder, and having one or two small spikes in the flattened part on which the foot is placed. ?'he block on which this pedal wor ks will be best screwed to the floor, independently of the organ frame, and you should shape the pedal so that the feeder may have its full play at each stroke. Load the upper-board of the bellows with two common half-bricks (quite dry), wrapped in paper or baize; on inflating the bellows, if your work is good, no hissings should be heard, and the reservoir should descend with extreme slowness. The places for the rack-board holes may be determined by laying a sheet of paper on the sound-board, and rubbin g it with your hand until it takes impressions of the pipe-holes; the centres of these impressions can then be pricked out with an awl on the rack-board, and the holes bored with centre-bits. You will now perceive the advantage of having left the pipe-fee t unglued in; glue in each of them now as you plant the pipes, and by a little adjustment of the pipe-foot, see that every pipe stands vertically. The mouth of every pipe must, of course, be clear of the side or back of its neighbour. We must now make th e action. It may be hoped that you already comprehend it pretty well by an inspection of Fig Iq. In the tail of every key, ~ of an inch from the end, bore a small hole, and burn it larger beneath than above. This is to receive the wire of the sticker 4 Fi g. Iq, and to allow it to work freely. There will be 54 back-falls, made of any wood, t- of an inch thick, and I inch in width. Observe that the tail of every back-fall(except the six most to the right, or treble end, of which more presently) must be exac tly over the key-tail to which it corresponds; and that its fore-end must be exactly under the pull-down of the pallet to which the key corresponds. From this it results that the back-falls will not be all of the same length, and that they will not necess arily be parallel to each other, like the keys. You will do well to mark the places of the key-tails on a ruler of wood; then, turning the sound-board over, fix this ruler temporarily in such a position as to enable you to mark the line of action of each back-fall on the bottom board of the chest. Then cut 54 notches or grooves, an inch deep, with a saw and chisel, in the broader face of a small back of hard wood, z inches by I~ and 3 feet long, to form a "bridge." Each notch must have the slope or inclin ation proper to its back-fall; and the 54 back- fails will work freely in the 54 notches on a single wire running the entire length of the bridge through every back-fall, and fastened down at intervals with small staples driven into the wood between the

 


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