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board exposed. The next step in order is to place on the top part or cope frame of flask—this part carries the flask pins which fit into holes made in drag. The cope is then rammed full of sand, at the same time a round stick is rammed up in this part to form, when removed, a hole through cope to allow the molten metal to enter mold. After the cope is rammed up it is lifted from drag, laid to one side until pattern can be removed from drag, and runners made from mold to point where gate or hole comes through from top. After this procedure the cope is replaced on top of drag, the two clamped together, and the mold is then ready for the metal to be poured in.

There are a few other necessary adjuncts well known to the molder in the foregoing procedure, but they will serve no purpose in this article and are therefore left out.

The reader, to understand how to make even plain patterns, should familiarize himself with the order in which molders proceed with their work.

The Use of the Core

As the use of cores is very little understood by the ordinary mechanic, I will explain their use in this connection, as this is one of the prime factors in patternmaking. The word core, when applied to foundry work, has a different meaning than when applied to other branches of mechanical art. That is, an understanding of the meaning of the term as applied to one does not convey an understanding of the same term as applied to another. We are all familiar with the word core when applied to the different fruits that have them, but when it comes to the mechanical arts we have to be informed as to its meaning. While the word core primarily means the center or central part of anything, in molding this is not the case, for often times there are more cores on the outside than in the center of a casing. But the term core as applied to foundry practice means a baked body of specially prepared sand, formed the desired shape by some means (most generally in a box whose internal shape conforms to external shape of core). This sand packed in said box while damp, is removed on drying plate and placed in oven for the baking process. Speaking of cores reminds me of a joke I played on an old fellow who was the floor sweeper in our shop a number of years ago. I happened to have a round core on my bench for some purpose at one time when he was near. I called him over to look at it. I picked it up and showing it to him, said: "Did you ever see any dynamite?" With wondering eyes, a grave look on his face, and a hushed voice, he said: "Is that dynamite?" He seemed very anxious to get away until I told him what it was.

Why the Sand is Coarser

The core sand is a much coarser sand than the molding sand, and has to be so on account of the gases that form when the molten metal surrounds the core. Being course, it forms, when packed in a core box, small minute air cells and passages which convey the gases to large vent holes made by the core-maker with a wire, said vent holes conveying the gases to outer edge of core where provisions are made to further convey it off through the mold between the upper and lower part of flask or some other more convenient place to atmosphere. Ordinary river sand is used in many foundries, but a coarser grade gives better results. Core sand when being prepared for core making is first sifted through a riddle to get out the gravel and other foreign substances. It is then mixed with some kind of an ingredient that will give it more adhesive power, causing the grains of sand to adhere to one another better. There are different things that might serve for this purpose. Until of late years common wheat flour was used to a great extent, but now various kinds of core compounds are extensively used. After the sand

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has been prepared, it is placed in core box, packed in tight, vented properly, shook out on drying plate, and baked in oven as before stated. After the baking it can readily be handled without breaking. Deeming the foregoing relative to the making of cores to be sufficient, will take up their use.

How Cores Are Used

Cores are used to form holes, cavities and recesses in castings to conform to various designs, and to serve various purposes. The most closely associated thing to core is its core print. Every core has its core print, which is necessary to locate, sustain and hold the cores in their proper place. When one contemplates making a pattern they should look the casting over carefully and see how the pattern can best be placed, which side up and which down, so that the cope or top part can be lifted off without tearing mold, and also see if the pattern can be drawn from lower part of drag without tearing up the sand in it. There are a great many instances where the casting can very easily be fixed so that it will serve as a pattern, even though it be broken in several pieces. It is a very easy matter for the molder to lay these pieces together in the mold and produce a whole casting.

The use of a casting to serve as a pattern can be determined by noting the shape and seeing if there are any projecting parts that preclude the possibility of the casting being drawn from the sand in any way without tearing it up. If there are projecting parts they might be easily removed by hammer and cold chisel or other means, and a loose wooden piece the right shape substituted and located in the right place by loose dowel pins. This allows the molder to ram them up in their proper place on pattern and remove the pins so that the main part of pattern will be free to move away from these loose parts, leaving them in the mold to be drawn in at proper angle after main parts of pattern has been lifted out. Or these projections could be covered entirely with a core print which should extend to top of pattern. A core box should then be made the size of this print and the projecting part made of wood placed inside in its proper place. All holes that have been drilled or tapped in casting that is to be used for pattern should be plugged with wood. Other holes, if having considerable taper in the right direction, can be left as they are. The casting should be filed up nicely to insure it slipping out of the sand.

Work for Flat Surfaces

In making a pattern or preparing a casting for use as a pattern, work with the idea in view of the greatest amount of flat surface being up in the mold unless there are other features in the shape that prevent it. There is no fixed rule relative to this, for it often happens that it is much easier to have least amount of flat surface up. The shape alone determines this. Imagine yourself bedding the pattern in the sand with top side exposed. Study the situation closely and see if there is anything that projects that would pull the sand up with it. Would like to correct some impressions that exist in the minds of some mechanics who know what pattern-making is, but know little of the character of the work. I have often had men ask me if I didn't have to be very particular to get the exact shape and size of the casting in the pattern. To this I would answer, in a certain sense, yes, and in a certain sense, no. We have to be particular about some things and others not so particular. There are very few instances where exact shape is required, and when the exact size is demanded, allowance is generally made for the casting to be finished in machine shop to exact size.

In pattern making, as in every other trade, the work

has its limits of variation. Would venture the assertion that the fine watch and instrument_maker has his limits of variation. When it comes to exactness, it is something that is very hard to get. If the reader doubts this statement, would like for him to try and produce a perfect cube out of wood about 11⁄2 inches in size. This means that the sides must be perfectly square with the sides adjacent thereto, and that it must measure exactly the same between the six opposite sides, and the same across the corners. Don't depend upon your rule for these measurements, but get a pair of outside calipers and try across the sides. In squaring up, you obviously must have a perfect square, which is not often found. Hold up to the light and see if you can see any light under the blade. I am here reminded of a wager that I accepted from a friend some years back. He said he would buy me a hat if I would make a block that was perfectly square. He said it was impossible, as though there was something in nature that prevented it. I promptly refuted this and said I was satisfied I could make the block. After working on the job at odd times for some weeks, I finally succeeded in getting a block with all sides perfectly square with each other, but got tired of trying to get the block a perfect cube and gave it up. Pattern Makers Successes

The secret of the success of a great many patternmakers lies in their ability to discern between the particular and non-particular phases of their work. A great many pattern-makers waste a great deal of time fitting templets to different sides of castings they are making pattern for, when the exigencies of the case do not require it at all. A pattern that will very likely be among the first to be needed in a planing mill is one for a pulley bushing; these being subjected to constant wear, I will have to be renewed in course of time. There are two ways of making a pattern for a bushing, the preferable way depending upon the size and length thereof. One is to split or make the pattern in halves along its central axis, having prints at each end to support central core, and cast it on its side. The other, making pattern solid with print at only one end and casting on end. These patterns can be turned up by the wood-turner.

Prepare pieces for turning patterns in halves by getting them out about 1/4 inch wider than size you wish to turn them, and half this width for thickness, and about 2 inches longer than length of pattern and prints (would here pause to say that length of prints for split pattern should be somewhere near their size in diameter, but pattern which is cast on end about half of their diameter will suffice for their length). Fasten these pieces together at their ends by some secure method. About the best means at your command will be by putting a screw at each end. Even up the ends of the two pieces thus screwed together and place in lathe with lathe centers coming in the point. This will give you, when the pattern is turned, two perfect semi-circular pieces. After turning they should have holes bored and dowels placed at each end to keep the halves properly matched together. These dowels should be about the length of their diameter, having a rounded point, and should be loose enough to allow the two to be taken apart freely. Don't do as most of the inexperienced generally do-turn the pattern up out of a solid piece and take it to a band saw and split open. This takes out the thickness of saw cut and therefore makes it out of round, in addition to the most likely thing of getting off the central axis with the cut. A pattern thus made puts one-half in upper and one in lower part of flask. the parting line running through the center. This facilitates molding, and is the reason why it is so made. Let the reader understand that any num

ber of loose parts of the pattern can be either impressed in the lower or upper part of mold. Do not get the impression, however, that because they are loose in the pattern they will be loose in the casting. It will be like the Irishman's wasp, "You will find him all right in the end." All parts united. I get amused at men sometimes when they see a pattern for a certain casting that they have ordered a pattern for. As the old fellow says, "They get wool gathered." They want to know why this and why that, until you have to teach a few lessons in pattern making.

I would suggest that before you make a pattern for a bushing you consult the foundryman from whom you expect to get your casting. It might be possible he has what you want in his stock of patterns. Bushing patterns are very common in the foundry and all of them have a stock of various sizes on hand.

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ing being so much thicker at this point than the width of this hole, necessitated the use of a core to form it. At P, on C, Figure 5, is shown the core print for this hole. D is core box for the core. Note that this box is in halves and is shown apart slightly, showing the way it is split. E is the core, made in box D. You will notice that the ends of this box are open; this allows the core-maker to place one end on bench and ram the core sand in from the other. When it is ram

Figure 4

Fig 4

med full he smooths it off with his trowel, makes a sufficient number of vent holes, and it is then ready to lay on plate for baking process.

A and B, Figure 5, are two halves of core box for core L, which is for bushing pattern J K. This pattern, as you will note, is made in halves and has prints, P, at each end to support core. This pattern lying on its side in the mold necessitates having prints at each end, but with bushing pattern H, which is cast on end, only one print is necessary, as core I stands on its end in the mold. PS in the pictures indicates core prints.

Figure 6 is an angle valve body. E, with its attendants, pattern F, core G, half-core boxes C and D and mold and flask A and B. A is drag part of flask B, cope part. Note the gate hole in B, and the runner, leading to mold directly opposite in A. When the two come together the hole is directly above the runner. This allows the molten metal to drop through hole into runner

the defects before I point them out. To begin with, surfaces A will be the sides that come up when mold is complete, consequently the sides that go down next to follow board for the ramming up of drag or bottom half. This will not, of course, bring the parting between the upper and the lower part of mold on a straight line with joint of flask, but that makes no difference as the molder can make parting line drop below or raise above this flask joint inside of mold, to suit shape of patterns. This rise and fall, however, must be gradual (on the order of the

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and then flow out into the mold. Pattern F is in halves as is also the core box, and the impression is shown in the halves of mold. Notice the impressions left by the three prints on pattern F. This, as you will see, gives the core G three resting places. The core is made in halves so that one half can be made and dried and then the other made and pasted to it, and also dried. The loose pieces at H, in C and D, are made loose because they have a cut under surface to form a raised seat for valve. They come out of box with core, and can then be drawn back and removed from around it.

Figures 7 and 8 are edge outlines of journal box patterns that we received at one time to make some castings from. They represent the efforts of a carpenter who knew very little about pattern-making. However, they have the general defects always present when made by someone not familiar with pattern-making, and serve as good example from which to note corrections. Would have the reader look these over and see if he can detect

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cause trouble? Look at points D, Figure 7, where the same conditions exist. Points D, Figure 8, are not so bad. These shoulders would be much better if made like the dotted lines show, having a little bevel. In Figure 7 that part of the mold between line G and H is a part of the cope or upper half. This is what we term coping down and lifting out. The holes at E and F for a half inch bolt should be nine-sixteenth inch at F and fiveeighths inch at E. If straight holes are wanted, they should be drilled after casting is made. If any holes are desired at any point where the hole is smaller than the thickness of metal through which it passes (as at G, Figure 8), they should be drilled.

Questions relative to the foregoing cheerfully invited. Same will be answered through the columns of THE FURNITURE MANUFACTURER AND ARTISAN.

The Orinoco Furniture Co., Columbus, Ind., has electrified its plant, retiring the steam equipment, in use since 1890.

VENEERING DEPARTMENT DETAILS

Buy the Best Stock Possible; See That You Get What You Buy---Selection of a Glue Tank---Cooking and Care of Glue---Woods Must be Understood By ALEXANDER T. DEINZER

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HE COMMON weakness of many furniture manufacturers, whether buying lumber, glue, varnish, veneer, or anything else, is to make a drive at saving money in the first cost, to try to buy it cheaper, to pick up bargains. Hundreds of buyers have been badly stung. I hope this statement is not misunderstood. If you can buy gold dollars for fifty cents you will do so, but be sure you are receiving gold dollars. If you thoroughly understand veneers and can safely pick up bargains, it will be to your interest to do so.

and you can tell within just a few minutes how many feet of each lot you have on hand. Simple? Of course it is. Besides the nicety of this system, it lends a great deal to general carefulness throughout the handling of the veneer. Try it and see what you

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ALEXANDER T. DEINZER

The first thing of importance, and the thing that should dominate in shaping the purchase of veneer, is to get the best stock possible for the purpose in hand. Ruptured veneer is, in my opinion, expensive at any price. I have been told that some of the manufacturers receiving veneers with the fiber broken will run it through rollers to press the fibers together again. Veneer is thin, at best, and if subjected to sufficient pressure to force the broken fiber together again, the unbroken parts will be crushed and bruised in the process. You can buy ruptured veneer very cheap indeed, and there are furniture manufacturers in business today who are buying this grade of veneer and believe they are getting a bargain.

Space does not permit writing any more about the question of buying but enough information has been given to show how really important is the knowledge to select veneers.

Making Copies of the Veneer Order

A good idea in purchasing veneers is to make triplicate copies of the order. The original being handed to the salesman or mailed to the veneer company, a copy to the veneer inspector or the man having charge of the veneers and a copy retained in the purchasing department. In all cases keep the samples of the flitches you buy and compare them with the stock when it arrives. Have all the veneer inspected and measured as soon as received. A good idea is to give a lot number to each log and report this number to the cost department and to have all piles of veneers numbered, keeping an account of every pile as you would the lumber in your lumber yard. Whenever the veneer cutter takes veneer from the pile, he must report the quantity to the inspector, or, if the factory is large enough, the veneer should be delivered only when a requisition is presented. This requisition should bear the job number for which it is intended and is, of course, returned to the cost department. There are several advantages in using a system of this kind:

think of it.

There are many veneer buyers who will buy very narrow stock, saving a few dollars per thousand when they really require principally wide stock, or possibly both. You must remember that the great advantage in buying wide stock is in the beautiful figure effect. Again, it costs money to joint, match and tape

veneer.

In our modest business we veneer many couch sides. These sides are usually 71 inches long by 534 inches, 612 or 912 inches wide. We buy veneers 12 feet long, 6, 7 and 10 inches wide, and have practically no waste. We all know that labor costs bring up the price of the furniture. Figure your labor, plus burden, plus waste, and you will find that the cost of matching and jointing narrow veneer is far greater than the small additional cost you would likely be compelled to pay for wider stock.

Study the conditions of your veneer room. You should be able to determine what you require and buy accordingly. There is one best way to do everything. If the manager, superintendent and foremen know "how" you can manufacture furniture at lower prices, increase sales, raise capital and earn profits.

The Ways of Winners

One hears so many furniture manufacturers say: "There is no more money in the furniture manufacturing business." If you should cite the cases of some of the successful manufacturers they will say: "Those people made their money years ago when labor and lumber were considerably cheaper than they are today." There are furniture manufacturers who are making money today but there are many who are losing money. The successful furniture manufacturer knows how to manufacture furniture at a profit and is doing so. Supposing our successful men, as, for instance, Messrs. S. Karpen, Macey, F. Stuart Foote, Henry Schuerman, Strudley, and Mallen, were turned adrift among strangers, without a dollar. Within just a few years' time these men would again erect factories and be the important factors in the furniture manufacturing trade they are today. And why? Because they thoroughly understand furniture manufacturing. They are alive. Forget that there is no money in the furniture manufacturing business. If you

First-You know the exact amount of veneer required employ men who do not show results, engage men who for the job.

Second-You eliminate waste, for your men know very well that they must account for every foot.

Third-You know when your veneer is running low and have sufficient time to order, not depending on Smith or Jones to report and possibly hold up the veneer room on account of delay in not getting the stock. Fourth-You have a perpetual inventory of all veneers

can. If your equipment is not strictly modern, it behooves you to investigate some of the modern machines and see how greatly they increase production at a lower cost. Engage the very best men you can (regardless of salary) to take charge of your veneer, gluing, cabinet and finishing departments.

Until recently the glue tanks used in veneering, gluing and cabinet departments were the crudest, the meanest

and the most neglected in the long list of equipment required in a woodworking establishment. For years glue was heated in open pots, and we all know that evaporation weakens glue; makes it too thick for use, and also makes it very uneven in quality. An improvement in the right direction was to put a cover over the tank or glue cooker and to provide the cooker with a stirring rig. I have been asked at various times: "Is it well to stir glue while being dissolved?" There is no objection whatever to this method and, in fact, in many cases where the goods are used very heavy and in large quantity, agitation by paddles is often necessary to secure prompt and efficient results. The only objection I know of is that it raises scum and foam that otherwise would not be apparent, but this can always be overcome by the consumer using glue that works free from foam, whether agitated or not. In many furniture factories one will find the old style iron kettle. Iron equipment is expensive for the reason that it will not stand up with copper, brass or aluminum. Iron rusts, and the rust impairs the color and quality of the glue liquid, and copper, aluminum or brass are practically self-cleaning.

The Glue Tank

When buying a glue tank select one having a greater height than diameter. A high tank with a small diameter is decidedly preferable to a wide and shallow tank. You will appreciate that the stirring rig can work better in a tank where the height exceeds the diameter than in a tank being low and wide. It should have an air-tight glue chamber (to prevent evaporation) and surrounded by a water jacket, the water in the jacket being heated either by direct injection of steam or by use of copper heating coils. Some of the progressive factories are using electricity to heat their glues. Be sure you have a thermometer on the cooker and have this attached in some conspicuous part of the cooker so that the man preparing and cooking the glue can watch the temperature. Do not at any time permit the temperature to exceed 150. This is a great fault in most of the furniture factories. Time and again I have observed the temperature from 165 to 200. From force of habit I observe the temperature whenever I pass a glue cooker. It is very seldom that I find the temperature at 150, or below that point. One hundred and seventy degrees seems to be the favorable point with most glue men, Some of these fellows will tell you "It is not necessary to gauge glue heat; the glue will hold anyhow if it is a good glue. We don't care about your figures or methods, we get results 'anyhow,' don't we Fritz?" Ask them do the joints ever come apart: "Yes, but that isn't our fault; them there fellers in the office buy the glue and we aint to blame if it's no good." It is not uncommon to find plants in which glue is prepared by subjecting it to the direct application of steam. So many workmen labor under the impression that it is necessary to heat the glue at a very high temperature in order to dissolve it. This is a mistaken idea. If the glue has been properly softened, it will dissolve at a low temperature.

Testing the Glue

A thermostatic valve which operates automatically will keep the temperature in the glue chamber between 145 F. and 150 F. This apparatus not only prevents overheating, but eliminates the time and care of keeping the temperature where it should be. Again, this apparatus not only facilitates economical melting of glue, by preventing evaporation, waste, formation of scum, sour and dirty glue, but it also insures uniform "spread."

A few years ago I entered a furniture factory early on a Monday morning (I must not forget to say that this was during mid-summer). When I opened the door I was nearly overcome by an offensive odor which I recog

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nized as coming from the glue room. The workmen did not care to work in that department. In fact, the workmen throughout the entire plant were very angry. found the man in charge of the glue room and suggested that he must have old glue in the cooker, some that had possibly been left there for a day or more. He said: "Yes, but the glue is no good or it would not deteriorate." I have found glues that will stand a lot of abuse. Nevertheless, every glue will decompose when left over night, especially over two hot nights and one day, as was the case above cited. Glue should be free from heat during the night and should not be mixed with fresh glue the next morning for full value will never be secured from the glue used that way.

Some manufacturers and glue users may say: “Glue is far superior in quality today to what it was fifteen or twenty years ago." This is true, hence your product should have been improved.

The Old Way

There are a few small cabinet shops where the old conservative cabinet-maker will use possibly a few pounds of glue every week. This glue is kept in an old-time glue pot (having a hot water container) and whenever the cabinet-maker requires glue, it is placed on the back of a stove, the water heated and the glue dissolved. No thought is given to the exposure of the glue to dust, etc. The brushes are dirty, the skin forming on the surface of the pot gradually accumulates and slowly decomposes. This may or may not fall into subsequent melts, thus contaminating them.

It is possible to save considerable of the accumulation and to work it up to good advantage in veneering. Detach scraps of dried glue adhering to the glue pot, cooker or glue spreader, examine them. If clean, place them in a kettle or cooker. After thoroughly cleaning, and removing all particles of glue, soften the selected pieces by means of heat, after adding a sufficient amount of water. You may also do this to dirty scraps, but it is best to re-heat them in a separate cooker, permit the dirt to settle and the supernatant glue may be used without risk. Should the glue, however, be sour, it is necessary to throw all pieces away. Remember, Mr. Reader, that glue is extremely sensitive to impurities. Cultures of germs are grown by bacteriologists in gelatine glue because they afford an ideal breeding place for germs. Keep your cookers, glue pots and spreaders clean.

Bone Glues

There are a few manufacturers who will buy bone glues for veneering because they are cheap. Bone glues do not have the binding quality nor the lasting quality of hide glues. Climatic changes will soon weaken joints made with bone glues and no matter how dry your lumber and thoroughly the pieces were jointed, it will open. There are now many lines of trade where the use of bone glue is imperative to secure the thorough class of manufactured goods that modern merchandising demands. However, as stated, the furniture manufacturer should not use them.

Several furniture and piano factories are using mixed hide and bone glues. The jobber or manufacturer will take a certain percentage of very strong hide glue and mix with bone. Good results have been reported. One of the largest jobbers doing this has requested the writer to make some tests and report results. Have been too busy to do much work in my laboratory and do not intend to express an opinion until I have made thorough physical tests.

Some manufacturers will buy one grade of glue, using it for veneering as well as joint purposes, gluing oak, pine, mahogany and an endless lot of other woods with the same glue, using the same proportions of water and glue,

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