.......American-Machinist--------------October-13-1892

 

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A JOURNAL FOR MACHINISTS, ENGINEERS, FOUNDERS, BOILER MAKERS, PATTERN MAKERS AND BLACKSMITHS, 
VOL.' 15, NO. 41. WEEKLY. 
NEW YORK, THURSDAY, OCTOBER 13, 1892. 


3.00 per Annum, ( SINGLE COPIES 6 CENTS 
COPYRIGHT 1892, BY AMERICAN MACHINIST PUBLISHING COMPANY. 
Twenty-ton Rope-driven Traveling Crane. 
The accompanying cut represents a twenty-ton traveling crane built by Alfred Box & Co. , Philadelphia, Pa. This style of crane has a number of pecu-liarities and radical departures from the older designs usually employed in cranes of this class. In the first place, it will be noticed the head gear is stationary and placed at one end, and in its frame are contained all the friction wheels and mechanism to operate the movements of the crane. This is entirely inclosed in sheet-iron case (not shown in cut), and yet is easily accessible by doors on top; this practically excludes the dirt from the vital parts, while the other journals are pro-vided with well-covered bearings and roller bushings. Power is conveyed to the grooved sheaves by 1f" rope, which is crossed and encircles the wheels about two-thirds of their circumfer-ence, these in turn driving two shafts; keyed on each are three grooved friction wheels. These shafts revolve in opposite directions, and between and slightly below them are three similar grooved friction wheels which 
For Sale Everywhere by Newsdealers. ENTERED AT POST OFFICE, NEW YORK, AS SECOND CLASS MATTER. 
stop motion to prevent running it beyond its limit. The bridge is designed to give ample strength and allow plenty of room for large trolley wheels, and each. girder is well secured together by diagonal bracing, making the whole structure very rigid and capable of standing severe strains and rapid motion. A dropped platform is provided when desirable, and the hand-wheels are placed below the bridge and geared to the upper screw shaft. The hook has a ball gearing and swivels easily with the heaviest load. All sheaves 


Proceedings of the Mechanical Section of the American Association for the Advancement of Science — Rochester Meeting. 
EXHIBITION AND DESCRIPTION OF COMBINED YARD AND METER STANDARD BAR. 
BY WM. A. ROGERS, WATERVILLE, ME. 
The bar exhibited is of Jessup steel, one face of which is brought to a true surface with the points of support placed at certain 

-SMITH BROS.EHILA. 
produce a uniform effect along the bar. The grinding substances used were several grades of washed emery, washed savorine, and finally rouge. The bar is graduated directly from a standard bar, the errors of which are known, so that corrections may be made in marking the new bar. To show the extreme delicacy required in such work, Prof. Rogers stated that a correction had to be applied, to allow for the influence of the heat radiated from the body of the operator on the nearest bar. This correction is de-termined by previous experiments, and is, in a measure, proportional to the time of ex-posure. In graduating the bar exhibited, a slight error was involved in some of the graduations, because before making them the operator had taken exercise which caused him to perspire freely, so that, instead of the bar nearest the body becoming heated, it had been slightly cooled by evaporation, and the corrections were thus thrown in the re-verse direction. A table of corrections ac-companies the bar, giving in eats case the number of parts in one million of the entire length of the bar that the graduations are in error. 776 of the 1,000 mm. divisions have an error not exceeding one twenty-five
'

and betAn and slightly below them are three similar grooved friction wheels which 
in error. 776 of the 1,000 ram. divisions have an error not exceeding one twenty-five-

are mounted in a sliding frame, operated by screw and hand-wheel ; by this means the center wheel is drawn or forced into either of its companion wheels, thus causing any mo-tion of the crane to be reversed or stopped at the will of the operator, and the whole op-eration is handled by simply turning either of the three hand-wheels to the right or left, thus avoiding a large number of complicated levers. The center frictions are geared to-cross-shafts leading to drum, bridge and racking motions. It will further be seen that the drum is placed above the bridge, per-mitting the trolley to pass under, thus giving it full sweep from end to end of bridge The trolley is also provided with automatic \


ROPE-DRIVEN TRAVELING CRANE. 
have roller bushings and work well without oil, which is important in foundry work, where excessive heat and dirt clog and dry up oil. The manufacturers have given spe-cial study to produce cranes that will meet all requirements for this class of work, and we are informed have met with good success in this line. 
Young men who have an idea of pursuing a course of study in some one of the excellent schools of mechanical engineering in the country should write for a catalogue. We are led to make this remark from a consider-ation of the amount of knowledge these cata-logues furnish. 

distances from the ends. The graduations are marked directly on the finished surface, which is protected from corrosion by means of a thin coating of vaseline. To obtain a true surface the bar was first planed, and then tested with a surface plate. The high portions were either scraped down or re-duced by means of a small lead lap. After this was done, a wax lap, which was first made true by testing with a surface plate, and scraping down the high places, was em-ployed to finish up the, surfaces. On the surface of the wax lap grooves were cut crossing each other, so that the surface is divided into small rhomboids, it having been found that this was necessary in order to 
thousandths of an inch. This degree of accuracy has only been attained by suc-cessive approximations. The standard yard was originally compared with the imperial yard of Great Britain, and the meter with the Meter de Archives of Paris. The error of total length of both yard and meter is known to within one, or, at the most, two twenty-five-thousandths of an inch. To determine the error of the subdivision of the scale, the method of slops is em-ployed. This consists in placing two stops so that the sliding table of the dividing en-gine, which carries a microscope containing a cross-bar, travels approximately a certain number of divisions of the scale in being 

 
 



 

is

cones or gears. The saw runs between hardened !steel plates filled with dogwood plugs, with the end grain in contact with the saw, and each plate can be accwately adjusted by a single screw. The back of the saw has a bearing 14- inches long on the beveled edge of a conical roller of a special composition, harder than steel. What little wear does occur takes place across the full width of the beveled surface, and therefore does not form grooves, as would be the case with a plain roller. The upper guide is counterbalanced, and is adjustable vertically by a hand-wheel. This hand-wheel, the lever for controlling the feed, the hand-wheel for setting the feed rolls, and the scale showing to what thick-ness they are set, are all readily accessible from the sawyer's usual working position. The upper wheel has a rim of bent ash with sted spokes, and the lower one is a heavy iron casting. The lower wheel being thus much the heavier, it acts as a by-wheel to pre-vent sudden and violent fluctuations of speed, as in starting and stopping, and thus prevents the overrun-ning of the upper wheel, which, being lighter, is capable of following the motion of the lower one without causing the saw to slip or to become slack on the working side. The rims of both wheels come upon a vertical line, which is considerably with-in the outer ends of the bearings, so that the shafts are well supported with-out the necessity for using outside bearings. T h e upper shaft can be angled while in motior. An adjust( ale spring maintains a proper tension on the saw, and renders it much more secure against breakage than the weights, commonly used for this purpose, as the inertia- of weights prevents them from yielding quickly enough when a chip gets between: the saw and tai,sawdust, rim. 


'NEW RE-SAWING MACHINE. 
and discharge them beyond ..thetto eauseip belt to shift easily. Height of ma-The lower wheel is kept free from chine, 10 ft. 7 in.; width of machine, 7 ft. 5 accumulations of sawdust by a scraper, and in. ; depth of machine, 6 ft. 5 in. ; weight the upper one by a brush. complete, 7,000 lbs ; diameter of wheels, 60 
'the spindle being 2i" diameter, and the bearings 2#" long. The end of the spindle is threaded for face-plates or chucks, and there is a draw-bar which extends through the spindle for holding split chucks which vary in size from A-" to 4-", the rods extend-ing through the spindle, which has a hole through it diameter. The cone has three steps for a 1/.." belt, the smallest step being 3" and the largest 44-" diameter. The flange at the rear end of the cone is drilled and provided with a pin for indexing. The foot-stock spindle is also of steel, hardened and ground, 1" diameter, and with a bearing 5.' long. The lathe swings over the bed 8", and takes between centers 18". The slide rest, which is shown on .page 2, Fig. 4, fits over the sides of the block, on which the T-rest is placed in Fig. 2. It has two circular graduated bases and two slides, the lower one of these being always at right angles to the center line of the lathe, so that a squaring or facing cut can be taken at any time when boring or turn-ing taper without disturb-ing the adjustment of the rest. The various binding arrangements are efficient, operating to hold the parts very securely with very light pressures. The tool holder is an eccentric device by which the tools are readily brought to the center or otherwise adjusted, and it is especially arranged with a view to enabling the tool ,maker ty make his own tools where the services of a blacksmith or tool dresser are not at command, as is often the case where such lathes are used. The lower

 
RIVETT BENCH LATHE. 
The body is a box-shaped casting, in one piece, very strong and rigid, and it can be placed on any good floor without a special fo(lthdation. 

inches; driving pulley, 22 to 30 in. d':ameter, as ordered, for an 8-in. belt; spew 450 to 525 turns per minute, accordin- and width of lumber; thielz—
or cross-slide has a move-ment of 4" and the nu, slide 5". At Fig. 5 is shown a block which clamps to the bed in the usual way, thes.,,, upper portion of this block swiveling in a horizontal plane upon a graduated base. The left-haa side of this block as shown jr the engraving is'adapted to receive th( 



 

drillpti

cones or gears. The saw runs between hardened !steel plates filled with dogwood plugs, with the end grain in contact with the saw, and each plate can be accwately adjusted by a single screw. The back of the saw has a bearing 14- inches long on the beveled edge of a conical roller of a special composition, harder than steel. What little wear does occur takes place across the full width of the beveled surface, and therefore does not form grooves, as would be the case with a plain roller. The upper guide is counterbalanced, and is adjustable vertically by a hand-wheel. This hand-wheel, the lever for controlling the feed, the hand-wheel for setting the feed rolls, and the scale showing to what thick-ness they are set, are all readily accessible from the sawyer's usual working position. The upper wheel has a rim of bent ash with sted spokes, and the lower one is a heavy iron casting. The lower wheel being thus much the heavier, it acts as a by-wheel to pre-vent sudden and violent fluctuations of speed, as in starting and stopping, and thus prevents the overrun-ning of the upper wheel, which, being lighter, is capable of following the motion of the lower one without causing the saw to slip or to become slack on the working side. The rims of both wheels come upon a vertical line, which is considerably with-in the outer ends of the bearings, so that the shafts are well supported with-out the necessity for using outside bearings. T h e upper shaft can be angled while in motior. An adjust( ale spring maintains a proper tension on the saw, and renders it much more secure against breakage than the weights, commonly used for this purpose, as the inertia- of weights prevents them from yielding quickly enough when a chip gets between: the saw and tai,sawdust, rim. 


'NEW RE-SAWING MACHINE. 
and discharge them beyond ..thetto eauseip belt to shift easily. Height of ma-The lower wheel is kept free from chine, 10 ft. 7 in.; width of machine, 7 ft. 5 accumulations of sawdust by a scraper, and in. ; depth of machine, 6 ft. 5 in. ; weight the upper one by a brush. complete, 7,000 lbs ; diameter of wheels, 60 
'the spindle being 2i" diameter, and the bearings 2#" long. The end of the spindle is threaded for face-plates or chucks, and there is a draw-bar which extends through the spindle for holding split chucks which vary in size from A-" to 4-", the rods extend-ing through the spindle, which has a hole through it diameter. The cone has three steps for a 1/.." belt, the smallest step being 3" and the largest 44-" diameter. The flange at the rear end of the cone is drilled and provided with a pin for indexing. The foot-stock spindle is also of steel, hardened and ground, 1" diameter, and with a bearing 5.' long. The lathe swings over the bed 8", and takes between centers 18". The slide rest, which is shown on .page 2, Fig. 4, fits over the sides of the block, on which the T-rest is placed in Fig. 2. It has two circular graduated bases and two slides, the lower one of these being always at right angles to the center line of the lathe, so that a squaring or facing cut can be taken at any time when boring or turn-ing taper without disturb-ing the adjustment of the rest. The various binding arrangements are efficient, operating to hold the parts very securely with very light pressures. The tool holder is an eccentric device by which the tools are readily brought to the center or otherwise adjusted, and it is especially arranged with a view to enabling the tool ,maker ty make his own tools where the services of a blacksmith or tool dresser are not at command, as is often the case where such lathes are used. The lower

 
RIVETT BENCH LATHE. 
The body is a box-shaped casting, in one piece, very strong and rigid, and it can be placed on any good floor without a special fo(lthdation. 

inches; driving pulley, 22 to 30 in. d':ameter, as ordered, for an 8-in. belt; spew 450 to 525 turns per minute, accordin- and width of lumber; thielz—
or cross-slide has a move-ment of 4" and the nu, slide 5". At Fig. 5 is shown a block which clamps to the bed in the usual way, thes.,,, upper portion of this block swiveling in a horizontal plane upon a graduated base. The left-haa side of this block as shown jr the engraving is'adapted to receive th( 



 

pg-2 AMERICAN MACHINIST  Oct-13-1892
moved from one stop to the other. The number of divisions selected must be an exact divisor of the total number into which the scale is divided. The scale is tested by adjusting the cross-hair of the microscope directly over one of the divisions, while the sliding table is against one of the stops, after which the table is moved until the second stop is reached. If the stops are set precisely in the correct position, and the scale is without error, the cross-hair of the microscope would fall directly over the mark on the scale, but, ordinarily, the cross-hair will not fall over the line, and the amount of deviation is measured by a micrometer. Each succeeding portion of the scale is gone over in this way. After the entire scale is gone over, the sum of the micrometer read-ings is taken, and that portion of the error due to setting the stops eliminated by sub-tracting the mean value of the corrections from each. This gives the relative error of each successive subdivision; to obtain the accumulated or total error reckoned from the initial point we sum the series. In the case of the meter scale, the error of the middle graduation was first determined, and the errors for the decimeters worked over until the error for the middle division came the same by the two methods. The discussion of this paper was mainly in regard to the difficulty of obtaining a perfectly true surface. Mr. J. A. Brashear stated that in special cases he had spent several weeks in making a plan surface for optical purposes two inches wSeveral other members pres-ent gave' t views in regard to the proper methods of grinding to a true surface. Prof. Rogers replied that he did not strive to obtain a mathematical true surface in his bars; his test was to move a microscope, used '"oheoglin testing the graduations and having a high magnifying power, along the face of the-bar; if this ritmained in focus, he considered the s accurate enough for his purpose.

 
-10°18 USE OF LONG STEEL TAPES IN 
so that by no means could the operators overstrain the tape. Temperature observa-tions were made in each case, three special thermometers being used w, {`h blackened bulbs, so that the surface had approximately the same radiating power as the tape. It was proved by the comparator that, with ordinarily careful handling, there was no variation in the length of the 100 meter tapes after long use. To test the efficiency of the steel tapes when used in the field,'A kilometer was measured by means of the iced bar, and this kilometer used as a stand-ard. It was found that the probable error of a single measurement of this kilometer by means of the steel tapes was about one part in 500,000, and that the probable error of the average of a number of observations was about one part in 1,500,000. So that the general conclusion arrived at is, that for measuring base lines, steel tapes, as standard-ized by the iced bar comparator, will give ample accuracy. The time required to make duplicate measures of the kilometer with the tapes is about one hour, and in spe-cial cases it was measured in one direction in twenty minutes. The method of measuring the standard kilometer by means of the iced bar apparatus, and probable error of the total length, was given in another section of the society, but as it is of interest in connec-tion with the present paper, the following table is here given, which compares the probable errors involved, with the results ob-tained by previous workers in the same line : 

bar; if this litrained in focus, he considered the Su accurate enough for his purpose. 
ON " USE OF LONG STEEL TAPES IN MEASURING BASE LINE. REPORT OF U. S. C. AND G. SURVEY. 
BY R. S. WOODWARD, WASHINGTON, D. C. 
A method of standardizing steel tapes by means of an iced bar comparator was first described, after which numerous experi-ments were presented that showed the error involved in using such tapes in measuring a base line one kilometer long. The iced bar employed in the comparator consists of a bar of steel, on which are lines five meters apart, at a temperature of 32 degrees Fahr. To preserve the bar at this temperature it is surrounded by ice. The whole is mounted on a carriage that travels on a small railway. In measuring off the length of the com-parator, which in most cases was 100 meters, the cross-hairs of two microscopes were first made to coincide with the lines on the bar. The bar was then moved forward, and the mark on the end nearest the starting point placed under one of the set microscopes. A third microscope was then set over the end away from the starting point. The micro scopes were mounted on wooden posts. At the ends of the comparator two stones arc solidly imbedded in the earth. In each of these stones a rounded brass projection is imbedded, to mark the ends of the com-parator. To place the microscopes directly over these end points a special device con-taining a level is used. Having obtained the proper setting of two microscopes that are the length of the comparator apart, the tape is held under them in a way that was found to be the most convenient and reliable in field work. Stakes are set ten meters apart along the line to be measured, and in the side of these round steel wire nails are driven. The tape is supported on these nails. The corrections necessary to apply, if the posts are set at a greater distance, as in crossing a stream, can be easily computed from data furnished by preliminary experi-ments. The tension of the tape was made the same, about 25 pounds in all measure-ments, by means of a spring balance at one of its ends, a breaking piece being inserted, 
quarter that of any other method presfiously adopted. The greatest source of error was found to be the difficulty of determining the tempera-ture of the tape correctly. It is generally supposed that a cloudy day is preferable for measuring with steel tapes, but the experi-ments indicated that such was not the case. The best time was found to be in the evening, while dew was being deposited.. Prof. Rogers stated that he agreed with Mr. Woodward that the temperature ele-ment was the greatest source of error in measurements of length. In his opinion the exact results obtained with the tapes was due to the fact that they were of a small mass, and partook readily of the same tem-perature as the air. Prof. S. W. Robinson gave a description of the method employed in measuring a base-line in the ordinary way. A clearing is pre-pared and graded as carefully as a railway bed, and the apparatus employed is very bulky. He also mentioned another methed that he had employed some years ago, of measuring with a steel piano wire having circular pieces fastened on it at the measuring points. Around the circular pieces V-shaped grooves were cut. In using the wire the circular pieces were held against ordinary surveying pins. If the operator happened to pull too hard on the wire while it was be-ing held against the pin, the form of the groove was such that the circular piece would slip by the pin without tending to displace it. This method was recommended only where moderate accuracy is required. 

 

Launch of the Cunard Twin-screw Steamer " Campania." 
In regard to the launch of the steamer " Campania," the London Engineer of September 29th says : Yesterday was performed at Fairfield Yard, on the Clyde, a feat the equal of which in its way has not been attempted since the Great Eastern " was put into the Thames at Millwall, thirty-five years ago. The Cunard steamer " Campania "—the first of the two intended Atlantic record breakers —was launched shortly before 2 P. M. into the sewer or unsavory canal upon which has been brought the wealth of the city of Glas-gow. Brunel launched his monster ship sideways because of her great length, and was we forget how many days in completing his task; but the builders of the " Cam-pania " have launched their 600 feet of steel structure stern foremost into a river which, measured in the direction of the launching ways, is only 900 feet across. Mr. R. Saxon White, the manager of Fairfield Yard, is to be congratulated upon the courage, foresight, and skill which he has displayed, and in the success which he has achieved. Looking from the deck of the " Cam-pania," shortly before she was released, it appeared an impossibility to slide 9,000 tons weight of steel structure, measuring 600 feet in length, into so narrow a stream without accident. And yet the feat has been accom-plished. Moreover, nobody at Fairfield seems to have ever experienced a doubt upon the subject, so thoroughly was every detail thought out and planned from the first, and so carefully was every step in the work at-tended to as it progressed. The cradle and ground ways were commenced several weeks ago, and , indeed, were practically completed on the occasion of the recent visit of inspec-tion of Lloyd's Registry Committee to the-

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AMERICAN MACHINIST-- Oct-13-1892   pg 3

 Clyde. Only a pair of ground ways were used, the breadth of each being, however, sufficient to leave but a fairly moderate weight per square foot of area when the structure was wholly resting upon it. The difficulty to be coped with was, in fact, not so much a minimizing of frictional resistance to the vessel's motion as that of gently and gradually, yet surely, stopping her motion when once she became fairly afloat. Never-theless, the sliding of 9,000 tons into the Clyde was in itself a task of no small magni-tude, and, in view of the fine form of the fore body, great ingenuity and care was necessary in order properly to support her bow extremity in the launching cradle. Of course for a long distance forward the only way to do this was to make full use of the edge laps of the shell plating; and as, in spite of the heavy scantlings of the " Cam-pania," these are necessarily very narrow, the poppets and other vertical supports needed careful fitting and efficient combina-tion. By an ingenious arrangement of wedg-ing, notching, and dovetailing, all this was very effectually accomplished, and there was no more interesting feature in the launching arrangements to the initiated observer than this device of Mr. White's for the purpose we have described. At the after end of the vessel—also very fine and clean—matters were rendered much simpler by reason of the peculiar form of the structure for hous-ing and carrying the twin-screw shafting on each side. The screw shafting in these ves-sels is wholly inclosed within the hull, there-by leaving nothing unsupported, and conse-quently providing against such deflection as contributed to disaster in the " City of Paris." The " wings " thus formed afforded excellent support to the long range of aftermost pop-pets extending to the propellers. The launching ways were greased and " turned in " a week before the date fixed for putting the " Campania " into the water, the interval being fully occupied in replac-ing the previously prepared and fitted parts of the cradle. The river, too, had been care-fully dredged during the same time, so as to form a hole of the requisite length, breadth, and depth for the vessel to float in and be 
was no luncheon or speeches. The owners think it will be time to talk about the ship when she has done something of which to boast. Several months of hard work remain to be performed before the " Campania " will be ready for her steam trials. Her engines, boilers, funnels, uptakes, and steam pipes are all ready to drop into their places; and the joiners' work is well advanced. Proba-bly by the beginning of March she will be a completed vessel—a credit to her able build-ers, and, we trust, a source of profit to her enterprising owners. It is to be hoped—and indeed expected—that her speed will be such 
New Water Rolling-mill. 
The cut shown herewith represents a roll-ing-mill with ater connections, which has been carefully designed for the purpose of rolling flat wire, watch and clock springs, or similar work that comes within the range of the machine. The rolls in this mill are made of the best Krupp cast-steel, and are hard and sound, with the finest lap finish on face. The arbors are made of tool steel, with hole running through to admit of the free circula-tion of water. The water enters one end of the top arbor, circulates through the arbor, and by means of the water connection, shown 

SPECIAL MILLING CUTTER. 
as to still further materially shorten the time distance between these islands and the United States. The sister vessel " Lucania " is being plated, and appears to be rather more than two months behind the vessel which was. launched yesterday. 
A Special Milling Cutter. 
We present herewith an illustration of a gang of milling cutters made by the Ingersoll Milling Machine Co. ,of Rockford, Ill. These cutters were made for milling the guides of a Corliss engine, and a block which was milled in testing them was photographed with the cutters, and is shown by the engraving. The radius of the circular portion of the cut 
at the left of cut, is conducted to and through the lower arbor, thereby keeping the rolls and arbor journals cool, which insures ac-curate rolling running at high speed. The roll journal boxes are copper and tin. The shafts are made of the best hammered steel, and all gears are accurately cut from the solid stock. The mill, in construction, is very powerful, being geared 30 to 1, which makes it, for rolling flat wire or springs, a desirable machine. The adjusting screws in frames, as shown, are accurately cut, and on these screws there is an adjustable collar, which is graduated to read .001". The weight of the machine is about 2,000 pounds. It is built by Blake & Johnson, Waterbury, Conn. 

paper wood than it is to file iron any more than absolutely necessary. When the pattern reaches the foundry there is not usually much danger of impress-ing too strongly upon the mind of the molder what the casting is to be used for, and that it shoull be of good quality iron, very smooth, and free from all imperfections. All precautions mentioned thus far will be amply repaid, for it is a tedious job to file and scrape away on faults which might easily have been :avoidedlin the pattern room or foundry. The next thing is to scrape aL.) d'•,le the casting smooth, and make necessary holes for draw:irons. The word smooth can be taken with a somewhat flexible meaning, according to what the job is, for on small pieces they should be finished up very nice and bright, while on much larger work, if it is brought down to a good surface free from bunches, even if not perfectly bright in every part, it will do, for the substance used for a filling which is afterwards applied will bring out a very even surface. As molding sand will stick to bright iron, the pattern must be coated with some pre-ventive, and perhaps the commonest way of all is to simply heat it and then hold a lump of beeswax in the hand, rub it all over the warm casting, and then wipe off the superfluous wax with a piece of waste or rag. If this method is adopted, it is very much better to first thoroughly rust the pattern be-fore heating. Sometimes the casting to be used as a pat-tern is blued instead of rusted, that is, heated quite hot, enough so that it turns a bluish color, and then afterwards covered with beeswax. Another method of finishing is to wipe them over with "blue water," which is done in this manner. Procure at the druggist's some lumps of blue vitriol and a little nitric acid, and take some of the vitriol, say a couple of ounces, and pound it to a powder, and pour it into a bottle holding about a pint, after which fill with water and about a tea-spoonful or so of the acid, and shake the mixture thoroughly until all is dissolved. This is used a great deal by machinists on 

 Lau-ing the Meviously prepared and fitted parts of the cradle. The river, too, had been care-fully dredged during the same time, so as to form a hole of the requisite length, breadth, and depth for the vessel to float in and be turned into the fitting-out basin of the com-pany. In this latter spot the wharf has been lengthened by extensive pilings, so as to ac-commodate a vessel of such huge dimensions below the sheer legs used in lifting the boilers and machinery into their places. To check the " Campania," Mr. White employed eight heaps of chain cables—four on each side—the collective weight of the cables being between 500 and 600 tons. These were simply dragged by the vessel over the ground, their weight and frictional resistance affording the only means of stop-ping her when afloat. By using heaps of chain cables in this way, Mr. White availed himself of two forms of resistance. In the first place, when moved by the vessel the component parts of each heap of chains ad-justed themselves until the whole body was in direct tension, and in this manner a gentle buffer-like force was brought to bear upon the checking cables, preparatory to the greater resistance offered by the drag of the whole body of chain upon soft or uneven ground. Two of the cables passed through the hawse pipes on each side, and other two were shackled to two substantial plates riveted on each side of the vessel at locali-ties which were stiffened on the inside by the presence of bulkheads and longitudinal stringer girders. It will thus be seen that in attacking the problem of putting the " Cam-pania " into the Clyde, the Fairfield Com-pany took every precautionary measure which long experience in launching huge steamers could suggest, and the success of the operation confirms the wisdom of all that was done. The ceremony of naming the vessel was performed by Lady Burns, wife of Sir John Burns, Bart., of Wemyss Castle, and the subsequent proceedings were of a wholly informal character. The launch was witnessed by a large body of spectators, the yard gates being thrown open to the public, and platform accommodation being provided at the bow of the vessel for three hundred privileged friends of the company. There 
 The radius of the circular portion of.the cut 

 puwuci, and pour it into a bottle holding about a pint, after which fill with water and about a tea-spoonful or so of the acid, and shake the mixture thoroughly until all is dissolved. This is used a great deal by machinists on smooth surfaces where they wish to lay out work with dividers or scratch-all, but it also makes a nice surface for a pattern, which will draw easily from the sand, and if the pattern has been worked down to a bright surface all over it will answer with nothing further being applied, for it instantly deposits a sur-face of copper everywhere the solution comes in contact, provided the work is en-tirely free from grease or oil. This must be remembered, and any grease spot carefully cleaned. This is easily done by wiping over with hot Water or rubbing with chalk. An additional coating of the mixture of black lead, beeswax and turpentine, which a contributor to the AMERICAN MACHINIST described some time since, gives the pattern a smooth, slippery surface, by warming it and applying the preparation and then wiping off the superfluous covering while it is still hot. On work where. not so much labor has been expended in the finishing with file and scraper, and the parts are not quite smooth, I can recommend the following to give a very satisfactory result, although it takes a some-what longer time. First wipe the casting over with the blue solution; this gives a copper surface on all the bright parts, but does not do much good on the rougher portions, so melt some bees-wax and stir in the black lead until it is the consistency of dough, and thin with turpen-tine till of the thickness of paste. Next warm the pattern and give it a good coat all over with the preparation, and put it away until cold. This acts as a filling, and it is then necessary to scrape it carefully off again to obtain an even surface. A putty knife blade held quite flat does very well to remove what is unnecessary, and what is needed remains and hides any rough-ness of the pattern. Lastly, rub it carefully over with very fine sandpaper, taking care not to remove the copper surface at any point. I have found a steam glue heater an ex-cellent place to mix up the preparation and 


BY JOHN M. RICHARDSON. 
Many an iron casting intended for a pat-tern would stand much higher in the opinion of the man about to finish it if its ancestry was traced back one generation to the master pattern, and this progenitor of a race of num-berless offspring was constructed with a little more care, especially with regard to its lines and curves, taking pains to have them true and not just enough out so that they are ever afterwards an eyesore to a close observer. The draft must be carefully attended to also, for it is vastly easier to plane and sand-
t.J1. Vuul Gam, ULLU I1/U.11U L puwuci, and pour it into a bottle holding about a pint, after which fill with water and about a tea-spoonful or so of the acid, and shake the mixture thoroughly until all is dissolved. This is used a great deal by machinists on smooth surfaces where they wish to lay out work with dividers or scratch-all, but it also makes a nice surface for a pattern, which will draw easily from the sand, and if the pattern has been worked down to a bright surface all over it will answer with nothing further being applied, for it instantly deposits a sur-face of copper everywhere the solution comes in contact, provided the work is en-tirely free from grease or oil. This must be remembered, and any grease spot carefully cleaned. This is easily done by wiping over with hot Water or rubbing with chalk. An additional coating of the mixture of black lead, beeswax and turpentine, which a contributor to the AMERICAN MACHINIST described some time since, gives the pattern a smooth, slippery surface, by warming it and applying the preparation and then wiping off the superfluous covering while it is still hot. On work where. not so much labor has been expended in the finishing with file and scraper, and the parts are not quite smooth, I can recommend the following to give a very satisfactory result, although it takes a some-what longer time. First wipe the casting over with the blue solution; this gives a copper surface on all the bright parts, but does not do much good on the rougher portions, so melt some bees-wax and stir in the black lead until it is the consistency of dough, and thin with turpen-tine till of the thickness of paste. Next warm the pattern and give it a good coat all over with the preparation, and put it away until cold. This acts as a filling, and it is then necessary to scrape it carefully off again to obtain an even surface. A putty knife blade held quite flat does very well to remove what is unnecessary, and what is needed remains and hides any rough-ness of the pattern. Lastly, rub it carefully over with very fine sandpaper, taking care not to remove the copper surface at any point. I have found a steam glue heater an ex-cellent place to mix up the preparation and 

4 AMERICAN MACHINIST 
keep it hot, and there is no danger of igniting the turpentine, as there would be over a flame. Finally I will mentioP  , ol„ process, which, for pati,rns that have been finished to a nice even surface to start with, is superior to others, in my opinion. Bayberry tallow is a vegetable product, found as a film or blush on the outside of bayberries which ripen on low bushes in the autumn, and is separated from them by boil ing, they tallow then rising to the surface. When cold it is much harder than beeswax and somewhat lighter in color, having an aromatic odor and feeling very slippery to the touch. uses are quite varied, and it can usually be f, and in drug stores. To prepare it for use on patterns, melt it, adding enough turpentine so that when cold again it will be about the consistency of butter. The pattern should be first rusted or else covered with the copper solution previously mentioned, and then rubbed over thoroughly with the tallow. This leaves an extremely smooth, shiny surface, and it is clean to handle and has the advantage that it is not necessary to heat the mixture after being once made, in order to apply it, or the pattern either, without one chooses; thus a pattern can be kept in fine condition contin-ually if a molder will provide himself with a can of the preparation, and keep it on his bench and occasionally rub over the pattern with it before going home at night, when the next day it will be found hard and ready for use, as the turpentine will then be evaporated. While I may not have offered anything very original, still I believe that some points will be helpful to many. As these are probably not all the ways nor the only ones in use, I shall not go so far as to claim any one of them to be the absolutely best method which can be devised. 
Pouring, Flowing-off and Feeding Cast-ings—II. 

BY S. BOLLAND. 
dle of the swiftly rotating mass, and just how this may be accomplished is shown at Fig. 18; where a number of castings, directly con-- —,;ted with a central ball, may be fed with comparatively pure iron, with no possibility of dirt other than may be gathered within 

Eig .23. A B pipes or‘columns at the flanges, the gates A A being intended when it is desired to run down through the cope, and the one at B to be used when it is thought that the former plan would be too hard on the mold at that point. 

Ely. 19. far metal will reach in such wor method of running long columns one end co, ,...icts with the first prince filling molds with iron of equal temp ture, it is very evident that all long castings should be filled from both ends. The wis-dom of the above always strikes us the more forcibly when we see any viola-tion of these principles result in a cracked casting. Keep all risers away from brackets ; for should there be but a very slight commotion in the mold the bracket is sure to suffer if the disturbance finds a vent at that point. When the flask will admit of running round columns at the end it is by all means the best plan to adopt, and the best kind of runner for this purpose is shown at Fig. 22, where main runners A A are seen to connect with a circular runner B, cut round the bearing and entering the casting at one or more gates ample to run the column safely. Round columns will run 18 feet inch thick from one end, providing all other things are favorable ; but the remarks on square columns apply with equal force to round ones, and risks should not be taken. Sometimes it is found advisable to change the location of the runner ; if this must be done, choose some flange or collar into which the gates can be directed either on the side, as seen at C, or dropped down at D. Fig. 23 shows how to run a large wheel through the hub core. The cen-ter dry sand core, with a hole large enough to fill the mold at a proper rate, rests on another dry sand core in which the requisite gates have been prepared. To save making the bottom core, holes for gates may be made at A, indicated by broken lines, but this plan is some-what risky, if the noses against which the iron beats are not made in dry sand, as seen at B. It is plain that a wheel filled after this manner is preferable to any other, as it makes what is otherwise a critical job a 

Fig. 18. 
AinAmerican Machinist _Fig. 21. 

Pouring, Flowing-off and Feeding Castings—II. 
rt 

BY S. BOLLAND. 
Fig. 16 (September 29) illustrates a system of dams set before the castings when it is de-sired to produce clean work from a spray. When best results are looked for, all such gates should be connected with the patterns on a match board, so as to insure a good hard surface for the molten iron to pass over. Gates cut with tools are, as before stated, un-trustworthy, on account of the soft, broken surface yielding to the extreme heat to which they are subjected, and thus forming slag that invariably finds its way into the casting. - The form of the leader, in this instance, is a noteworthy feature; the iron entering at A travels rapidly along the smooth, round sur-face of the leader, passing the gates and out at C, carrying a large proportion of the dirt along with it; whatever portion remains is held on the upper surface of the leader whilst the casting is being fed from the bottom. The dams D, as seen, are formed with cores, and make "assurance doubly sure" by check-ing any inflow of dirt, should the pouring from any cause be lacking in force. There is no other casting that has helped the science of running as much as the gover-nor ball. During the early part of my ap-prenticeship this job was held back for some particular man who alone could be trusted with such an important job, and not unfre-quently have I known the best men to fail time after time to produce a casting that was clean all over when turned. The manner of running a ball which must be turned bright is shown at Fig. 17, where it is seen that the metal passes down A into the ball at B; the direction given the metal by this form of ingate causes the metal to re-volve rapidly in the mold, and this causes the lighter substances which gather on the sur-face to collect towards the center, as indicated by the arrows in the plan, to be ultimately ejected at the riser C. The principle involved to keep the ball clean must naturally suggest the propriety of filling other molds from such a ball whilst the dirt is being held a prisoner in the mid-

Fig. vo. _Fig. 22.  
_Fig. 25. 
Pig. 26 Fig. 28. POURING, FLOWING-OFF AND FEEDING CASTINGS. 
their own limits. Unless in large castings, there need be no riser on the ball when it is used for running purposes. Fig. 19 shows how the principle may be made general and used for almost any class of work. Fig. 20 illustrates two methods of running 
The regulation method of running square columns is shown at Fig. 21. All such col-umns will run from one end, under ordinary head pressure, 17 feet at one inch thick if the iron is in good condition ; beyond this it is unwise to go, especially if the column should be less than one inch. I speak now of how 
The ball shown at Fig. 25 is supposed to be 12 inches in diameter, and sup-pose that such a ball was cast (without riser) with hot iron, and left to cool in the same position it was cast; it is cer-tain that the upper surface would have fallen in, in proportion to the amount of shrinkage which would have taken place before the crust was firm enough to sustain itself; the amount of shrinkage would, of course, be according to the nature of the iron it was cast with. Now if this ball, when cold, was split in two, it would be found that the upper hemisphere would show a sponginess similar to that seen in the sectional illustration at Fig. 26. The figure 
by broken lines, but this plan is some-what risky, if the noses against which the iron beats are not made in dry sand, as seen at B. It is plain that a wheel filled after this manner is preferable to any other, as it makes what is otherwise a critical job a very safe one, and insures a good cast-ing every time, at least so far as the running is concerned. Fig. 24 is a plan and elevation of a spiral drum, or at least as much of it as will serve the purpose of showing how to arrange for a system of bottom gates when such gates must be made in the pit around a brick mold. Where the pits are damp it is absolutely necessary to have the gates protected from the moisture. The method shown needs no explana-B tion other than can be discovered by a careful examination of the figure. A A are the gates prepared in the mold, against which are set cores B B, these again being surmounted by other cores, as seen, until the top is reached. If the mold is unusually long, and there is danger of the metal becoming too sluggish to fill the upper parts of the mold correctly, then apply the gates on the top, after the manner as fully ex-plained in " The Iron Founder," page 163. The utility of feeding castings is questioned by some, but a little reflec-tion will, I am sure, lead all who deny its efficacy to see the erroneousness of their conclusions. 

 


pg-5  gouge, chisel and mallet are used to remove the bulk of the wood. As there is risk of the concussion of the blows splitting out the short grain, their direction should be rather diago-nally, and away from the rim outwards in the direction of the line A A, Fig. 62, and as more and more is removed, inclining to parallel. When the bulk of the stuff has been removed the curves of faces and flanks are set in a lit-tle way with paring gouge and chisel, and the edges whitened with chalk or reddened with red lead in oil. The flanks and faces are now worked straight across from one side to the other with paring gouge and chisel, and the setting in and coloring of the curves at the ends prevents risk of the lines being cut un der with the gouge and chisel. A small, thin, narrow straight-edge is used with coloring matter, to test the straightness of the flanks as the work proceeds—a quite essential pre-caution when the cutting is done with gouge and chisel, tools 'which do not possess the initial faculty of guidance possess( d by the plane. The plane, as we see, can only be used for the extreme faces, Fig. 63 A. When the teeth are worked accurately nothing more is done to them except to give them a good oiling with linseed oil with a brush or rag. This imparts a slight hard-ness and a good appearance to the surface. The marking out of bevel wheel cogs necessarily proceeds on different methods. Still there is no more actual difficulty, but only more time required with the latter. Since a bevel wheel is a frustum of a cone the tooth centers, roots, points, flanks, and faces all run in exact planes to the apex A of the cone, Fig. 64. The shapes of the teeth are marked out accordingly on the drawing from which the wheel is Made, and are transferred to the ends of the cogs. I need not go into the details of the operation, but the drawing, Fig. 64, will convey the whole , meaning of the process to the mind of a pat-tern maker. At B there is the sectional form of the tooth, and at C D the forms and di-mensions of their outlines on the large and small diameters respectively are seen pro-jected. The radii are not taken along the semi diameters a b c d, but along the project-ed radii e b, f 4, on lines at right angles with A e. These are then drawn at C D. The thickness of the cogs on the-small diameter is 
The small grooved pulley on the arm over which the slack side of the rope passes holds the rope up and causes it to encircle nearly the whole of the driving pulley, making it next to impossible for the rope to slip. It is manufactured by Albert L. Colburn, New Haven, Conn. 
Two-spindle Boring and Mortising Machine. 


This machine will bore two holes at once, 
between centers. Weight, abo-ut 500 pounds. Either of these machines can be furnished with hand-lever and a treadle. The manu-facturer is P. Pryibil, 498-510 W. 41st street, New York City. 
Two firemen who were on the steamer "Alice Blanchard " on a trip to the Yukon River brought back two novel Aleut canoes. The boats are made of rawhide supported by horizontal ribs The only opening is a circular hole in the center large enough for 
LETTERS FROM PRACTICAL MEN. 
Fly-wheels. Editor American Machinist : In the matter of fly-wheel diameter and weight, I like to apply Matthew Baldwin's old rule in locomotive construction : " Make it about right, and then throw in another ton of iron." With this it is suitable to remember J. A. Fay & Co.'s rule for horse-power to drive wood-working machinery: " A little too much belt power is about enough." ROBERT GRIMSHAW. 


SMALL PORTABLE DRILLING MACHINE. 
and the line joining the center of the two holes may be at any desired angle to the table, from horizontal, which is the position shown in the engraving, to the vertical, or where one spindle would be vertically over the other. The table can be set 10" below the centers of spindles. It slides .forward and back 
a man's body so that he can sit down. A flap of rawhide surrounds the hole, and when the occupant plants himself in the bot-tom of the craft he draws this flap up, fastening it tightly around his body under the arms. This makes the boat practically water-tight, and he can paddle along in the roughest kind of weather without danger of drown-
Why Are Gears Noisy ? Editor American Machinist : In reading " Gascon's Discourses Upon Some Shortcomings in Text-books," by Jarno, I am led to attempt to put a few thoughts of my own on the same subject be-fore the readers of the AMERICAN MACHINIST.

Take any of the text-books that are now published treating upon " Involute Gearing "—all give a theory of constructing the gear 8ooth, and gears so constructed fail to give good practical results. In fact, some will not mesh at all. What the average ma-chinist wants is this gear question discussed in plain, every-day talk. Most writers, in explaining the theory of gearing, use technical terms, which, while probably correct, are understood by but few of the mechanics having, anything to do with gearing. The writer is one of that class who repre-sent the practical side of gearing, and what I shall say will be the result of a long and varied practice. First, I will ask the professors a few ques-tions. Can they tell us what amount of interference there is in the true involute in a pair of gears, say 3 P 19 and 69 T, and can they tell how to draw the form of teeth for these gears so they will run smoothly and quietly?. Why do gears make a noise ? How should the teeth bear upon each other to prevent a noise ? Which gear is the best and smoothest run-ning—the 144-°, 18°, 20°, or 24° pressure angle, and why ? T 
 

 
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