CHAPTER XIII.

SOFT SOLDERING WITH THE MOUTH BLOW PIPE.

The common blow pipe is a simple little tool that is used in connection with an alcohol torch for soldering the finest and most delicate pieces of jewelry, and constitutes the sole method of soldering used by Britannia workers and jewelers, and the fact that such a varied assortment of articles are soldered by the blow pipe process leads one to surmise that it can be used to advantage on coarser work. Though it is a familiar tool to gas fitters, plumbers as a rule are ignorant of its use, and it is hard work to find one who ever saw a blow pipe used on lead work. It is an easy matter to become proficient in its use, and the trick of keeping up a steady blast, and breathing regularly at the same time, is soon learned, and, when once acquired, stays with you always. This trick consists of making a bellows of your cheeks and using your tongue as a valve to close the entrance to the throat, leaving the passage from the nostrils to the lungs clear for breathing purposes. The only things necessary to purchase for practice are a common bent blow pipe, which can be had for about 15 cents, and a common candle.

To operate: The candle should be lighted, and when it burns well and freely the tip of the blow pipe should be brought close to the flame and slightly above the wick, _a_, Fig. 45. Then blow lightly through the blow pipe, and a pointed clear blue flame from 1 to 2 inches long, which will burn paper or char wood at a distance of 6 or 8 inches from the flame, will be the result. The flame is hottest and best when it shows a perfect cone-shaped blaze, and is obtained by a very moderate blast. The variation of the blaze can be noted by commencing to blow very lightly and increasing the pressure gradually. The flame will then show all stages from a smoky flame to a long blaze that cannot be concentrated on any small surface. The little sharp tip is where the hydrogen burns, and is the hottest part of the flame, being the part that is used for soldering.

Now, having noted these peculiarities, and knowing the perfect flame by sight, we will proceed to acquire the steady blast. The blow pipe should be held between the lips, which will form a tight packing around it, and must not come in contact with the teeth. The cheeks are then inflated, which will have a tendency to throw the tongue back to the throat and prevent the air in the mouth from blowing out through the nose. Now, by contracting the cheeks, and throwing the tongue slowly forward, the air will be forced through the blow pipe. This action is assisted when exhaling air by the pressure of the lungs, but when inhaling air the muscular contraction of the cheeks is depended upon entirely for the blast.

The ability to keep up a steady blast is merely a trick, or knack, and is learned with a few hours' practice; when learned, the length of time that the blast can be kept up depends solely upon the strength of the muscles of the cheeks of the operator. If these did not tire, the blast could be kept up for an indefinite time. Having learned to keep up the steady blast and get a perfect flame, the beginner will want to practice soldering. The blow pipe method of soldering has for its range of work everything that can be soldered, from Britannia metal to platinum, but the only metals that are used by the plumbers are tin and lead and their several compositions, so we will confine ourselves to the study of those metals.

Kinds of Solder Used.

In soldering any metal the solder should be so proportioned that it will melt many degrees lower in temperature than the metal to be soldered. Otherwise it would be quite probable that holes would be burned in the work before the solder would melt. There are exceptions to this rule, however; for example, lead burning, where one piece of lead is fused to another. As also with Britannia metal, it can be, and is, soldered with its own material, but it would be likely to have holes burned in it occasionally, and to avoid this a solder mixed for that purpose should be prepared. Two receipts are given here for quick melting solders that are suitable for this work. The first is preferred, but the second will answer the purpose.

Solder No. 1: Procure 4 ounces of pure lead, 4 ounces of pure tin, and 2 ounces of bismuth. The lead should be melted first and thoroughly stirred and cleaned. It should then be allowed to cool to the melting temperature of the tin, which should then be added. Lastly add the bismuth. The whole should then be stirred and poured into a suitable mold into very thin strips, about the size of a No. 8 wire, making strips of solder that can be rolled up and carried in the pocket.

Solder No. 2: This solder is composed of two parts of tin and one part of lead. These should be mixed as described above. To have success in making solders several points must be observed. The metal melting at the highest temperature should be melted first, which must then be allowed to drop to the melting temperature of the next metal to be added, and when ready to pour into molds the mixture must be stirred, as the specific gravity of the several metals differs considerably, and unless constant stirring is resorted to the mixture will partially separate upon cooling, and the result is an irregular solder that will not do the work.

Practicing the Blowing.

Now, for practice, take two pieces of ¼-inch lead tubing and prepare them as for a cup joint, by spreading one end with the bending iron and rasping the other end to fit the cup, as shown in _a_, Fig. 33. Support them as you best can in an upright position. Flux the joint with rosin. Then take the solder in the left hand, set the lighted candle at the right hight and distance from the joint, as shown at B, Fig. 47, which leaves the right hand free to manage the blow pipe. Then heat the joint with the flame, and, as it gets hot, touch the joint with the solder, and when it reaches the melting temperature of the solder a drop of it will detach itself and flow clear around the joint, making a smooth, clean joint that is stronger than the pipe itself.

Joints made in this manner present a handsome and workmanlike appearance to the mechanical eye. Practice diligently on the lead pipe until you have become so proficient that you can flow the solder all through the joint without withdrawing the flame. Then procure some ⅜-inch block tin pipe, and, when that can be soldered perfectly, the beginner can consider himself sufficiently proficient to practice on flat seams on Britannia metal.

Soldering Britannia Metal.

For working Britannia metal the candle cannot be used, as the dripping grease will cover the work and seriously interfere with the flowing solder. The beginner must provide himself with an alcohol or kerosene torch. A good form of torch, manufactured and sold for electricians' use, is shown in Fig. 48. The alcohol gives a clean flame, but by comparison is somewhat expensive. The kerosene gives a flame that can be concentrated on a small surface with fully as much heat, and if care is taken to allow only the blue flame to touch the work, it is fully as clean and cheaper.

The burning kerosene torch gives off a dirty smell and smoke, which makes it disagreeable to handle, but this is a case of take your choice, and it is left to the beginner to use either, as they will both do the work satisfactorily. It is also necessary, in doing this work, to have the blow pipe attached to the torch and connected to the mouth with a piece of very small rubber tube. This will leave one hand free to apply the flux and hold the solder. The flame can also be quickly placed in any position or directed to any portion of the work without allowing the work to cool. The alcohol torch for this work should be so constructed that it can be held in a horizontal or inverted position without spilling the contents of the torch.

The handiest, as also the cheapest, torch to make is the one shown in Fig. 49. It consists of a can 3 inches high made in the shape of a frustum of a scalene cone. The tube B should be ¼ inch in diameter, and must run parallel with the flaring side and extend half way to the bottom of the can, as _e_. Then, when the torch is tipped to solder horizontal work, the alcohol will flow into the space _a_, leaving the alcohol to supply the wick to be drawn up by capillary attraction. This tube is made of ¼-inch brass tubing, bent to form an angle with the can, as shown.

A screw and cap with a seat, such as is used on brass lamps, is obtained, and a hole punched in the cap _c_ just large enough to receive the tube B. The screw is soldered into the opening of the can at D. The wick, which is formed of many strands of candle wicking rolled tightly together, is pulled through the tube by means of a wire hook, and left sufficiently long to lie in the space _a_, so that it will always lie in the alcohol. This tube is placed through the hole at D, and allowed to project about ¾ inch outside of the can. Wicking is then wound around the tube and forced into the socket formed in the screw D. The cap is then slipped over the tube at _c_, and screwed down tight on the wicking, which will make a tight joint at D, and will hold the tube firmly in place.

When necessary to fill the torch the tube can easily be removed and the torch filled. A separate filling screw can be used if desired. Even with this form of torch an excess of alcohol will occasionally get into the wick when used in a horizontal position and increase the size of the blaze. But when this happens the torch can be brought to an upright position for a moment, which will drain the wick and bring the blaze to its proper size.

The blow pipe for this torch is made from a piece of very small copper or brass tubing. The end intended for the tip should be bent to the angle required, as shown at _f_, Fig. 49. It should be fastened to the torch by means of a clamp, _g_, soldered to the flaring side of the torch. This clamp should be so arranged that the blow pipe can be adjusted to the requirements of the blaze. This clamp consists of a short piece of brass. A hole is drilled in one end to allow the blow pipe to pass through, while the other end is filed to fit the bevel of the can to which it is soldered. The blow pipe can be held in position with a wedge, or a hole can be drilled and tapped and a small screw inserted which will hold the blow pipe firmly in place. The tip of the blow pipe should not be larger than 1-32 inch. The rubber tube can then be attached to the projecting end of the blow pipe at _h_, which is then ready for use.

Owing to the Britannia metal melting at such a low temperature, it would be well for the beginner to practice on pieces of 2-pound sheet lead. Seams on this class of work are made by butting the edges of the metal, as these seams are not supposed to show. The seams are prepared by truing the edges and then beveling the edges with the shave hook so that when brought together a V-shaped groove is formed. This is then fluxed with a small amount of powdered rosin. A drop of the quick melting solder is then melted from the strip and allowed to drop on the seam. The flame is then applied to the sheets, and as the solder flows the flame must be kept slightly in advance of it, Fig. 50. Care must be taken to heat the sheets only enough to cause the solder to flow. Otherwise the seam will not appear full. The beginner should experience no trouble in soldering these lead seams, and when perfect control of the torch and flame is had, pieces of Britannia metal should be substituted for the lead. These seams are prepared and fluxed just as for lead.

Britannia metal is fast becoming the favorite lining for splash and drip boards on butler's pantry sinks, as also for lining the work benches in saloons. It is soft enough to allow the most delicate china to be laid on it without danger of chipping, and is also very easy to keep clean. It takes a high polish and always looks well. The method of cutting the metal for a butler's pantry sink is shown in Fig. 51, the dotted lines showing the actual dimensions of the article to be covered, while the full lines show the laps required to cover the edges of the board. This metal is harder than lead, and will not dress smooth with the dresser. Any uneven spots must be pressed down with a hot flatiron. The method of turning the edges is shown at _a_. The bending iron is heated and rubbed over the edge, gradually turning the edges until they are at their proper position. The iron must be constantly heated to insure the best results, and if properly done no wrinkles will appear. A lined work bench is also shown in Fig. 52, which shows the method of putting in the bar washer. The sheet metal must be cut and fitted to its place and all the seams possible should be soldered before placing the metal in position. The edges should be tacked on the under side of the work, when practicable, with copper tacks.

Sooner or later the blow pipe solderer will be called upon to make repairs on Britannia metal, and will be surprised to find that it will be impossible to solder the metal, owing to the excess of moisture under it. The best way to overcome this, which is practically the only trouble that occurs, is to cut out a small square patch. The edge can be cleaned and a patch of new metal carefully fitted into the hole. When ready to begin soldering, a piece of blotting paper should be inserted between the patch and board. This paper will absorb all the moisture and allow the seam to be neatly soldered. The man who makes himself familiar with the blow pipe and torch soon finds himself in a different class from the ordinary everyday mechanic, and if mechanical ability be accompanied with sobriety and stability, the possessor will always command a good steady income.

THE END.

INDEX.

Acid Chamber, Framing, 109

Acid Chamber Work, 108

Acid, How Applied, 66

Acids, 20

Action of Generator, 66

Addition of Acid, 66

Air and Gas, Regulating Volume and Pressure, 74

Air Holder, 40

Air Pressure, 58

Alcohol Torch and Blow Pipe, 133

Apparatus for Lead Burning, 15

Arsenic, Poisonous Flame, 69

Arsenic Released from Acid on Zinc, 69

Bellows Air Holder, 49

Blow Pipe, 50, 62

Blow Pipe, Kirkwood, 122

Blow Pipe, Mouth, 127

Blow Pipe Practice with Candle, 128

Blow Pipe, Walmsley Compound, 50

Blue Vitriol or Copperas, 56

Bottom for Generator, 35

Britannia Metal for Repairing, 140

Britannia Metal Soft Soldering, 132

Britannia Metal Work, 14, 31, 32

Britannia Metal Work with Torch and Blow Pipe, 132

Burner, Kirkwood Lead, 119

Burner Tips, 62

Burns and Their Treatment, 17

Candle Blow Pipe Practice, 128

Care of Apparatus, 68

Cautions, 16

Charging and Cleaning Screws, 26

Charging Generator, 64

Chemical Tanks, How Lined, 105

Chipping Knife for Lead, 110

Cleaning Generator, 67

Colors of Flame, 76

Connecting Apparatus, 55

Cup, Scrubbing, 56, 68

Cup, Scrubbing, How Made, 70

Cutting Heavy Lead Straight, 110

Explosions, What to Do When They Occur, 17

Fire Trap, 56, 68

Flame Management, 73

Flame Under Different Pressures, 74

Flat Butt Seam, 83

Framing Acid Chamber, 109

Gas from Gasoline, How Generated, 39, 51

Gas Pressure, 58

Gasometer Air Holder, 46

Generator, Charging, 64

Generator, Cleaning, 67

Generator Construction, 26

Generator Frame, 30

Generator Materials, 30

Generator Pipe, How Fitted, 37

Generator Seams, How Burned, 36

Horizontal Butt Seam, 88

Horizontal Lap Seam, 93

Hydrogen and Air, Effect of Mixing, 24

Hydrogen Apparatus, Special, 119

Hydrogen from Water, How Made, 25

Hydrogen Gas and Its Properties, 18

Hydrogen Gas, How Made, 20

Hydrogen Proved Lighter Than Air, 23

Illuminating Gas Burning, 51

Inverted Butt Seam, 90

Inverted Corner Seam, 98

Inverted Lap Seam, 92

Joint for Through Burning, 102

Kirkwood Blow Pipe, 122

Kirkwood Lead Burner, 119

Knife for Cutting Lead, 110

Lap Seam, 82

Lead Burning Explained, 10

Lead Headed Nail, 117

Lead Sheets for Tank, 105

Lining Chemical Tanks, 105

Mixing Fork, 55, 57, 59

Mouth Blow Pipe, 127

Nail, Lead Headed, 117

Pipe Seams, 100

Pressure for Working Gas and Air, 58

Repairing with Britannia Metal, 140

Round Pipe Butt Seam, 100

Round Pipe Lap Seam, 103

Round Pipe, Tee Joint, 104

Scrubbing Cup, 56, 68

Scrubbing Cup, How Made, 70

Seam, Butt, on Round Pipe, 100

Seam, Flat Butt, 83

Seam, Horizontal Butt, 88

Seam, Horizontal Lap, 93

Seam, Inverted Butt, 90

Seam, Inverted Corner, 98

Seam, Inverted Lap, 92

Seam, Lap, 82

Seam, Lap, on Round Pipe, 103

Seam, Through, on Round Pipe, 101

Seam, Upright Lap, 95

Seam, Upright Butt, 86

Seams, Different Kinds of, 80

Seams, How Prepared, 80

Seams, Pipe, 100

Sink, Bar and Washer, 138

Sink, Butlers' Pantry, 137

Soft Solder, 13, 130

Soft Solder Formulæ, 131

Solder, Soft, 13, 130

Special Hydrogen Apparatus, 119

Staging for Acid Tank, 115

Straps for Tank Lining, 111

Tanks, How Made, 12

Tee Joint on Round Pipe, 104

Test for Hydrogen, 21

Testing Apparatus, 56

Through Burning, Joint, 102

Through Seam on Round Pipe, 101

Tips, Burner, 62

Tips, Sizes of, 78

Torch, Alcohol and Blow Pipe, 133

Trap, Fire, 56, 68

Upright Butt Seam, 86

Upright Lap Seam, 95

Vitriol, 56

Vitriol Action on Zinc, 69

Walmsley Compound Blow Pipe, 50

Water Pressure Air Holder, 42

TRANSCRIBER'S NOTES

1. Silently corrected typographical errors. 2. Retained anachronistic and non-standard spellings as printed. 3. Enclosed italics font in _underscores_.