Preparing And Wiping Joints

When the writer first started to carry the tools for a plumber and to prepare joints for wiping, the remark was often heard that joint wiping would soon be a thing of the past. I have heard this many times since from many different sources. Personally, I fail to see the passing of the wiped joint. More lead pipe is being made today than ever before, which goes to show that lead pipe is being used and the only successful way of joining is with the wiped joint. Some plumbers' helpers of

today seem to think that joint wiping is of no account. To a certain extent, I can sympathize with them. Most of these boys are learning a trade in large cities and working for concerns that do nothing but a large contracting business. This large work is carried on differently from the small work. Wrought-iron or steel pipes are used to a great extent in this work and a very small amount of lead is used. Sometimes the job will be completed without the use of lead. The boy who works continually on this kind of work soon comes to think that lead pipes are no longer in use. The writer has found that a boy who has learned to do nothing but screw-pipe work is absolutely lost and cannot perform the duties of a plumber, other than screw-pipe work. It must be borne in mind that lead pipe and cast-iron pipe work are being used today in all parts of the country and in some parts more than in others. Therefore, the boy must grasp all branches of the trade that he has chosen to follow and not be a one-sided man. Joint wiping belongs to the plumber alone. The plumbing trade differs from all other trades in that it has joint wiping for its distinctive feature.

A few attempts at joint wiping will convince the beginner that it is not the easiest thing in the world to learn. Let me caution the beginner not to get discouraged. He must have patience and a firm resolve to master the art of joint wiping and not let it master him and keep him back.

So, as we now start on exercises of joint wiping, let the beginner constantly keep in mind that all boys must become perfectly skilled in the art of joint wiping before they can be considered plumbers. Keep in mind also that the examination that one must take to get a plumber's license contains an actual exercise in joint wiping. The one word of advice is not to get discouraged. Continued practice is the only way to success.

The soldering iron is, or should be, conquered by this time. As joint wiping is the next exercise, I shall go over a few general points that experience has taught me and cannot fail to be of assistance to the beginner if they are heeded. In fact, to become proficient, the beginner should remember all the points suggested under this heading. It is necessary in wiping to have good solder. In the chapter on solder, I have given the correct mixtures and how to recognize the proper mixtures. The place where wiping is to be done should be considered. No draught should be allowed to blow across the work as it tends to chill the solder and pipe. Proper support for the work should be procured. If gasoline is to be used for fuel to heat the solder, make sure that the tank is full before starting, otherwise the fire may go out just when the heat is needed most and the solder in the pot has become too cool to wipe with. Have a catch pan and keep all the solder droppings to put back into the pot, otherwise the solder will pile up and the fingers are likely to be pushed into the pile and badly burned. Hold the ladle about 2 inches above the work, the catch cloth about 1 inches below. Do not drop the solder in the same place. Keep moving the ladle. Do not pour the solder on the pipe in a steady stream, but drop it on. It is not a large amount of solder that is wanted on the joint at first, it is heat that is needed. This can be secured better by dropping the solder on than by pouring a large quantity on the pipe. The edges of the joint cool very quickly; therefore heat the edges well and keep them covered with molten solder until the joint is ready to wipe. When preparing joints for wiping, always do the work thoroughly and fit the pieces together tightly so that no solder can get through.

Points to Remember.

  1. First, good solder.

  2. Second, place of wiping.

  3. Third, support.

  4. Fourth, full tank of gasoline.

  5. Fifth, drip pan.

  6. Sixth, ladle 2 inches above the work.

  7. Seventh, cloth 1 inches below the work.

  8. Eighth, move the ladle continually.

  9. Ninth, drop the solder.

  10. Tenth, heat, not solder wanted at first.

  11. Eleventh, heat the edges.

  12. Twelfth, careful preparation.

  13. Thirteenth, clean grease from the pipe.

  14. Fourteenth, cut clean straight edges on paper.


Preparation.—Take 12 inches of 1⁄2-inch strong lead pipe and square off the ends with a rasp. Take the shave hook and scrape the center of the pipe perfectly bright; a space 3 inches each side of the center is correct. The size of the joint when completed should be 21⁄2 inches long. If we should undertake to wipe the joint with the pipe in the present condition, the solder would adhere to all the pipe that was shaved bright. Therefore, we take a piece of paper sufficient to encircle the pipe twice and after putting paste on one side of the paper wrap it around the pipe so that the edge that is cut straight and even is 11⁄4 inches from the center of the pipe. Another piece of paper is pasted on the other side of the center leaving a clean, bright space of 21⁄2 inches. All the pipe should be covered with paper except the 21⁄2 inches in the center.

Fig. 23. Fig. 23.

To Put the Pipe in Position for Wiping.—The most practical way is to take two common red bricks with the 2 by 8 face down and place them 9 inches apart. Lay the pipe on the bricks and place a weight on each end. The solder will drop on to the bench, so it is best to place a piece of paper or a pan of black iron under the pipe to catch the solder that drops. The pan or paper can then be taken up and the solder put back into the pot without waste. A cast-iron pot holding 15 pounds of solder is then placed on the furnace. When the solder has melted and has reached 500° it is ready for use. This can best be determined by putting a piece of paper in the solder. If the paper scorches, the solder is at the right heat; if the paper catches fire, it is too hot.

Now take a 3-inch ladle and heat it over the fire and then dip it into the solder and skim off any dross that may have collected.

Wiping.—With the ladle full of solder in the right hand and the large cloth or the catch cloth in the left hand, begin to drop the solder on the joint. The cloth should catch all the solder as it falls off the pipe. If hot solder is held against the bottom of the pipe, it is heated to the proper heat. Always begin to drop the solder on the paper edges, then drop the solder on the joint itself. Bear in mind that the solder should not be poured on, but dropped on slowly. After the first few drops do not drop the solder directly on to the lead pipe but on to the solder previously put on the pipe. This will save the pipe from burning through. The pipe must be the same heat as the solder before the proper heat is obtained for good wiping. The beginner should practice dropping the solder on the joint, catching the solder and working it around the pipe. By doing this, one becomes familiar with the feeling of hot solder, which is the secret of successful wiping. When the solder works easily around the pipe, drop the ladle and take the smaller wiping cloth in the right hand and with both cloths draw all the solder on top of the pipe. With fingers on the corners of both cloths, clean off the left-hand edge and with the right hand draw the surplus solder across to the right-hand edge. Next, clean the right-hand edge of the joint pushing the surplus solder onto the cloth in the right hand. Work this solder on to the bottom of the joint. Now discard the catch cloth. Holding the wiping cloth with the index fingers on lower opposite corners, shape the under and front side of the joint. With the middle fingers on opposite lower corners of the cloth shape the back and top. Keep the index and middle fingers on the edge of the cloth and the edge of the cloth on the edge of the joint. This position together with the size and shape of the cloth will give the joint the desired form and appearance. Particular attention is called to the position of the fingers as shown in the figure.

The last wipe should be a quick stroke coming off of joint on a tangent. If the solder is at right heat, the cloth will not leave a noticeable mark. If, however, the solder is too cold, a ragged edge will result. Sometimes a cross wipe is made for the last stroke and a good finish obtained.

Points to Remember.

  1. First, width of the joint, 21⁄2 inches.

  2. Second, allow no soil or paste to get on the joint.

  3. Third, a 3-inch ladle should be used.

  4. Fourth, 500° is the working heat of solder.

  5. Fifth, paper test for solder heat.

  6. Sixth, position of wiping cloths.

  7. Seventh, do not drop solder on the lead pipe.

  8. Eighth, hold the ladle 2 inches above the pipe.

  9. Ninth, wipe the edges of the joint first.

  10. Tenth, wipe and shape the joint quickly.

The above procedure of wiping will be found to work out very easily if followed closely. Do not pour the hot solder onto the cloth as the cloth will burn through and soon be useless. A little more oil should be put on the cloth after using it for awhile. The cloth should be turned around and the opposite side also used. The cloth will last considerably longer if sides are changed frequently. The solder should not accumulate on the pan, but should be continually put back into the pot. The "metal," as solder is sometimes called, should never be allowed to become red hot.

The above method of preparing pipe is suggested for beginners only and will be found to be a great help to them. In actual practice the joint must be prepared differently. The method used in trade is as follows:

The joint is used to join two pieces of lead pipe. Take two pieces and rasp the four ends square. With the tap borer clean out the end of one pipe a trifle, then with the turn pin enlarge this end just a little as shown in the figure. Then rasp the edge off about 1⁄8 inch as shown. Take the other piece of pipe and rasp one end as was done in the cup joint, making it fit into the first piece. Then place the two ends together and with the bending iron beat the pipe, making the joint as tight as possible.


The next position in which the beginner is to wipe a joint is on an angle of 45° to the right.

Preparation.—To prepare this joint, proceed as in the horizontal round joint. I will enumerate a few of these points. A piece 12 inches long of 1⁄2-inch pipe is cut off and the ends squared. A strip in the center, 6 inches long, is shaved clean. Paper and paste are put over the pipe except 21⁄2 inches in the center. Grease can be put on the pipe in between the pieces of paper and will keep the lead from oxidizing.

Placing Pipe in Position.—There is no need of an elaborate system of holding the pipe in position. Take a red brick and place the 4 by 8 face down. This will do for the bottom pipe. For the top of pipe to rest on, place two bricks one above the other; this will give the correct position. Place the pipe on the brick and with a ladle full of half molten solder pour a clamp of solder over the end of the pipe. This will hold the pipe firm for wiping. Place a catch pan under the joint for solder to fall in.

Wiping.—The method of wiping this joint is practically the same as wiping the horizontal joint. The catch cloth should be held parallel with the bench tilting a little from front toward the back. The ladle is held the same and solder is dropped on as before. The ladle should be continually moving while dropping solder, not allowing the solder to drop twice in the same place. When the solder has been worked around the pipe and is at working heat, the solder is drawn up with both cloths and the top edge wiped first, then the bottom edge; the surplus solder is put on the underside of the joint, and then with three or four wipes the joint is made symmetrical and finished.

Things to Remember.

  1. First, prepare like the horizontal joint.

  2. Second, use brick to place in position.

  3. Third, hold tools as in horizontal joint.

  4. Fourth, top edge cools first, therefore, wipe it first.

  5. Fifth, hold the wiping cloth at an angle of 45° when wiping, with fingers placed as noted in previous joint.

  6. Sixth, make solder clamp for holding the pipe.


When the preceding joint is well mastered and a number of good joints have been wiped, turn the pipe on an angle of 45° to the left.

Preparation.—The preparation for this joint is exactly the same as for the horizontal joint. The beginner should turn back and read carefully concerning the perfection of the joint. Bear in mind that the pipe must be correctly prepared or a good joint cannot be made. The edge of the paper must be cut not torn.

Placing Pipe in Position.—This pipe can be placed in position the same as the preceding one. If heavy weights are placed on the ends of the pipe, a bad habit may be formed by the one learning to wipe. That is, the habit of pressing hard on the joint when wiping. In the preceding joint, if the beginner presses too hard, the pipe will fall off the bricks.

Wiping.—Proceed as described for previous joints. The top edge must be favored a little. The hot solder will run down to the bottom edge; therefore less solder should be dropped on it than on the top edge. When the solder is at the proper heat for wiping it requires only a light touch to wipe the joint. If it appears necessary to press hard on the joint to wipe off surplus solder, it shows that the solder is not at the correct wiping heat.


Preparation.—This joint can be prepared exactly like the preceding one. In fact, the same piece of pipe can be used throughout. When preparing this joint the end that is to be on the bottom should be well covered with paper.

Placing in Position.—The best way to hold this joint in position for wiping is to stand the pipe upright on one end with the pan underneath. A piece of furring strip should be run from the top of the pipe to the wall. Secure the strip to the wall and drive a nail through the strip into the bore of the pipe. Place a weight on top of the strip and the pipe is ready.

Wiping.—The procedure of wiping this joint is entirely different from that in the other positions. The solder is thrown onto the joint from the ladle. The catch cloth is held up to the pipe and as much solder as possible is held on to the pipe. Move the ladle around the joint, throwing a little solder on as the ladle is moved. Notice now that all the solder runs to the bottom edge, leaving the top edge cold. The solder that accumulates on the bottom edge should be drawn up to the top edge with the cloth. Then splash more solder on to the top edge and as the solder runs down the pipe catch it with the cloth and draw it up again. The solder can be worked around and up and down the joint, but always keep the top edge covered with hot solder. The solder is likely to drop off the joint entirely unless watched closely. When the correct heat is obtained, drop the ladle. Take the wiping cloth in the right hand and with the fingers spread, clean off the top edge quickly, then shape the joint with the one cloth. With a little practice you will gain this knack. The joint can then be wiped. The left hand can steady the pipe. Spread the index finger and third finger to opposite sides of the cloth and wipe around the joint.