What is solder?

Solder may be called a cement, and is used for joining various metals together, such as tin, copper, lead, etc.

Of what is solder, used by plumbers, composed?

It is composed of lead and tin in different proportions, according to the purpose for which it is used.

Give the proportions of different solders used in plumbing work.

Wiping solder, 3 parts lead, 2 parts tin.

Bright solder, 1 part lead, 1part tin.

Are the above proportions definite in the case of wiping solder?

No, each plumber will temper his solder to suit himself - some working it finer than others.

What is a good test for wiping solder?

A good test in general is to pour a little of the melted solder upon a cold surface. If it cools, leaving a mottled appearance, it is about right, if it leaves a granulated appearance, it is too coarse, or if a very bright appearance, too fine.

Give the melting points of the two solders named above.

Wiping solder melts at about 450 degrees; bright solder at 375 degrees.

What are the melting points of lead and tin?

Lead melts at 612 degrees; tin melts at 442 degrees.

Why does overheating spoil wiping solder?

It burns out the tin, since tin is consumed at a lower temperature than lead. This makes the solder too coarse.

When solder sticks to the wiping cloth, what does it show?

It shows that there is too much tin in the solder.

What is the result if solder contains too much lead?

The solder will be coarse, and the joints liable to be porous.

What is the result if the solder contains too much tin?

The solder will be too fine, will stick to the wiping cloth, and will run off from the underside of the joint, making a good joint a difficult matter.

When the cloth scratches in wiping, what should be done?

Rub into the cloth a little powdered chalk.

How should a joint be treated after it has been wiped, to give it a mottled appearance?

While it is cooling, blow upon it. Many spit upon it while they are blowing, with a sort of spray.

What is the proper width of a 4-inch joint?

About 1 1/2 inches.

In case of a rough place on a joint so situated that it cannot be rewiped, how can it be smoothed up?

With a hand torch, it can be softened, and the imperfect part be wiped over.

How should a bursted lead pipe be wiped?

With a soft dresser, carefully beat back the extended pipe, until it has been reduced to its original shape, and the burst is entirely closed. Then properly soil and scrape as large a surface as the joint is to cover, being careful to extend it where the pipe has not been strained enough to injure it. After greasing, a good joint can then be wiped, in the shape of a patch, which will make the pipe at this place stronger than ever.

What substances make wiping solder worthless?

Zinc particularly, and antimony also.