An overheated cast-iron steam boiler, with low water level, is very easily cracked when cold water is let in suddenly. The leak caused thereby will sometimes put out the fire and render the boiler useless.

The leak is very easily mended in the following manner: First cool off the boiler by putting on some fresh coal, and leaving the fire door open until the steam pressure has gone down. Then unscrew the safety valve or any other fitting on top of the boiler. Through the opening4 pour in about half a package of ordinary oatmeal. Bran will also serve the purpose.

Then replace the safety valve, and open the feed-water cock, and fill up the boiler with water above the crack. This will stir up the oatmeal. As the water runs out through the crack, it carries particles of the oatmeal with it, which will lodge in the crack and soon stop the leak.

Now close the feed door, and draw up the fire, and the steam generated will force these particles of oatmeal through the crack, which soon will rust and bake there, making' it nearly as hard as the cast iron itself, and it will withstand almost any steam pressure. In fact, it would be impossible for the steam to blow-it out; it simply gels tighter and tighter, making the boiler nearly as good as before. The writer has known boilers mended in this way to last several years.

When the boiler has thus been mended, open partly the feed-water cock, thereby filling up the boiler with water. At the same time draw off the water from the boiler through the drain cock until all the surplus oatmeal is drawn off and the water becomes clear, maintaining at all times the normal water level.

If the surplus oatmeal is not drawn off. it will cause the boiler to foam and blow off through the safety valve, raising more or less disturbance for a long time to come.

Mending Cast-Iron Boilers, Radiators, And The Like

The writer has seen people try to solder up a leak in a cast-iron radiator; but as a rule, after a short time, the fault needs mending again. A much better way is to plug the leak with copper. The accompanying drawings show how easily this is done, making a permanent job. When the radiator is cold, drill a small hole, say 1/8 inch diameter, with an ordinary drill; then witli another drill, preferably flat, ground a little out of center, drill into the same hole a little deeper. It will be seen that the last drill has made the hole somewhat larger at the bottom. Care should be taken not to drill in too deep or through, as there will be nothing to rivet against.

Fig. 283 - Plugging a hole with copper wire.

Fig. 284 - Stopping up a crack with copper plugs.

Now take a piece of copper wire, anneal it, and file or point the end that goes into the hole, so that it will fit the bottom of the same. Cut it off about 3/16 inch longer than the depth of the hole. Then with a small hammer drive it into the hole, and keep on hammering with quick blows until the whole length is driven in and riveted on the outside. The soft copper wire will then fill the enlarged hole at the bottom, and form a head inside the cast-iron.

As the radiator gets hot, the copper will expand and make the hole absolutely steam-tight. If a crack is to be fixed, then a number of holes are drilled at a distance apart that equals nearly the diameter of the copper wire to be used. Then these holes are plugged, and another set of holes are drilled between the first ones, cutting all the cast iron away and part of the copper plugs as well. Then these holes are plugged as before de-scribed. It will now be seen that practically a strip of copper is dovetailed into the cast iron, which will not work loose or come out, and when hot will expand and withstand almost any steam pressure. This operation can also be used in riveting one or more pieces of metal together, especially where a blind rivet is desired. Instead of copper, soft iron or steel may be used, as the rivets need not be steam-tight.