with long iron rods, thus allowing the molten steel to escape into the mold. The platform had been well sprinkled with sand and there was no danger from fire. The stray pieces of aluminum oxide slag were quickly covered with sand and rendered harmless.

The weld was allowed to anneal itself by cooling slowly, the mold box not being dismantled until the following day. When the molding material was finally cleared away, the risers and gates cut off with an oxyacetylene torch and the weld examined by chipping off pieces of metal, the thermit steel was

found to be of fine quality and appearance. The weld was then accepted by the navy yard representatives as being entirely satisfactory.

The total number of 14 working days taken to complete the job does not by any means represent the average time

consumed for making sternpost welds. The other repairs on the NORTHERN PACIFIC detained her for almost four months confinement in drydock. There was, therefore, no hurry on the sternpost weld. Furthermore, this repair required extra time for erecting the high scaffolding and platform, and on account of the delay occasioned in preparing the interior of the casting. Nevertheless, had the sternpost job required more of

a rush the total time consumed on the repair could doubtless have been cut in half.

Interesting as this repair is as a record weld in the marine field, its real interest lies in the fact that as a welding operation it is of no greater magnitude than hundreds of welds which are

being made almost every day. In steel works welds of much greater size are of common occurrence. This repair did not break the world's record through any "daredeviltry" on the part of the repairer in accepting the job, but merely because no marine repair of this magnitude had previously presented itself. Much larger repairs can be completed in absolute safety whenever the opportunity occurs.

Progress in the Application of

Electric Arc Welding

By ROBERT E. KINKEAD, Cleveland

The applications of electric arc and oxy-acetylene welding have been greatly advanced as a result of the conditions brought about by the war. Conditions which produce defective castings have always existed in all foundries, but the labor situation during the period of the war brought about a state of affairs which resulted in a much larger percentage of defective castings than had ever been produced before.

The demand for skilled craftsmen in the foundry industry far exceeded the supply, and the net result was that skilled workmen were spread rather thinly through the industry. While the introduction of molding machines has to a certain extent made it possible for unskilled labor to produce a comparatively high percentage of sound castings, the application of this labor-saving device has not yet become so general, but that there are still a large number of castings which must be made in a manner which requires a high degree of craftsman's skill.

The net result of these conditions during the war was that an alarmingly large percentage of castings came from the sand that were partially or totally defective. This has led to an increased interest in and extended application of welding processes to save these castings.

In the eyes of the highly skilled craftsman, the application of welding processes to correct defects produced in the castings by poor workmanship is nothing short of sinful. However, from the point of view of the economist, welding offers a means of eliminating a large economic waste.

A casting is made to perform a certain service, and so long as it is capable of performing that service satisfactorily the methods used in its production are of secondary importance.

There is no escape from the economic pressure tending to compel the foundryman to reduce the cost of production of his castings. While there are many methods of reducing the cost of production of castings, the salvage of defectives offers some of the greatest possibilities.

In Steel Foundries

The electric arc-welding process has been used in steel foundries for about 10 years, and during that period the sentiment toward salvaging defective castings has changed in a most remarkable manner. This practice is now followed by practically every steel foundry in existence, and there is no question but that if the practice were eliminated completely today the price of steel castings would have to be substantially increased to cover the loss of labor and material resulting from rejection of defective castings. The salvaging of defective steel castings may now be said to be standard foundry practice.

The carbon electrode welding process offers one of the most important means of correcting defects in steel castings. Where this process can be used, in the opinion of the writer the work may be done cheaper and better than by any other means. However, the extensive use of the correction process has developed fields which cannot be covered by the carbon arc process. The metal electrode method of electric welding has been substituted with great success.

The field in which the metal electrode process is best applied is in dealing with small steel castings where the defect is of minor importance and in larger castings where the defect occurs in a section which is thin, and on which the heat must be extremely localized.

Good foundry practice indicates that steel castings which have been welded by the carbon electrode process should subsequently be annealed to relieve any local internal strains which may have been introduced by the application of the heat of the arc. There are occasions, however, when it is extremely inconvenient and expensive to reanneal a casting which shows a slight defect. On such occasions the application of the metal electrode process, owing to the very great localization of the