Note: The acetylene is used at a pressure of about 3 lbs. per sq. in. The cost of oxygen is estimated at 3 cents, and of acetylene at 1 cent per cubic foot. Labor is estimated at 30 cents per hour.

Welding axles, from..............$2.00 to $5.00

Cracked cylinder water Jackets .... 8.00 to 12.00

Broken cylinder lug welded on___ 2.00 to 4.00

Cylinders cracked inside.......... 12.00 to 20.00

Broken crank case, aluminum..... 5.00 to 20.00

Main side frames broken, each..... 15.00 to 25.00

Defects, known as "cold shuts", frequently develop in steel forgings and the average cost of welding these is from 50 cents to $2.00 each. Engine connecting rods have been welded at $3.00 to $12.00 each, depending upon the size. Stern posts of vessels frequently break during storms and these can be welded for $35.00 on small ones up to several hundred dollars for large ones. Blow holes in iron castings cost 25 to 75 cents to fill in.

The following figures on various repair jobs have been compiled by the Oxweld Acetylene Company, Chicago, and cover a wide variety of work:

Welding stern post of lake steamer "Mullen"............$32.00

General repairs on Cahall water tube boiler.............. 29.49

Small cast-iron gas engine frame, sand spot in one side......40

Broken locomotive side rod, steel forging................. 5.22

Short crack in locomotive side sheet, 4 inches long........ 2.50

Cracked locomotive mud ring, nine hours................ 22.00

Small patch in side sheet of locomotive fire box........... 10.01

Medium sized patch in side sheet of fire box.............. 17.38

Three short cracks in fire box sheets, 11 inches total....... 3.46

Small repairs to steel railway motor case................. 8.82

Welding lugs on small shaper arm, steel casting........... 4 50

12-inch crack in end of pressed steel car bolster........... 6.16

Crack in cast-steel truck side frame, "Andrews" truck.....85

Welding small lug to cast-iron cylinder head.............. 5.89

Patch on side of aluminum crank case for automobile engine 1.50 Cutting risers from large steel castings, per sq. in...........014

In conclusion, the student is urged to familiarize himself with the rules laid down by the National Board of Fire Underwriters concerning the installation, care, and operation of oxy-acetylene and other types of hot-flame welding apparatus. The complete rules are too lengthy for reproduction here, but a copy can be obtained from the headquarters of the Board in Chicago and will be interesting reading.