Show ali HOMEMADE DRAFT GAUGE how one can be aas ly made in the home work shop screw two pieces of I 1 inch pipe about eight inches long into a 1 inch return bend and put a reducer on the top end of each pipe reducing it to inch remove the plunger from a small bicycle pump and solder a piece of copper on the top of the pump making it airtight this Is to be used for a float as it drops down aa one of the 1 inch pipes olcen hemore the pressure spring from a small steam gauge and attach the gauge to one end of the pipe as shown in the illustration solder a fine stiff brass wire to the center of the float letting the wire extend up through the reducer to which the gauge la screwed and connect the upper end ot the wire to the bottom corner of the triangular ratchet of the gauge pill the with machine oil until the float raises enough to turn the hand back to zero says the engineer s he view screw a piece of inca pip in me other reducer and run to the side ot the smoke box As the draft tends to create a vacuum the oil in the inch pipe raises on the side connected V tube nd gauge to the smoke flue and lowers on the gauge side this crises the float to drop thus pulling down on the ratchet and turns the hand upward oil Is a good liquid to use as it neither freezes nor evaporates |