124 



Popular Science Monthly 



A practical home-made gasoline gage for the 

 automobile 



A Gasoline Tank Gage 



AGASOLINE tiink gage may be 

 made as follows: Obtain a brass 

 rod of about 3/16-in. diameter, 2 ins. 

 longer than the tank is deep, a cork 

 about i},4 ins. in diameter and H in- 

 thick; also a strip of copper yi in. wide, 

 about 1/16 in. thick and as long as the 

 tank is deep. To make the holes in the 

 cork-Hoat, obtain an iron rod and a 

 piece of strap-iron of the right size, heat 

 them and press into the cork. Repeat 

 this operation until the holes are burned 

 through the cork. 



Put one end of the copper strip in a 

 vise and with a pair of pliers giv-e it one 

 complete turn. See that the lloat slides 

 freely upon it. Place the float on the 

 bra.ss rod and flatten the ends of the 

 rod for a distance of i in. and drill holes 

 for copper or brass wire to be soldered 

 to each end of the copper spiral for 

 bearings and pointer. Assemble as 

 shown in the illustration. Make a hole 

 in the filler-cap to acconnnodalt- the 

 pointer and solder the upper end of the 

 brass rod to the cap. 



The float should be given two coats 

 of shellac. Make a zero mark on the 

 filler cap where the pointer stands, when 

 the tank is empty. Pour in one gallon 

 of gasoline, put the gage in place and 

 mark a figure 1 whore the pointer stands, 

 and so 011 until the tank has been com- 

 pletely filled. — ^Claude M. Sessions. 



Lapping a Scored Automobile 

 Engine Cylinder 



SOMETIMES an automobile engine 

 cylinder will become scored due to 

 defective cooling or lubrication, or on 

 account of dirt in the oil. This results 

 in loss of power, because the compression 

 in the cylinder is reduced by escaping 

 gas. If the scratches are not too deep, 

 they may be lapped out and the expense 

 of re-boring the cylinder saved. A very 

 simple yet effective lapping-tool is 

 shown. A main spindle of mild steel 

 carries a tapered expander-plug, which 

 fits a corresponding taper in a cast- 

 copper lap. This has four grooves cut 

 in it, two extending from the top 

 nearly to the bottom, two from the 

 bottom nearly to the top. These permit 

 the lap to expand when it is forced down 

 on the expander-plug by the clamp-nut. 

 A driving-pin is inserted in the spindle, 

 this turning the lap because it fits one 

 of the slots. 



The scored cylinder is clamped secure- 

 ly on the bed of a drill-press and the lap 

 inserted in the bore after it has been 

 covered thoroughly with abrasive ma- 

 terial, usually fine emery and oil. The 

 diameter of the lap is slightly less than 



uz::j 



A lapping tool for engine cylinders avoids 

 the necessity of reboring 



