For Practical Workers 



A Spirit-Level for Use in Dark Places 



AMILLW'RICiPiT must often set 

 up machinery and benches before 

 a tenant has moved into a building. As 

 the gas and electric lights are not 

 turned on before the tenant takes pos- 

 session, it is hard to level shafting, 

 foundations, benches, etc.. in dark 



PU5M auTTOn ■■ 

 POCKET fQt^ LIGHT ON 



FLASHLIGHT HORIZONTAL LLVEL, 

 BATTERY ust WHEN NEEDED 



A spirit level equipped with a small flash- 

 light will be found very useful for use in 

 dark buildings 



places, especially on dark, rainy days. 

 Candles are often employed, but both 

 hands are required. W ith the level to 

 l;e described, one hand is always free. 



Use a small, round flashlight battery 

 and drill a hole in one end of the level, 

 large enough to hold it. With a ruler 

 as a guide, make grooves with a thick- 

 set i)enknife on the outside of the level 

 to hold a fine wire. Push the wire in 

 with a screwdriver, fill in the top with 

 rosin or wax and finish smooth. Drill 

 holes under each level, just deep enough 

 to hold a flashlight bulb. Solder wires 

 on them, and fill in with rosin or wax 

 and finish smooth. The rosin or wax 

 fdling will hold the wires and bulb se- 

 curely. 



Drill holes for the smallest size but- 

 tons obtainal)le, and push the buttons in 



with a block of wood. A three-wire 

 system is employed. The buttons are so 

 located that the hand which places the 

 level, lights the level with the thumb of 

 that hand, thus leaving the other hand 

 free to work with. A sliding cover is 

 put on the end and screwed in to keep 

 the battery in position. — T. F. BusCH. 



To Face Left-Hand Nuts 



IN facing left-hand nuts, damage is 

 often done to the facing tool or nut 

 arbor, by the nut's starting to unscrew, 

 and pushing the tool to one side or 

 breaking it. The nut arbor or mandrel 

 shown, will prevent the nut from com- 

 ing loose, holding the nut in place until 

 one side has been faced. It consists of 

 the threaded piece A on which the arm 

 B is held by the set screw. When the 

 nut has been screwed up tight, the shaft 

 arm B is set so that the cap screw C can 

 be tightened up against one of the fiat 

 sides of the nut. The set screw should 

 have a copper end if it is used on nuts 

 that have had their sides finished. When 

 many nuts are to be faced, it will pay to 

 make a small cam that pivots on the end 

 of the arm B to take the place of the 

 screw C. The arbor can be held between 

 lathe-centers or made to fit the mandrel 

 of anv lathe. — C. Anderson. 



This nut arbor or mandrel holds the 

 nut in place until one side has been faced 



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