Popular Science Monthly 



293 



celluloid should be placed between them 

 and the end papers to keep the leaves 

 from absorbing moisture and becoming 

 wrinkled. 



The easiest way to letter the cover 

 of the book is to make a stencil of the 

 paper cover of the magazine, as this 

 will save the labor of laying out the let- 

 ters. Lay the cover paper upon a hot 

 plate and saturate it with paraffine wax. 

 Wipe off the surplus wax while it is 

 still hot. Lay the waxed paper upon a 

 piece of straw board and cut the letters 

 out, stencil fashion, using the sharp 

 blade of a penknife. Use a good water- 

 proof India ink and a stiff brush from 

 which surplus ink has been removed. 

 Draw the brush inward from the edges 

 of the cut out letters. The letters may 

 be finished by filling in the blank spaces 

 with a pen. 



A Self-Adjusting Sandpaper Block 



A SANDPAPERING block that au- 

 tomatically adjusts itself to both 

 convex and concave surfaces of any ra- 

 dius is very easily constructed by using 

 a piece of rubber packing for the face 

 and glueing to the back or fabric side 

 wedge-shaped strips of hard wood of the 

 general dimensions shown in the draw- 

 ing. These strips should be about 1-32 

 inch apart where they fasten to the rub- 

 ber, so that the face will bend easily. 



The sandpaper is folded over the block 

 in the usual way and with very slight 

 pressure the face will conform to the 

 surface to which it is applied. 



This sandpapering 

 block adjusts it- 

 self to any 

 surface on 

 which 

 it is 

 used 



A 



A Handy Way to Repair a Tire 



VERY convenient instrument 

 which may be used to repair punc- 

 tured tires can be made from a common 

 button hook. Straighten or cut oflf the 

 hook part with a pair of pliers. Saw a slit 

 about Vs inch from the end up the stem 

 of the hook with a hack saw and round 

 ofif the ends into a fairly sharp point. 

 With a knife cut all the sharp edges from 

 the slit so it will not tear the rubber 

 bands. Make a hook as shown in draw- 



With this tool rubber bands can be 



pushed into a puncture, to make an 



excellent quick repair 



ing. and passing the rubber band first 

 through the slit and then over the hook 

 enough times to fill up the hole in the 

 tire, dip the rubl^er and hook in tire ce- 

 ment and push through hole. Unhook the 

 rubber band and draw out the hook care- 

 fully with a twisting motion so as not to 

 remove the rubber band. Cut oflf the pro- 

 truding rubber and you will have your 

 puncture repaired in excellent shape. 



A New^ Use for Broken Drills and 

 End Mills 



BROKEN drills and end mills 

 should not be thrown away, as 

 they will be found useful if a special 

 socket is to be made for the lathe or 

 miller, when a drill or end mill is to 

 be held. 



By grinding the tang off, it can be 

 turned around in the socket to ascer- 

 tain if the taper has a bearing the 

 whole length. If a drill or end mill is 

 used without thus changing it, the 

 tang will prevent its being turned 

 around. 



