T"i 



THE 

 ter 



Popular Science Monthly 



An All -Steel Screwdriver 

 IE scre\vtlri\ (.T to be (lescribfd 

 is constructed entirely of steel 

 and while feeling heavy at first will be 

 found to be very well balanced and able 

 to stand hard usage. If the blade is 

 broken it can be easily repaired or re- 

 placed or different sized blades may be 

 used. 



The whole tool, including the fluting 

 of the handle, was made on a small 

 back-geared lathe with a hand-fed car- 

 riage. 



A 5" length of i>^" cold-rolled steel 

 shaft was cut off and a 3/8" hole 3" deep 

 bored in the center of it to take the 

 blade. The handle was then roughed 

 out nearly to the finished dimensions 

 and a light finishing cut taken all o\er 

 it at high speed. 



The handle was fluted as follows: 

 The circumference of the large end was 



1^21 



A Buck-Saw Attachment 

 i ordinary' i)uck-sa\v trainc has a 

 tendency to cramp the upper 



hand when sawing. To 



eliminate this, bore a K 

 in. hole through the top 

 part of the frame just 



_ fan/ J fee/ 



fi Croore^ 

 A screwdriver made entirely of steel 



divided and punch-marked into twelve 

 equal parts. Then a hole was drilled 

 and tapped for a la," set-screw in the 

 small part of the handle, as shown in 

 the drawing, and a length of 3/8" rod 

 set in and countersunk for the set-screw. 

 The outside end of this rod was held 

 in the lathe-chuck, the large end of the 

 handle being held in the back-center. A 

 steel lathe-tool with a small rounded 

 end, was placed in the tool-post turned 

 over on its side; the lathe-chuck was 

 kept from turning by locking the back- 

 gears, and then each groove was cut by 

 moving the carriage along by hand and 

 taking a succession of light cuts until 

 the groove was of the required depth. 



The blade was made of a piece of ^'g" 

 tool steel with the tip end hardened and 

 was held in the handle by means of the 

 y^" set-screw, countersunk about J^". 

 A set of blades could be made of differ- 

 ent lengths or with tips of different 

 widths. 



A simple peg makes the task of sawing 

 wood a little less strenuous 



below the tightening wire. Cut off a 

 piece of an old broom handle 4 ins. long 

 and drive it through this hole half pro- 

 jecting on each side. By gripping this 

 pin with two fingers on one side and two 

 other fingers on the other side, with the 

 saw frame between, the wrist will not 

 be twisted. — W. J. Albin. 



How to Etch Glass 



W.^RIM a piece 

 of glass care- 

 fully; if heated too 

 rapidly the glass 

 will crack. Rub 

 paraffin or beeswax 

 over the warm sur- 

 face of the glass. 

 With a blunt in- 

 strument print the 

 desired wording. To some fluorspar 

 (calcium fluoride) placet! in a metal ilish, 

 add enough concentrated sulphuric acid 

 to moisten the powder. Place the glass, 

 with the marked side down, over the 

 metal dish containing the above chem- 

 icals and leave it over night. In the 

 morning, scrape the paraffin off and the 

 desired words will be etched on the glass. 



The fluoride bath 



