608 



Popular Science Monthlj 



A Handy Drawing Table 



A DRAWING table, which can be 

 adjusted for height and angle, 

 will amply repay its builder in con- 

 venience for the time and pains spent 

 in its construction. The materials are 

 reasonable in cost. 



After the stand is constructed, any 

 drawing board may be attached to the 

 upper part, and the screw-heads should 

 be countersunk. 



A complete list of the materials re- 



A drawing table which can be]made by an amateur, 

 grams show the structural details 



quired is as follows 



makes a fine line; a flat point makes a 

 wider line. Write or mark through 

 wax, so that the writing tool touches 

 the steel; blow off crumbs of wax and 

 apply the acid. 



Fonnula — Etching Acid 



Muriatic Acid i part 



Nitric Acid i part 



A\'ater i part 



Mix in bottle, using a glass stopper as 

 other corks do not last. 



Apply acid jvith a fountain pen filler 

 very slowly. Etching 

 should continue until 

 the acid turns a rusty 

 color. Then wash off 

 the tool in water, heat 

 it and wipe off the 

 melted wax with a 

 cloth. Polish the 

 tool. Oil it to prevent 

 reaction of water to 

 rust. Do not put the 

 used acid back in the 

 bottle, or allow the 

 smallest drop of acid 

 to touch any uncover- 

 ed part of the tool, as 

 it will eat a hole in it. 

 All this takes about 

 To retard the action of the 



The dia- 



five minutes, 

 acid in etching, add another part of 

 water. This is only done when a num- 

 ber of tools are to be etched. 



It is best to wax all at one time, writ- 

 ing on all, and leaving the etching as a 

 last operation. Do not leave the bottle 

 containing the acid near any tools. The 

 fumes will rust them. 



1 bolt 5" X %" with two 1" washers 

 and two thumbscrews. 



1 pin (a cheap screwdriver with the 

 flat part filed off will do). 



Acid Engraving in Steel in Your 

 Own Handwriting 



TAKE the tool to be marked, and 

 heat it until it melts wax. Rub 

 and melt wax over the area which 

 is to be etched and harden the wax 

 by cooling. Do not heat the wax and 

 rub on a cold tool, as it hardens too 

 quickly and does not hold, when writing 

 on it. Use a pointed file or scratch-awl 

 to mark or write with. A fine point 



Lighting a pipe in the wind is difficult 

 because it is hard to keep the match burn- 

 ing until it reaches the pipe. Scratch the 

 match on the pipe, and all such troubles 

 will be avoided 



Lighting Your Pipe in the Wind 



A MATCH - SCRATCHER, easily 

 shielded from the wind by the 

 hand, is formed by making grooves on 

 the side of one's pipe with a three- 

 cornered file as shown in the illustra- 

 tion. — ^Thomas Sheehan. 



