Page:Popular Science Monthly Volume 88.djvu/636

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��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-

��2

�Wood

�strips 24'' X

�6" X

�1"

�2

� �" 24" X

�4" X

�1"

�4

� �9" X

�6" X

�1"

�1

� �strip 31" X

�4" X

�1"

�1

� �9" X

�9" X

�1"

�1

� �" 12" X

�9" X

�1"

�2

�length

�s of iron rod

�%" X

�12"

�1

�heavy

�barn-door hinge.

� �1

�holt 2 X % with

�a thumbscrew

�tap.

� � � � ��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.

�� �