Page:Popular Science Monthly Volume 91.djvu/958

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942 Popular Science Monthly

Protecting Drawings on Front Edge of Drawing Board

WHILE making large drawings it is often necessary to allow the drawing to extend over the front end of the drawing board. To prevent the worker from crush- ing the drawing paper while in this position, simply fasten a thin strip of wood to the front end or edge of the board with a small block under each end. Allow the extending edge to drop behind the strip and it will be well protected. — Thos. W. Benson.

��Setting a Lathe Quickly for Taper Turning

A SHOP recently received an order for turning a large number of tapered brass plugs of varied lengths and diameters. The lathe on which the orders were filled as they came was an old one, not having the common taper attachment, which would have made the job an easy one. The taper per foot in inches was of course given with each lot. The illustration shows the man- ner of setting the tapers, which, though they did not afford the rapidity of an up- to-date machine, gave excellent results. One of the plugs out of each lot was

���Manner of setting the tailstock of a lathe for turning a taper of a given length and size

turned back for about 4 or 5 in. of its length with the centers in line, as shown in Fig. 1, A-B. The tail-stock was then set over to one-half the given taper, and the end tips of a 12-in. box scale brought in contact with the center points. In Fig. 2 a piece of

��steel C squared on three sides was then drawn fairly tight in the tool post and tapped with a hammer to bring it in line with the face of the square head. The tool post was then run back and the work again placed in the machine. A small square was placed against the piece C, and the tail stock again thrown either way until the leg of the square was exactly in line with the turned portion A-B. This afforded the distance D-E, Fig 3. The sizes at the ends could then of course be readily turned. There are other ways to secure tapers by trial cuts which give good results, but owing to the size of the work in this case the method used was the most practical since it gave close and exceptionally accurate re- sults. — F. W. Bentley.

��Making a High Gloss Finish on a Matt Surface Picture

A PHOTOGRAPH submitted for publi- cation was returned to me with a request for a clearer picture. As I no longer had the negative or more prints, I naturally wanted to fix the one returned so that it would pass inspection. It was accomplished in the following manner: I laid the print on a table and rubbed over it five coats of floor wax with a soft rag. Each coat was rubbed down lightly, but thoroughly. The last two coats I finished by rubbing the print upside down on a piece of blotting paper. This resulted in a high gloss print, bringing out the detail in the shadows so that i t was accepted as a new print. — Henry Simon.

��How to Straighten a Warped Drawing Board

IF a drawing board should warp in spite of the wooden battens on the back of it, it may be straightened as follows :

Paste strips of paper on the concave side of the warped board so that the paper strips are at right angles to the hollow. Also paste strips diagonally across these so that the board face is crossed and recrossed by strips of paper. Leave the strips on for a week and then wash off and it will be found that the board has regained its flat surface.

I have seen boards straightened in this way which were so badly warped that the paper pulled hard enough to start the glue holding the inset pieces on the back. The pull of the paper is not noticeable a few days after it is put on.

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