The other knife or spatula in general use is made from thin steel and generally of such quality that the heating of the lamp will take out the temper so that the knife is no longer flexible.
Alcohol lamps and torches are obtainable in various styles and materials. A brass lamp is the safest to use in a complaint kit, although glass will suffice. These lamps vary from two ounces to eight ounces, and have a round wick which can be covered by an air-tight stopper, to prevent the evaporation of the alcohol.
See Plate Xa, page 387, for illustration of the electric burning-in knife which may be attached to any light socket. A transformer can also be had to reduce 220 volt current to 110, the voltage required.
A steel scraper is used for shaving down the wood cement after burning-in. The scraper is a straight piece of tool steel, about six inches long, cut off square at the ends. The sharpening is done by grinding the ends smooth and merely grinding the sides to take off the roughness. It is not sharpened like the bevel edge of a plane knife. It is merely smoothed off so that when the square edge is passed over the cement it will shave off a portion of the cement without cutting into the surface, as would be the case if the edge was sharpened like a knife. An ordinary scraper would suffice, but it is too wide for leveling cement. The scraper should not be over one and one-half inches wide and about one-sixteenth inch thick.
FELTS FOR SANDING OR RUBBING
Several pieces of felt, woven and pressed, should be carried in the kit. One piece, about one inch thick and twice as wide, and about four inches long, suffices for a sanding block and rubbing with pumice on all flat surfaces. Another piece of one quarterinch material and about 3x5 inches in dimensions must be in the kit for rubbing all rounding surfaces, etc. The cork block referred to in wood finishing for sanding is useful.
BRUSHES FOR PATCHINGM
The illustrations following show the brushes that can be actually employed in patching and finishing of patched surfaces. Plate V is a robbing brush for dolling inaccessible surfaces; some of them are reversible so that one end will not out-wear the other.