8 Laboratory Arts 



wider than the stone is done by rubbing opposite ends of the 

 edge upon the stone on alternate strokes, thus using the whole 

 surface of the stone, and sharpening the whole edge. In the 

 case of a jack plane iron, the edge should have the corners 

 rounded off a little, in order to prevent its leaving marks 

 on the wood, but smoothing plane irons and chisels are 

 sharpened to a "square" edge. The stone having done its 

 work, examination of the edge will disclose a small piece of 

 metal still loosely adhering to the tool, and this, known as the 

 " wire edge," is removed by stropping, either on the palm of 

 the hand or upon a leather strip; the latter is preferable for 

 beginners, but the former gives better and quicker results. 



Setting of Tools. Planes are set by placing the cap 

 iron upon the plane iron, and bringing the two edges close 

 together, the distance separating the two edges depending 

 upon the work to be done. Jack planes usually have the 

 cap iron set back from the cutting edge of the plane iron 

 from ~" to |". Trying planes may have their irons set finer, 

 not exceeding ~" ; and smoothing planes have their irons set 

 very close together, usually not exceeding ~" back. These 

 figures are for fully screwed up irons ; naturally they will be 

 exceeded when the screwing is commenced. 



Having fixed the cap iron, the double iron is placed in 

 the plane mouth, and the wedge inserted, holding the plane 

 in the left hand in such a way that the thumb prevents the 

 wedge advancing too far. The iron is then advanced until 

 up to ~" for a jack plane, and a mere glimmer for a smoothing 

 plane is visible above the base. The wedge is then tightened 

 by a single smart blow of the hammer. If this has advanced 

 the iron too much, it may be withdrawn after a smart blow 

 has been administered either to the top front or the back end 

 of the plane. 



The tool may then be tried upon the wood to be worked, 

 and the iron readjusted if necessary. 



The directions for sharpening plane irons may be con- 

 sidered to apply to most edged tools, save gouges, which are 

 sharpened from either side by a chip of Arkansas stone. 



Saws should only be sharpened by a tool maker. 



