Page 665 the smooth sheet 725 



725. Selection of Pen Points 



The drafting pens on the General Schedule of Supphes are not uniform in quahty 

 nor are they tested as thoroughly as the pencils are. As in the case with pencils, an 

 experienced draftsman will know with which make and type of pen he can obtain the 

 best results for a particular style of drafting. 



The Gillott crow-quill pen (No. 659) is believed to be the best all-purpose pen 

 for fine work, especially after the point has been dressed slightly. For a draftsman 

 who prefers a fine limber jDoint, Gillott No. 290 or No. 291 is perhaps the best. For 

 average work Gillott No. 170, and for heavy work such as shoreline Gillott No. 303 

 or No. 404, are recommended. For the very fine lines required in inking day letters 

 and position numbers on sounding lines, a Hunt No. 104 may be preferred to the 

 Gillott No. 290 or the crow-quill. 



In 1943, because of the war, Gillott pens were not obtainable. Esterbrook pens are 

 the best available on the General Schedule of Supplies. The numbers of comparable 

 grades of Esterbrook pens are 62, 354, 355, 356, 357, and 358, for Gillott pen numbers 

 659, 291, 290, 170, 303. and 404, respectively. 



726. Inks 



Waterproof drawing inks, particularly colored inks, vary considerably in quality 

 from year to year and no recommendations can be made at any particular time with 

 the expectation that they will be found correct in the future. The inks listed in the 

 General Schedule of Supplies are satisfactorily tested before listing, and it is believed 

 that at any given date the General Schedule is, perhaps, the best guide. It does not 

 follow, however, that if ink of one make is satisfactory in one or two colors, other colors 

 of the same make will necessarily be satisfactory. Experience is, after all, the best 

 guide. 



Black waterproof drawing ink is the only ink which is entirely waterproof. Other 

 colored waterproof inks are not fully waterproof and this fact should be carefully 

 considered in connection with their use. 



In the past, Higgins waterproof drawing ink has, perhaps, been found consistently 

 better than other makes. At the present time both Higgins and Keuffel & Esser black 

 waterproof ink comply with the federal specifications. 



7261. Celluloid Ink 



While ordinary drawing ink can be used on celluloid sheeting, it is preferable to 

 use celluloid ink because it makes a more permanent bond and does not rub off or chip 

 so easily. It can be removed with a steel eraser; light ink work can be removed with 

 an ink eraser or an erasing machine, the latter leaving a better surface for redrafting. 



Celluloid ink will be furnished by the Office on request. It is available in light, 

 medium, and heavy grades. The medium is more generally used. The solvent in 

 celluloid ink evaporates rapidly making it necessary to thin the ink from time to time. 

 This is done with a special thinner, which is also available on request. A small quantity 

 at a time should be thinned, suitable for the individual draftsman. 



727." Erasing and Cleaning 



During the construction and plotting of the smooth sheet every effort should be 

 made to keep the sheet clean and to avoid placing unnecessary marks thereon (see 731). 

 Even with considerable care, a smooth sheet will eventually become slightly soiled. 



465382—44 44 



