534 



THE INDIA RUBBER WORLD 



[July 1, 1914. 



Figures 3 and 4 give a detailed view of the turning of the cap 

 and of the barrel of the pen. 



TCUMNG THE RUBBER CAP AND BARREL. 

 The rubber cap. shown at A in Figure 1, is made from a cup, 

 and for the rough-turning operation is placed on an arbor B as 

 shown in Figure 3. The turning is accoinpHshed witli a flat 

 hand tool C. the operator holding it in one hand, guiding it with 

 the thunil) of the other hand. The tool is held on a rest D, the 



by the way, on which the various parts of the pen are turned, 

 are rotated at about 2.000 revolutions per minute. 



The spoon feed, which is marked D in Figure 1, conveys the 

 ink from the barrel to the pen point. This is also made of solid 

 rubber. This is a most important part of the pen and requires 

 extremely accurate and careful work, for the feed pockets, the 

 air vent and the ink fissure ducts must all be cut in their proper 

 places with absolute accuracy. 





Fig. 3. RofGii-TfRNi.\G the Rubber Cap. Fig. 4. Tapering Ends ok Rubber B.\rrei.. Fig. 5. Polishing the Rubber Pen Parts. 



cutting edge being slightly above the center of the work. The 

 cap is finish-turned with hand tools, after which it is taper- 

 reamed so that the hole in the cap will fit the tapered ends of the 

 barrel. 



The rubber barrel shown at B in Figure 1 is rough-turned in 

 a latlie in a similar manner to the cap. The next operation on 

 the barrel is to finish the two tapering ends ; one end must fit the 

 taper on the point section, while both ends must fit the tapered 

 hole in the cap. This is accomplished as shown in Figure ^■ 

 The barrel A is held in a chuck B in a small turning machine, 

 and the operator, by means of a flat hand tool C, turns down the 

 tapered ends to the required taper and diameter. The tool is 

 held on a rest D, and the taper is governed entirely by present- 

 ing the tool at the required angle. 



.\fter the front end has been turned, the barrel is reversed and 

 the rear end is turned taper and rounded ofif. The barrel is tlien 

 ready for reaming and tapping. The reaming is done with an 

 ordinary flat reamer in a speed lathe, while the tapping is accom- 

 plished with a tap provided with only two rows of teeth, or, in 

 other words, two cutting edges, the tap being practically flat. 



MAKIXr, THE POINT SECTION AND THE FEEDS. 

 The point section, which is marked C in Figure 1, is that part 

 of the pen which holds the nib and the feed. This is put on a 

 lathe and properly turned, and the threading is also done with 

 an ordinary flat chaser similar to that used by brass fini.^h- 

 e.rs. The thread on the point section of course must be perfect, 

 so that it will absolutely fit the thread of the barrel, permitting 

 no ink to escape. After the thread has been cut the front end is 

 reamed to fit the feed and pen point, and the external diameter 

 is taper-turned to fit the taper on the barrel. These lathes, 



POLISHING THE RUBBER I'ARTS. 



.^11 tlie rubber parts of the pen have now been made, but are 

 in a rough condition. The first polishing operation consists in 

 holding the rubber pen parts on arbors, and turning them around 

 by hand while they rest on a wet carpet-wheel buff on which 

 water is flowing. Ashes and powdered pumice stone are applied 

 to this carpel buff, which removes all tool marks but does not 

 give a glossy or polished appearance. 



The next operation consists in polishing the assembled rubber 

 parts on a cotton-wheel buff as show-n in Figure 5. The side \ 

 of this cotton-wheel is coated with rouge, and is slightly damp- 

 ened, while the other side B is dry and is not covered with anv 

 sort of polishing material. The operator holds the pen in both 

 hands, as shown, passing it back and forth over this cotton buff. 



."Xfter polishing, the pen is tested to see that it does not leak. 

 The assembled pen, without the feed or pen point, is placed in a 

 tank of water, and a syringe, which has a rubber tube that fits 

 tightly in the point section, is inserted in it. Then pen and tube 

 are placed in the water, and the bulb is pressed, forcing air into 

 the pen. If any bubbles are seen to rise in the water it is evident 

 that the pen leaks and must be repaired or discarded. 



STAMPING THE NAME ON THE BARREL. 

 .A.S far as the manufacturing operations are concerned, the 

 holder itself is complete, with the exception of having the name 

 stamped on it. This is accomplished in the device shown i:i 

 Figure 6. The barrel is placed on an arbor, on vv-hich it is 

 clamped, this arbor being connected to a square slide B working 

 against the tension of a spiral spring. The barrel rests between 

 two rolls C and D, the latter roll having the stamp cut in relief, 

 which is to be reproduced on the barrel. The handle E for operat- 



