TIGHT COOPERAGE 159 



Bending was formerly accomplished by steaming and drying on a form. 

 It is now done almost entirely by end pressure on a stave-bending ma- 

 chine and held, in shape by iron holders called " span dogs," which are 

 released when the staves are assembled in the finished container. Bend- 

 ing is used for beer staves and those intended for packages of considerable 

 bilge. Otherwise there would be a serious loss from breakage in wind- 

 lassing when the unbent staves are forced together for the upper truss 

 hoop. 



ASSEMBLirrG 



As a rule the assembling of tight cooperage stock into barrels, kegs, 

 etc., is done at or near the plant where the contents are put into them, 

 as was found to be the case in connection with the assembling of slack 

 cooperage stock. It is true, however, that more tight barrels are made 

 and shipped from large central cooperage plants to points of destination 

 where they are to be filled than in the case of slack barrels. This is 

 notably true in the case of turpentine barrels and to some extent with 

 beer kegs, whisky barrels and others. 



The assembling of tight cooperage stock demands the greatest care 

 and skill for the apparent reasons that (a) the finished barrel must be 

 sufficiently tight to prevent leakage, (b) the vessel must withstand trans- 

 portation to great distances together with considerable rough handling, 

 and (c) the barrel must often resist great internal pressure from fer- 

 menting liquors. 



The machinery, therefore, must be of the most elaborate, exacting 

 and specialized design. Special types of assembling machinery have 

 recently been invented and placed on the market which are vast improve- 

 ments over the old hand cooper or even the machinery in use ten and 

 twenty years ago. Most of them are great labor-saving devices. 



The machinery usually found in a modern up-to-date tight cooperage 

 shop consists of the following: A setting-up form with necessary truss 

 hoops, a power windlass, a heater, a trusser, a crozer, a head-setting form, 

 a lathe, a thin hoop driver, a heading-up machine, a bung borer and a 

 barrel tester. When the steel hoops are made in the plant it is essential 

 to have, in addition, a hole-punching machine, a riveter and a hoop flarer. 



In many of the plants the stock is brought in in bundles, enough 

 staves (usually i8) in one bundle for one barrel. First the staves are set 

 -up in a form by a " raiser " or " setter up," who sends them directly 

 to the steamers, where they are heated or steamed for from three to five 

 minutes to increase the flexibihty of the staves. Then they are " wind- 



