UED ULM LOGS DAMAGED BY FUXGI BECAUSE LEFT TOO LONG OAK LOGS CHECKED BElAISK THEY WERE ALLOWED TO LIE 

 IN THE WOODS AFTER CUTTING TOO LONG BEFORE THEY WERE CUT 



cut with a knife ami not sawed from the bolts, there is a minimum 

 of waste from that source. 



It is rather unusual for bolts to be split, though this method 

 assures straight-grained stock, while the straightness of grain 

 of sawn bolts depends upon the skill of the man at the bolting 

 saw. Any advantage due to splitting is far outweighed by the 

 excessive waste which results in cutting the staves, as the tirst 

 two and last two staves from every split bolt must be culled be- 

 cause the sides of the bolts are so uneven. A comparative test of 

 the two methods was made by a manufacturer in New York state, 

 who found that nine cords of sawn bolts gave 12,000 %-inch 

 staves, while an equal amount of split bolts furnished only 10,000 

 staves of the same thickness. 



The stave cutter is or should be the most skilled employe in a 

 cooperage mill, because he must know how to handle each indi- 

 vidual bolt so as to get the best quality of staves in the shortest 

 time. At best there are numerous staves thrown out because too 

 defective to go into the regular grades. The number of such staves 

 increase in inverse ratio with the skill of the cutter. They are 

 generally used for fuel, though sometimes they are shortened for 

 kegs or part of them may be used to cover the stave piles in the 

 yard. An unavoidable waste at the stave knife occurs from the 

 thin slabs that are left and which are usually used for fuel. 



When staves are fresh from the cutter they are saturated with 

 water due in part to the greenness of the wood and also to the 

 steaming process which softens them. It is necessary that they be 

 dried quickly to prevent mold but not so rapidly that they would 

 be badly checked and warped. In piling the staves the piles 

 should be located on dry ground and should have air holes at the 

 bottom and openings at the top to allow a free circulation of air. 

 The injjividual piles should be separate and arranged parallel. In 

 no case should the staves be put directly on the ground, and the 

 upper tier should be covered with culled staves, bark or a roof 

 to afford protection from sun and rain. This will preserve the 

 bright appearance which is so essential in certain branches of the 

 trade, such as flour and sugar barrels. 



Warping and loss of circle can be prevented by choosing a ply 

 suitable to the weather conditions and to the tendency of the 

 species to warp. Care should be exercised to keep the pile per- 

 fectly level up to the top layer, which ma}- serve as a roof to shed 

 the rain. Since loss of circle is most likeh' to occur when the 

 staves are fresh from the knife the plan is sometim'es followed of 

 setting the staves loosely on edge for from a few days up to a 

 couple of weeks before placing them in the regular piles. This 

 increases the cost somewhat but very satisfactory results are 

 obtained. 



After staves have been air dried for sixty days or more, depend- 

 ing upon the locality and the season of the jear, they are jointed 



or trimmed so as to have proper bilge and smooth edges. If the 

 staves are not thoroughly seasoned the joint is liable to warp and 

 twist upon subsequent drying. The work of the jointer is very 

 important, but too often he is not as careful as he should be and 

 occasions excessive waste in trimmings or "listings," as they are 

 called, or bj' poor grading. Some woods are very hard to cut and 

 may contain knots, and there is a strong temptation for the jointer 

 to throw imperfect staves in the fuel pile, whereas with a little 

 more work and care the knots could be cut off and merchantable 

 staves secured. For instance, at a mill in Michigan out of two lots 

 of 17,000 staves each, 3,000 and 2,.500 staves, respectively, were 

 culled, a considerable number of which the jointer admitted could 

 have been saved. 



In sawing heading it is a common practice first to pull the bark 

 off the blocks by means of a rosser knife. In some mills, however, 

 the blocks are sawed with the bark on and then passed through 

 an old stave jointing machine to trim the edges. By this method 

 it is claimed that the boards have better edges, occupy less space 

 in the kiln^ are easier to joint later, and the work can be done 

 chiefly by a boy and an old machine. It has also been suggested 

 that heading be surfaced before kiln-drying, as it is easier done 

 then and is believed to hasten drying. 



Sawn heading boards are piled in the yard to air-season for 

 from sixty to ninety days before going into the kiln. Not infre- 

 quently, however, rush orders make it necessary to dispense with 

 the air-seasoning, and in the case of the denser hardwoods there is 

 likely to be considerable loss from checking and warping. This 

 can be overcome, in part at least, by proper regulation of the 

 drying by means of moist air and low temperatures at first. As 

 an example of the loss sometimes sustained may be mentioned the 

 statement of a mill superintendent in New York to the effect that 

 heading boards dried in the yard and then in the kiln would 

 average eighty per cent No. 1, while if dried in kiln direct from 

 the saw only fifty per cent No. 1 would be secured. This is ex- 

 plained by the fact that wood is a very poor conductor of heat 

 and if green material is exposed to a hot, dry atmosphere the 

 evaporation from the surface will be very rapid, while that of the 

 interior will follow slowly. For this reason, shrinkage, which al- 

 wajs accompanies drying, proceeds irregularly and the fibers are 

 torn apart. By regulating the humidity of the air in the kiln 

 the evaporation can be retarded until the wood is heated through 

 and through, so that subsequent loss of moisture will be gradual 

 and the shrinkage uniform. 



To secure good work at the heading jointer it is important to 

 see that the wheel is kept free from sawdust, that all parts are 

 equalh' balanced, that the knives are of equal sharpness and the 

 handling is always careful. When hardwoods are used it is often 

 difficult to obtain tight joints when matched, making it desirable 



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