2570 Chapter 22 



Some obstacles to implementing this concept include cost of matching la- 

 minae lengths and widths prior to lamination, loss of wood in surfacing inter- 

 faces to be glued, and cost of lamination. 



MILLWORK 



The scarcity of clear hardwood lumber in lengths and widths traditionally 

 used for hardwood mill work has sharply restricted its use in residences. The 

 magnificent hardwood solid panellings and mouldings popular in homes built in 

 the 19th and early 20th Century have largely been replaced by plywood panel- 

 ling and painted or overlayed softwood mouldings of smaller dimensions . Use of 

 hardwood millwork in the 1930's dropped sharply from that in 1928, but has 

 since increased somewhat (fig. 29-25). 



In these final decades of the 20th Century, hardwood millwork is largely 

 confined to church architecture (oak pews, for instance), executive offices, bank 

 lobbies, luxurious architect-designed homes, and top-grade store fixtures. Pre- 

 finished, tongue-and-groove, end-matched panelling of thin solid hardwood is 

 still sold commercially, but competition from foreign and domestic plywood is 

 intense. 



Various ideas have been advanced to utilize low-grade hardwood logs for 

 panelling, but few have proven commercially successful. For example, Heebink 

 and Compton (1966) made panelling (fig. 22-3) from low-grade oak logs by 

 sawing thin unedged boards at the headsaw, planing them to 0.6-inch thickness, 

 press-drying (figs. 20-32 and 20-33) and double-surfacing them to 7/16-inch 

 thickness, and then machining matching tongues and grooves on ends and sides 

 to yield face widths of 2, 3, 4, and 6 inches and lengths of 2, 4, 6, and 8 feet. 

 They found that press-drying of oak produces a color about the shade of chestnut 

 or light walnut and accentuates character marks. 



Peter and Page (1957) experimented with character-marked interior panelling 

 made from low-grade logs of several southern hardwoods and found that sand- 

 blasting produced a pleasing visual effect; the red oaks were easiest to treat by 

 this method. Open knots or defects were backed with heavy black paper and 

 boards were treated with various fillers and tinted finishes. They concluded that 

 the panelling, while attractive, still looked like what it was — a low-grade board. 

 Surface treatment or color blending is needed to subdue defects. Such an effect 

 can be obtained by hammering or pressing indentations into wood that has been 

 previously filled and finished. 



More recently, Hansen and Gatchell (1978) and Gatchell and Peters (1981) 

 showed that joints in hardwood lumber end-joined in a sine-wave pattern are 

 stable and virtually undetectable by most people if grain patterns are matched. 

 This serpentine end matching technology, described by Gatchell et al. (1977) 

 and Coleman (1977) shows promise for utilization of short clear cuttings in high 

 quality millwork. The sine-wave joint is not structural, however; it is best suited 

 for application in panels (fig. 22-4) 



