2980 



Chapter 24 



It is likely that industry will make structural flakeboards from mixtures of 

 southern hardwoods, rather than from single species. Price (1974) and Hse et al. 

 (1975) demonstrated the strong effect of species mix on IB (table 24-15). Using 

 lathe flakes of white oak (a very dense wood) and sweetgum (a low-density 

 wood) Price found that if panel density was fixed, IB was correlated with the 

 proportions of the species mix. Hse's findings were similar; he used veneer 

 flakes with fixed panel density of 46 pounds/cu ft (table 24-15). Results with 

 mixtures of white oak with other low-density southern hardwoods are similar to 

 those for sweetgum (table 24-16). 



3 - 



a. 



o 

 o 



CD 



2 - 



0.5 



1.5 



2.0 



COMPACTION RATIO 



Figure 24-40. — Relationship of compaction ratio to internal bond strength. Data points 

 represent single-species panels of sweetbay, red maple, sweetgum, black tupelo, 

 white ash, southern red oak, hickory, post oak, and white oak. Dashed lines indicate 

 the compaction ratio corresponding to an attainble average of 70 psi IB. (Drawing 

 after Hse 1975c.) 



