Tests were conducted to compare the performance characteristics of school chairs constructed with pinned but unglued round mortise and tenon joints with those of chairs with glued but unpinned joints. Chairs with 0.125-inch cross pins in 0.723-inch diameter tenons developed over 90 percent of the strength of the chairs with glued tenons, whereas chairs with 0.31.3-inch diameter pins developed only 80 percent. Thus, results of the tests tend to indicate that chairs constructed with round mortise and tenon joints with small cross pins should provide nearly the strength and durability of comparable chairs constructed with glued joints, and therefore cross-pinning could be considered as an alternative method of joint construction in areas of the world where adhesives are in short supply.
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