2642 Chapter 22 



He found that the yields of deckboards from 1-inch lumber through surfacer, 

 cut-off saw, straight-line ripsaw, and chamfering machine was 68.4 percent. 

 Residue was 31.6 percent, which for each thousand board feet of oak lumber 

 amounted to 972 pounds on an ovendry basis and 1,576 pounds green. 



Yield of stringers manufactured from cants moving through the 4-inch surfac- 

 er to multiple trim saw, to gang ripsaw, to notcher was 58.8 percent. Residue 

 was 41.2 percent, which for each thousand board feet of oak cants input amount- 

 ed to 1,269 pounds for an ovendry basis and 2,055 pounds green. 



Perry (1976) analyzed these residues by type and found that the largest 

 percentage was shavings, and less than half of 1 percent was in culls, as follows: 



Proportion of total 

 Residue type residue, by weigh t 



Percent 



Shavings 66 



Trim ends 15 



Sawdust 10 



Edgings 9 



Cull __0 



100 



PALLET REPAIR 



Efficient unit-load handling with warehouse and exchange pallets requires a 

 well-organized pallet repair program. Frost and Large (1975) found, from in- 

 spection of 1,700 damaged pallets at four repair centers, that missing deck- 

 boards at pallet ends account for more than 50 percent of total deck damage; 

 longitudinal breaks and splits outside the stringer notches account for more than 

 80 percent of total stringer damage. 



Frost and Large found that two-man crews, each with its own work table, 

 pneumatic nail guns, hand tools, and repair parts, operating at a work station 

 served by forklift trucks, could repair 30 to 40 pallets per hour — 15 to 20 per 

 man-hour. 



One of the commercial repair and salvage companies dismantles pallets with a 

 hydraulic machine which holds one deck of the pallet stationary while forcing 

 the stringers away from that deck. Protruding nails are cut off with a grinder. 

 The company salvages enough lumber to repair some damaged pallets and also 

 to manufacture new ones. About 1 ,500 pallets are repaired per day; the company 

 serves an area about 200 miles in diameter. 



In 1974 a commercial pallet dismantling machine (an un-nailer) was intro- 

 duced and assembly line equipment has since been developed. By 1980, pallet 

 repair and recycling businesses were operational in most market areas. 



