Plastination of Large Specimens Robert W. Henry, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN 37901, USA
Specimen Preparation is of foremost importance. Large containers are necessary to process large specimens (fix, rinse, bleach, dehydrate). Fixation and Dehydration Tanks (Vats) with Specimen Baskets, which fit snugly into them, should be the same size as the plastination chamber and fabricated from 18 ga (1.2 mm) stainless steel for durability. Therefore, any specimen which fits into your basket will fit into you plastination unit. Specimen Baskets facilitate handling specimens, aid maintaining the desired conformation of the specimen, and aid draining and submerging the specimens. To stiffen the basket, the top side edges are hemmed in and the top end edges are turned in 100° to serve as a handle. Top and bottom grids are cut from aluminum or SS mesh. To stiffen the Fixation and Dehydration Tanks, the top edge should be hemmed outward. Either direct drive or belt driven pumps provide adequate vacuum for large Plastination Units which may be constructed of 1/8 to 1/4 inch (6 mm) stainless steel or steel. However, internal and external bracing may be needed depending on the size of the unit. It is desirable to prime the steel and coat with epoxy paint. Reinforced fiberglass may be used, however, no benefits have been found from using fiberglass. A stainless steel liner, constructed similar to the vats, is recommended to protect the epoxy coating of the steel from methylene chloride. Smaller liners and baskets may be used to confine the polymer into a smaller area, thus decreasing the quantity of polymer required. A Vacuum Reservoir aids sealing larger plastination chambers. Empty refrigerant (freon) containers, a smaller vacuum chamber which seals easily, or utilizing the vacuum from another larger vacuum chamber which is in use are good vacuum reservoirs.