— MAIN BODY TUBE 



WBGHT STAND ASSEMBLY 



A 



-CORE CATCHER 

 -CORE CUTTER 



— PVC CORING TUBE 



Figure L-9. 



The Hydro-Plastic (PVC) piston eorer 

 assembly. 



Electric drill ; 



Saw; 



Adjustable end wrench. 



Step 1. Secure the drill jig flush with the end 

 of a section of (PVC) coring tube, and drill %- 

 inch holes in tlie coring tube according to the 

 jigpattern. 



Step 2. "With the main body tube in a horizon- 

 tal position on the deck, secure the coring tube 

 to the assembly with hex-head bolts. 



Step 3. Insert the end of the lowering wire 

 through the main body tube and the (PVC) 

 coring tube, and attach it to the piston assembly. 



Step 4. Pull the piston back into the (PVC) 

 coring tube. The piston should be about 1 inch 

 behind the leaves of the core catcher. Insert the 

 core catcher. Slip the core cutter over the end 

 of the (PVC) coring tube, and tighten the set- 

 screws until the core cutter is secure. 



Step 5. Attach the wire clamp of the release 

 mechanism to the lowering wire tlie desired free- 

 fall distance above the corer bail ; hook the corer 

 bail in the release mechanism slot ; and insert the 

 safety pin. 



Step 6. Fasten the trigger weight line to the 

 end of the arm of the release mechanism. The 

 overall length of the trigger weight line should 

 equal the total length of the corer plus the 

 amount of wire allowed for free fall, then at- 



tach the tripping weight (approximately 80 to 

 100 pounds) . 



Step 7. Swing the corer outboard and suspend 

 it over the side in a vertical position; then at- 

 tach four to six cast lead drive weights to the 

 weight assembly stand, and secure them in place 

 with the weight collar (fig. L-10) . 



Step 8. Tape the bight of free-fall wire be- 

 tween the corer and the release mechanism to 

 the weight assembly stand, to prevent kinking 

 and hanging up, remove the safety pin, lower 

 the assembly to the water surface, set the meter 

 wheel to zero, and commence lowering the corer. 



NOTE : To rig the Hydro-Plastic corer as a 

 gravity corer do not use the piston assembly and 

 substitute the following for step 3 : Connect the 

 free end of the lowering wire to the bail of the 

 corer, insert the core catcher, and secure the 

 cutting edge with the setscrews. A tripping re- 

 lease mechanism can he, used if desired. 



L-25 Obtaining the Hydro-Plastic (PVC) 

 Piston Core. — Lowering slioukl be accom- 

 plished in accordance with instructions in L-29, 

 Obtaining the Core. 



Figure L-10. Attaching weights to PVC corer. 



L-26 Retrieving the Hydro-Plastic (PVC) 

 Corer. — As soon as the winch is stopped, note 

 the amount of wire out and commence hauling 



L-11 



