Step 6 · Connect the Discharge and Drain Pipes
First, attach the plastic discharge tube (usually an L-shaped pipe) to the side of the disposal using the supplied gasket and flange/screws. Hand-tighten the screws, then give them a final quarter-turn with a screwdriver. Next, connect the dishwasher drain hose to the dishwasher inlet you prepared earlier and secure it with a hose clamp. Finally, connect the disposal's discharge tube to the P-trap. You may need to cut a section of straight PVC pipe with a hacksaw to get the alignment right. Dry-fit all the P-trap pieces first, then secure all slip nuts. Hand-tighten them, then give a final quarter-turn with channel-lock pliers.