Sometimes, you may need to remove the sink drain flange, the rubber trim seal on the sink bowl, to do plumbing or drain repairs, but they get stuck, occasionally. Flanges get stuck for various reasons, such as accumulation of rust from the hardware, glue used for installation, or debris. Try to remove the stuck drain flange yourself by following these steps, before you call a plumber.

Prepare to Remove the Flange

To remove the flange, gather:

• work gloves
• eye goggles
• hammer
• putty knife
• utility knife 
• heavy-duty screwdriver
• ten-inch tongue and groove pliers
• sixteen-inch tongue and groove pliers
• pipe wrench
• penetrating oil
• chisel (optional)
• hair dryer (optional)
• hacksaw (optional)
• two-by-four small wood board

Remove all items from under the sink, and shut off the water supply, which is commonly located under the sink. Turning off the water helps to prevent someone from turning on the sink. Lay a cushion or lounge chair pad on the floor, to make working under the sink more comfortable.

Detach the Drain Pipe and Flange Lock Nut

Spray the sink threads on the bottom with lubricant, and let it stand for the suggested time. Grasp the coupling nut on the bottom of the drain pipe and flange base with the jaws of the ten-inch pliers, and rotate it to the left.

Remove the pipe, and lay it aside. Sometimes, you may need to rotate the nut slightly to the right first, to break sediment. 

If the drain spins, have an assistant hold the inside of the drain opening with another pair of pliers, holding a screwdriver between the handles. Remove the lock nuts at the bottom of the sink bowl, in the same manner, using the sixteen-inch pliers.

If you have trouble removing the lock nuts, hold a hair dryer turned on the highest setting close to the nut, then try to remove it again. Use the pliers to twist the lock nut tabs, which should loosen the nut. 

Otherwise, insert a chisel on one lock nut tab, and lightly hit the opposite end with the hammer, to break the sediment or rust. If nothing else works, saw the nut off the basket, cutting diagonally through the plastic or metal.

Remove the Flange

Hold the small board vertically against the bottom of the basket, and tap it with a hammer, but not too hard. The tapping should help lift the flange enough to remove it with a putty knife. Slide the putty knife between the sink and the flange, and carefully lift the flange from the hole.