Removing a bathtub drain sounds simple. Usually it is. You grab a drain wrench or insert channel-lock pliers into the cross members and turn counterclockwise.

But if the cross members are corroded, broken, or missing — which happens on tubs that haven’t been touched in 20+ years — standard tools give you nothing to grip. This is where most people get stuck, sometimes literally staring at a drain for an hour and going nowhere.

Not sure what you’re looking at under there? See the complete bathtub drain plumbing diagram for a breakdown of every component.

Here’s the right tool and the right process.

Why Standard Methods Fail

The cross members (the X-shaped metal piece in the center of the drain) are what most removal methods depend on:

  • Standard drain keys insert into the cross and turn the whole drain
  • Channel-lock pliers grip two points of the cross
  • Flat-head screwdrivers inserted into the cross openings as a lever

All of these require intact cross members. Corroded old drains — especially brass drains in cast iron tubs that haven’t been touched in decades — corrode until the cross members are paper-thin. Try to apply torque and they snap off. Now you have no cross members and a smooth-walled drain hole.

At this point, standard tools are useless.

The Solution: Friction Drain Removal Tool

Bathtub Drain Removal Tool on Amazon

This tool works differently from any tool that relies on the cross members. Instead of gripping the center, it expands outward against the inner walls of the drain flange.

How it works:

  1. Insert the tool into the drain opening
  2. Turn the center bolt clockwise with a socket wrench — this expands the legs or tabs of the tool outward, pressing them firmly against the inner wall of the drain
  3. Once the tabs are engaged, continue using the socket wrench to turn the entire tool counterclockwise — this unscrews the drain from the drain shoe
  4. The friction grip between the expanded tabs and the drain wall is enough to apply the torque needed to break the drain loose

A good friction drain removal tool will work on a completely stripped, smooth-bore drain with no cross members at all.

What you’ll need:

  • Friction drain removal tool (also called an internal pipe wrench or drain extractor)
  • Socket wrench (most tools use a 1/2” or 3/4” drive)
  • Penetrating oil
  • Patience on old, corroded drains

Step-by-Step Removal Process

Step 1: Apply penetrating oil first.

Before you try to unscrew anything, soak the threads with penetrating oil — PB Blaster, WD-40 Penetrant, or similar. Pour it down around the edge of the drain where it meets the drain shoe. Let it sit for at least 30 minutes. On a drain that hasn’t moved in 20 years, let it sit overnight and apply a second dose in the morning.

Skipping this step means you’re fighting corrosion with torque alone. Penetrating oil softens the corrosion at the threads and dramatically reduces the force needed.

Step 2: Insert the friction tool.

Insert the tool into the drain opening. Make sure it’s centered.

Step 3: Expand the tabs.

Turn the center bolt clockwise until you feel resistance — the tabs are pressing against the drain walls. Don’t overdo it: you want them snug, not so tight you can’t turn the tool at all.

Step 4: Unscrew the drain.

Using your socket wrench on the center bolt with the tabs engaged, apply counterclockwise torque. On old drains, this can take significant force — brace yourself, work slowly, and make sure the tool doesn’t slip.

If it won’t budge after reasonable force: apply more penetrating oil, wait longer, and try again. A heat gun on the area around the drain (not directly on a refinished surface) can also help loosen corrosion — heat expands the metal slightly, breaking up rust bonds.

Step 5: Remove the drain flange.

Once it breaks loose, unscrew the drain fully by hand or with the tool. Pull it out.

What to Do if the Tool Still Can’t Get It

Occasionally a drain is corroded so badly it’s essentially fused to the drain shoe — not just the threads, but the joint. In these cases:

  1. Try a different (heavier duty) friction tool — quality varies a lot. Cheap tools may not provide enough grip.
  2. Apply heat more aggressively with a heat gun (not a torch near plumbing lines).
  3. Consider calling a plumber.

The last resort for a truly fused drain is cutting it — a rotary tool or oscillating saw can cut around the perimeter of the drain, after which the pieces can be extracted. This is messy and gets close to the tub surface. If you’re going this route, a plumber is probably the right call.

Installing the New Drain

Once the old drain is out:

  1. Clean the drain shoe seat thoroughly — remove all old plumber’s putty and any corrosion
  2. Inspect the drain shoe for damage — if the threads are stripped or the shoe is cracked, that’s a more involved repair (plumber territory)
  3. Apply fresh plumber’s putty to the underside flange of the new drain
  4. Thread the new drain in clockwise by hand until it starts to seat, then snug it with the drain tool — do not over-tighten
  5. Clean up excess plumber’s putty that squeezes out

Replacement Bathtub Drain on Amazon

Standard drain flanges are 1.5 inches in diameter for most tubs. Confirm your drain shoe thread size before buying — most residential tubs use a 1.5” 16 TPI (threads per inch) standard, but there are variations.

Why You Need to Remove the Drain for Refinishing

If you’re refinishing the tub, the drain must come out. Not taped around — out.

Taping around a drain leaves uneven edges where the coating terminates at the tape line. The tape edge never produces a clean professional result, and the coating will eventually lift at that edge. Removing the drain lets you coat right over the drain hole opening and reinstall the drain afterward for a clean, properly sealed finish.

This is why investing 30 minutes in removing a stuck drain is worth it during a refinishing project.