Types of drain augers, from a closet auger to a sectional machine

01 /What types of drain augers are there?

Drain augers fall into six practical classes, sorted by the pipe sizes they suit and how the cable is stored and driven. The table gives the typical pairing; exact ranges vary by manufacturer, so check the chart printed on or supplied with your machine.

Not sure which part of the system is blocked? Run the Clog Locator first; it recommends a class and cable size from your symptoms.

02 /What is a closet auger used for?

A closet auger (toilet auger) is a short cable inside a rigid, curved tube with a crank handle on top and a rubber or vinyl sleeve at the bend. The tube is shaped to sit in the bowl and aim the cable straight into the toilet's built-in trapway, while the sleeve keeps steel off the glazed porcelain.

It is the only type of auger that should go into a toilet bowl. A hand drum auger fed through the bowl tends to coil in the bowl, catch in the trapway's tight curves and scrape grey marks into the glaze that do not scrub off. Closet augers come in roughly 3-foot and 6-foot lengths; the longer version can reach past the trapway into the closet bend below the floor.

Technique, stop conditions and what to do if the object will not come out are in how to auger a toilet without scratching porcelain. Choosing a length is covered in what size toilet auger you need, and when a plunger should come first is in toilet auger vs plunger vs drain snake.

03 /When is a hand drum or drill-powered auger enough?

A hand drum or drill-powered auger is enough for any clog within a few metres of a sink, tub, shower or laundry standpipe in pipe of 2 inches or smaller. These tools carry 1/4-inch cable, occasionally 5/16-inch, in an enclosed plastic or metal drum. You pull out cable, lock it with a thumbscrew, crank or drill, then unlock and pull more.

• Strengths: cheap, light, low stored torque, easy to control, gentle on plastic traps and chrome.
• Limits: the thin cable coils up in anything larger than 2-inch pipe and lacks the stiffness to push through dense clogs more than a few metres away.
• Drill-powered versions: faster and less tiring, but a cordless drill on high speed can kink thin cable in seconds. Use low speed and short bites.
• Auto-feed hand tools: a trigger advances and retracts the cable. Convenient, but keep the same caution about stopping when the cable loads up.

04 /What is a drop-head auger?

A drop-head or flat-top auger is a compact powered machine with the drum lying flat and the cable exiting through a short guide tube at the top, so it can sit on a counter or in a vanity and feed into a small line at a low angle. Plumbers use them for kitchen and bathroom branches, commercial hand sinks and urinals, where a full drum machine would be too heavy to lift into position.

They usually run 5/16 or 3/8-inch cable and handle 1-1/4 to 3-inch lines. For a homeowner, the relevant point is that a drop-head machine is a genuine powered auger with real stored torque; it deserves the same safety discipline as a floor-standing drum machine.

05 /How does a drum machine work?

A drum machine is an electric auger with the whole cable coiled inside a large rotating drum mounted on a frame or dolly. The motor spins the drum, the cable spins with it, and you feed cable out of the drum's front guide either by hand or with a power feed. It is the machine most drain cleaners bring for branch lines, stacks and building drains, and the one most rental counters stock.

• Cable sizes: 3/8-inch for 1-1/2 to 3-inch lines, 1/2-inch for 2 to 4-inch lines, and heavier drums with 5/8 or 3/4-inch cable for 3 to 6-inch laterals. Some machines accept interchangeable drums.
• Reach: commonly 50 to 100 feet depending on cable diameter, since thicker cable takes more drum space.
• Power feed: a lever-operated feed pushes and retracts the spinning cable. It keeps hands further from the cable, but it can also drive a stuck head until the cable loops, so release it at the first sign of loading.
• Inner-core cable: heavier drum cables often carry an inner wire core that resists kinking and stretching.

The disadvantage of a drum is that a kink or tangle can happen inside the drum where you cannot see it, and running in reverse can make the cable snarl in the drum. For main-line technique see clearing a main line from the cleanout.

06 /Why do pros use sectional machines for main lines?

Pros use sectional machines for main lines because short, heavy cable sections carry more torque, reach further, and can be added one at a time until the head reaches the clog. A sectional machine does not store cable; it spins whatever length is fed through it. Sections are commonly 7.5 or 15 feet long with quick-connect couplings, and common cable sizes are 5/8, 7/8 and 1-1/4 inch.

Two hazards are specific to sectional cable. Running in reverse can unscrew or uncouple sections inside the pipe, leaving cable behind; and the heavier cable stores enough torque to break a wrist if the head binds and the operator's hand is wrapped around it. That is why most homeowners hire sectional work out; see renting vs buying an auger.

07 /How do you choose the right auger type?

1. Identify the fixture group

   One fixture, one room, one floor, or the whole house. The main line vs branch clog guide shows how to tell.

2. Estimate the pipe diameter

   Look at the trap, the cleanout plug, or the stack. Most Canadian houses have 1-1/4 to 2-inch fixture drains, a 3-inch stack and a 4-inch (100 mm) building drain.

3. Measure the distance

   From your access point to the likely clog, plus slack for bends. Buy or rent enough cable to reach with a margin.

4. Match the class

   Use the table at the top of this page and the auger cable size chart.

5. Be honest about control

   If you have never run a powered machine, a main line is a poor place to learn. The drain is not going anywhere; your hand might.

Once you have the class, choose the head. Auger cutting heads and when to use each covers the options. The Auger Cable Sizer turns your line, distance and clog type into a machine class and cable, and which drain snake to buy covers the specs worth paying for. If the job is past what you want to handle, request quotes and ask each contractor which machine and cable they plan to use.

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