Auger Cable Sizer: pick the cable, head and machine before you start

01 /What does the Auger Cable Sizer do?

The Auger Cable Sizer matches an auger setup to a specific drain line. You tell it which line is blocked, roughly how far the clog is from where you will enter, and what the clog is likely to be. It looks up the cable for that line in the site's auger cable size chart, checks whether the chart's typical length reaches your distance, picks a head for the clog type, names the machine class that carries that cable, and raises a flag when the combination is one most homeowners should hand off.

It is a lookup plus a handful of fixed rules, not a model of your house. Every output traces back to the chart row you picked or to one of the rules described on this page, so you can check its reasoning line by line. It does not estimate prices, and it does not know your pipe material or the exact route your drain takes.

02 /What do you enter?

You enter three things, each from a short list.

• Line: bathroom sink 1-1/4 in; kitchen sink, tub or laundry tray 1-1/2 in; shower, standpipe or small floor drain 2 in; stack, toilet branch or floor drain 3 in; building drain or lateral 4 in; larger lateral 5 to 6 in.
• Distance to clog: under 3 m; 3 to 8 m; 8 to 15 m; 15 to 30 m; over 30 m.
• Clog type: hair or soap; grease or food; paper or wipes; roots; hard object; unknown.

If you are not sure which line is blocked, run the Clog Locator first; it narrows the clog to a fixture trap, branch, stack, building drain or lateral from which fixtures are affected. For distance, measure along the likely pipe route from your access point, not in a straight line across the room or yard. The auger cable size chart explains how to tell pipe sizes apart by outside diameter if you are unsure whether a line is 3 or 4 inch.

03 /How does it choose the cable and length?

The cable and length come directly from the chart row for the line you pick. Each row gives a drum cable size, a sectional cable size (or none, for small fixture lines) and a typical length range. The chart lists lengths in feet, and the sizer converts at 1 m ≈ 3.3 ft so they can be compared with the distance band you chose in metres.

If the distance you choose runs past the upper end of that row's typical length, the result recommends a longer cable, a sectional machine or a professional. For example, a bathroom sink clog 8 to 15 m away is beyond the 25-ft top of the 1-1/4-inch row, and a tub line clog 15 to 30 m away is beyond the 35-ft top of the 1-1/2-inch row. Both results tell you the clog is not where a fixture-sized tool can reach, which usually means it is not really a fixture clog.

Where a distance band straddles the top of a row, such as a 2-inch line with a clog in the 15 to 30 m band, treat the result as a prompt to measure more carefully and to add the roughly 25 percent extra cable that bends and slack consume.

04 /How does it choose the head?

The head follows the clog type you pick. The rule is to start with the head that deals with the most likely material and, where the first head is only an opener, to say what comes next.

The roots note exists because tree roots enter through joints in buried pipe, which in a house means the building drain and lateral. A 1-1/4 to 2-inch fixture line that seems to have roots usually has hair, soap or fibrous debris that looks rooty, or the clog is further downstream than you think. The hard-object rule exists because pushing a toy, a cap or a broken head deeper usually wedges it at the next fitting. Head sizing and the step-up sequence are covered in auger cutting heads.

05 /How does it choose the machine class?

The machine class follows the line size, because the cable a line needs decides which machine can carry it.

• 1-1/4 to 1-1/2 in: hand drum.
• 2 in: hand drum or small drum machine.
• 3 in: drum machine.
• 4 in: drum machine or sectional.
• 5 to 6 in: sectional, flagged as a professional job.

Machine classes are described in types of drain augers. The sizer does not tell you whether to rent or buy; renting vs buying an auger and which drain snake to buy cover that decision.

06 /When does it say to call a professional?

The sizer raises a professional flag in three situations. Each is a point where the equipment, the injury risk or the likelihood of a structural cause goes beyond what a household rental reasonably covers.

1. A 4-inch or larger line with roots. Roots in a building drain or lateral mean an open joint or crack, heavy sectional cable, a root cutter and ideally a camera. The clearing is maintenance; the entry point needs a repair decision.
2. Any clog more than 30 m away. That is beyond the typical length of most household-scale cable and usually means the clog is far out in the lateral or near the municipal main.
3. Any 5 to 6-inch line. These take sectional cable of 7/8 or 1-1/4 inch, which stores enough torque to cause serious injuries.

07 /What are the sizer's limits?

• No toilet trapway option. Toilet clogs inside the porcelain call for a closet auger, not drum cable; see what size toilet auger you need. The 3-inch toilet branch row is for the pipe below the toilet.
• It does not know your pipe material. Old clay, bituminous fibre and corroded cast iron call for gentler heads than the same line in ABS; see can a drain snake damage pipes.
• Typical pairings, not a standard. Manufacturers publish their own capacity charts and the ranges overlap. Check the chart supplied with the machine you own or rent.
• It assumes a clog. A blocked vent, a frozen line, a fouled backwater valve or a surcharged municipal main produce clog-like symptoms that no cable fixes.
• It does not choose your access point. The same line can be reached from a fixture, a cleanout, a floor drain or a toilet pull, and the best one is usually the closest upstream opening with the straightest path.

08 /How should you use the result?

1. Locate first

   If you do not know which line is blocked, use the Clog Locator before the sizer.

2. Measure the route

   Estimate distance along the pipe from your access point, then add about a quarter for bends.

3. Run the sizer

   Pick the line, the distance band and your best guess at the clog type. Choose unknown rather than guessing.

4. Check the machine's own chart

   Confirm the cable size against the manufacturer's chart or the rental counter's advice.

5. Start with the suggested head

   Probe, sample what comes back, and step up only if the evidence supports it.

6. Respect the flags

   If the result recommends a longer cable, a sectional machine or a professional, stop there rather than forcing a lighter setup.

If the result points to a professional, you can request quotes and ask each contractor which cable and head they plan to run, whether they will go to the municipal main, and whether a camera is included. Technique for the most common jobs is in how to snake a sink, how to auger a floor drain and clearing a main line from the cleanout.

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