Drain Rods are slightly flexible plastic rods, which attach end-to-end with screw fittings. Typically a set will consist of 6 to 10 rods, each about a meter long. They are used for clearing blockages from drains.
In addition to the rods, the set will contain three different end pieces. One (the plunger) is a disc of thick rubber, one (the corkscrew) is a metal corkscrew, and the other (the scraper) is a semicircular flap on a hinge - it can hinge towards the rods, but will stop when it has opened to 90 degrees.
Depending on the type of blockage, the correct end piece should be selected and connected to a couple of rods. The rods are then pushed down the drain, and more are screwed into place as necessary.
If the blockage happens to be the wrong side of a water trap, your rods will not bend around the corners. In that case, there should be a rodding eye in the ground somewhere above the trap. You can count the number of rods in use to estimate the distance, then go and look for it.
Pressure in a clockwise direction should be kept on the rods at all times, so they do not unscrew and become lost down the pipe.
The ends are selected for the following tasks:
- Plunger - for general blockages, the plunger can be used to violently disturb the drain contents in the area. This will often unblock the drain straight away.
- Corkscrew - if the blockage seems to be thick, so the plunger is ineffective, the corkscrew may be useful. Particularly with soft material like toilet paper, the screw is driven into the material and it is then pulled backwards out of the drain to be disposed of.
- Scraper - if the blockage is nearer to the house than the drainage cover, then it needs to be moved in a direction towards the rods, rather than away from them. The design of the scraper means that it will go past the blockage, then open out when pulled. This will draw the blockage back down the pipe towards the main sewer.
As the rods are removed from the drain, the clockwise pressure should still be maintained. As the number of rods outside the drain become unwieldy they should be unscrewed carefully from the set, and placed to one side.
After use they should be cleaned thoroughly with hot soapy water, then dried and tied together for storage.
The rods are identical to those used by chimney sweeps, and so by purchasing a chimney brush end, you have both sets of kit with only one set of rods to store.
Source: Mainly bitter experience.