The above is one of the most common topics that we are contacted over as the hapless and frustrated home owner trying to save a few pounds has now not only got a blocked drain but he has lost his newly purchased or borrowed drain rods in the system as well.
Why Drain Rods Get Stuck Or Lost
The main cause of rods becoming detached during the drain clearing process is that they simply unthread themselves, the rods purchased at the large DIY houses and builders merchants screw together and all that thrashing about in the drain can cause the rods to spin and undo.
Similarly if the plunger or screw attachment become lodged in the blockage or on a sharp bend panic ensues and invariably the rods are pushed, pulled and twisted in all directions, unfortunately twisting the rods anti-clockwise unscrews them and the law of sod says that it will be the joint halfway down the system that separates first and leaves you holding just three of the six rods you started with.
Drain Rod Plunger Attachment
Rubber drain plunger heads are the same internal diameter as the drain itself or slightly larger, they have a tendency to fit snugly in an open joint and for some reason they will pass through a badly stepped joint fairly easily but they don`t want to pass back the same way quite as easily. Depending on the make and age of the rubber it should be an easy enough job to recover them but as mentioned earlier panic sets in and and five minutes of thrashing around results in the rods separating.
If you are pushing a 100mm plunger through a 100mm drain and you come to a connection onto a 150mm sewer then obviously as the plunger enters the larger diameter drain everything goes slack, the trick is then to pull the plunger back into the smaller diameter pipe. This can take some doing as the drain rods will be lay in the base of the smaller pipe meaning that half of the plunger will be pulling against the wall of the larger drain, again with a little pulling and twisting in the right direction the rods can be easily retrieved
Rods can get stuck when they have passed around several sharp bends or when the plain end of a rod finds its way into the sub-soil via a displaced joint. Over zealous rodding will punch a hole through a bend such as a rest bend at the base of a soil vent pipe particularly if the system is made up of vitrified clay ware and again the rods become lodged in the sub soil.
Occasionally we find rods that have snapped in two either due to age or misuse, old cane rods that have been in the corner of the garage for 30 years should go on the skip and modern rods will also snap when twisted to the point of destruction.
How We Get Lost Drain Rods Out
There are several techniques for removing drain rods from a system without the need for excavation works, they are as follows;
If the rods have just twisted and separated then a high pressure water jetter may well flush them out, ideally this requires access from a downstream position and no attachment on the end of the rods.
If the rods have unscrewed they can be retrieved by using a camera, a set of similar rods and with the dexterity that a heart surgeon would be proud of we can re-screw into the lost rods and pull them back in most cases.
If the rods have snapped then by using steel root cutting rods along with a retrieving head it is possible to anchor onto the offending objects and retrieve them.
Other techniques include forming a slip noose using fishing wire or similar and placing it over the rods with the aid of another set of drain rods, a drain camera and some nimble hand, eye co-ordination, and finally fishing wire along with some barbed hooks placed on the end of a set or steel rods and spun until it grips the stranded drain rods.
All the above have been used and worked at some time or other, every job is different but these techniques are certainly worth a try prior to carrying out expensive excavation works.
Why Don`t Drainmen Get Their Drain Rods Stuck
We do, there are situations where the rods leave the drainage system and become lodged in the sub-soil or a rod becomes wedged in a displaced joint but what you shouldn't find with a drainage contractor is the rods unscrewing because we use lock fast rods (see image) that are designed to stay together when twisted in either direction.
They come in 1, 1.5 and 2mtr lengths and are more expensive than traditional rods which is why you are unlikely to see them on sale at the DIY outlets.
There comes a point when drain rods are not suitable for clearing a blocked drain, this can be due to available access into the system, the distance of the blockage from the access point and the cause of the blockage itself.
Homeowners and DIYers are probably a bit more persistent when using drain rods than a drainage contractor and they will force them around bends, traps etc. where a contractor would use a high pressure water jetter or mechanical rod, likewise a contractor will be able to tell when he comes to an obstruction using rods whether he is likely to clear the system sufficiently enough or if in the case of tree root ingress or a build up of fat and grease its time to get the jetting machine working.
We do, there are situations where the rods leave the drainage system and become lodged in the sub-soil or a rod becomes wedged in a displaced joint but what you shouldn't find with a drainage contractor is the rods unscrewing because we use lock fast rods (see image) that are designed to stay together when twisted in either direction. 
