CIPP Liner Overshot Fixes

“I shot a liner too long and it ended up 4” in the sewer main in the street. I figured it would be okay as it bulged out when it got to the main being unstrained by the host pipe and thought ‘great, I’m insuring no roots from growing into the joint where it connects to the main’. Figuring it was okay was short lived as I got a call from the city a few days later asking me if I was the contractor who overshot a lateral liner. Admitting I was and then explaining with pride that I’d sealed the connection with the expanded liner fell flat when the city told me that the 4” overshot caught a slug of flushable wipes and backed up the sewer main. When their crew got the line opened up they discovered the protrusion into their main and not only wanted me to remove it immediately but to also pay for their crews time to open up the sewer that was plugged where this overshoot occurred. I called a sewer contractor who cut the protrusion with a root saw from the upstream manhole. Do you have a lower cost way to cut the overshot liner if it ever happens to me again?”

I’m sure that was a costly adventure that you don’t want to repeat any time soon. There are several methods to remove an overshot liner and obviously there are price differences involved in both cost of tooling and labor costs regarding the time it takes.

Let’s start with the least expensive tool cost first however this method may take some time and may not always work depending on the orientation of the “Y” or “T” as you enter the main. If you are opening a 4” or 6” overshot, you can purchase a 4” by 6” or a 6” by 8”expandable blade made by Rigid. This device is found at most cable machine suppliers. The tool is fitted to a standard cable machine and is set up as follows. First, sharpen the edges of the tool so that as you turn the blade, the outer edges of the blade will rub on the outside of the end of the liner that is protruding into the main. You run the tool beyond the end of the liner, begin turning the cable machine and slowly retrieve the cable allowing the sides of the tool to peel the liner like you would an apple. Here’s a picture of the tool. This tool is less than $150 and can be used with your conventional cables. It may not orientate itself correctly as the angle may not trip one side completely back to the tie-in.

Obviously a root saw that you saw from the mainline sewer contractor using is another option, although you may need permissions and pay fees to open the manhole from the sewer agency governing your particular sewer. These devices are usually fitted to a jetting machine and water driven. Here’s a saw:

We sell a cutter that attaches to a high speed cable machine and as it’s spun blade fling out by centrifugal force and cut the liner material. We offer a 4” and 6” cutter, however you can’t use a 6” cutter through any sections of 4” pipe. Here’s a picture of the cutter.

The next tool you may consider is a Cyclone chain knocker. This tool will allow insertion into a 4” pipe that needs to trim off a 6” liner that was overshot. This tool attaches to a high speed cable machine:

The next tool ratchets up your costs. This tool can reinstate lateral connections from the lined pipe as well as cutting the end of the liner at the overshot site IF the line is straight . Multiple turns and pipe diameter changes make this tool difficult or impossible to use:

The final offering is a cutter than will negotiate multiple turns, diameter changes, and challenges that cutting off the overshot affords you. These cutters will require an air source of 70CFM or more and is a robust tool that requires some training and enough work to employ the tool:

For more information on these tools or for pricing of them, call us at +1-888-354-6464 or write us at

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