I work for a company that has a restaurant franchise. They are strongly considering buying the techs electric sewer snakes fairly large one with half inch cable. We are not plumbers by any stretch of imagination. We are AC and kitchen equipment service men. We know from when we call plumbers in to clean out blockages there is some technique to using these things.(feeling when it is in a turn or hitting a clog) I have heard it is possible to break fittings or traps in the floors or cause other damage with these machines. If anyone could assist me with some information to combat their idea it will be greatly appreciated. We have good relationships with the plumbers we use in each of our areas and would like to continue to give them business. In addition, we don't want the added work load as this was not in our job description when we started with the company.