I decided to make some coroplast panniers to put on my beater for grocery runs but I think I need a little help. Each wall of the pannier is reinforced with two pieces of coroplast held together with zip ties. I originally wanted a hook mounted system but everything I tried was not sturdy enough. I've decided that I'm probably just going to have to attach them to my rack with zip ties but I'm slightly concerned the weight of groceries, etc will tear the walls of the coroplast. Anyone know what I can use to reinforce it? I was thinking of adding some more coroplast to the wall being attached and maybe some duct tape around the whole pannier. Suggestions welcome!