Could just use a soldering iron and heat up the plastic welds so they melt again and pull everything apart , then when you're ready to put it all back together again just do it again, just heat up the plastic along the edges where things meet with a soldering iron and make you're own welds shouldn't need any plastic weld rods just spread the plastic across the gap as it melts to join it , do it in a well ventilated place if you can though because it will bloody stink ??