I have 27 feet of stainless class A chimney. I have 30 feet of Rutland fiberglass cleaning rods and a 6" metal brush that I use on my flue. It's a straight shot down from the top. I then remove the clean out cap in the basement and remove the debris from the bottom of the "T" where my wall thimble and stove pipe connector connect. I will be visiting my parents in a few weeks and need the proper stuff clean Dad's chimney. The house is a 30 x 45 ranch. The basement is divided in 2 halves that are 15 x 45. The front half is mechanical area / unfinished with the oil boiler sitting in the RR corner. The rear half is finished and in the RF corner is a large brick hearth that has a huge Quadra-Fire insert. The brick chimney is external to the house foundation and contains two 6 x 8 clay flues. When the insert was installed he had a corrugated stainless flex liner installed inside the clay flue. It is about 21 feet long from the top down to the insert. The top is about 17 feet straight down to the old "smoke shelf" area, then bends at about a 15 to 30 deg angle and heads to the top of the insert. They had to egg shape it slightly to about 5 x 7 in order to get it to fit. What is the best cleaning rods and brush to use on such a set up? I'm not sure if my Rutland fiberglass rods will bend that much? Are you are supposed to used nylon brushs on the flex liner? Should I get a larger brush and trim it down to the 5 x 7 size? Due to the egg shaped liner, a 6" round seems like it won't clean effectively?