Decent size old saucepan lids, curved ones, especially stainless steel ones can be adapted to make splendid chimney coolie hats. All you need is= The pan lid, a length of 13mm copper tube, 6 pop rivets and pop rivet gun or wee nuts and bolts.
First of all cut 3 10'' lengths of the copper tube and flatten their whole lengths into strips in a vice or by hammer on a block. In the vice bend in the appropriate places a crank in each strip that will sit on the chimney rim. Bend a little an inch at one end of each strip to the profile of the underside of the pan lid and mark their positions thereon equidistant apart and drill an offset hole right through each and through the pan lid. Pop rivet or bolt up all three strips. Twiddle the legs to get them all facing the centre and drill another three holes next to the first ones and rivet or bolt up for good. Offer up onto your chimney and gently bend the legs until the cranks sit snug and square on the chimney rim. Retain the pan lids handle or knob for artistic effect.