showing a new wc the ropes with pole system yesterday, came round to pack away when i noticed my brush was brown all over!! without knowing it he had just cleaned a freshly stained ( as in creosote) window frame! first thought was knackered brush. used some chewing gum remover( solvent) on it. got a lot of it off but still not sure if it will be ok. has anyone had similar experience. if so how did you clean it?