Rant: Why I stopped using nylon brushes after a job in a 1920s house

I was on a job last month in a old house downtown. The owner wanted me to use a nylon brush on the clay flue liner. I did it like I always did, but when I looked up with my light I saw scratches all over the place. The nylon was too stiff for that old soft clay and it left marks that looked terrible. Now I only use poly brushes on anything built before 1950. Anyone else run into this with vintage flues?

2 comments

2 Comments

dylanh9712d ago

That 1920s clay is way softer than people expect (like, it practically crumbles if you look at it wrong). I had a similar wake-up call on a bungalow built in 1915 where the flue had that hand-made tile look, not the modern extruded stuff. The nylon brush chewed it up just like you said, left these fine grooves that caught soot like crazy on the next fire. Now I keep a separate set of poly brushes marked "pre-1950 only" in my truck (with a big red label so I don't grab the wrong one by accident). Also, try using a soft bristle brush with a smaller diameter than the flue, it gives you more control and won't dig in at the bends. That old clay is basically compressed dust, so treat it like antique brick and you'll be fine.

schmidt.eva12d ago

Why wouldn't you just use a poly brush on anything that old from the start?