I've purchased a very well used scythe last year and have been using it around our homestead for various cutting of grasses weeds and very small brush. I read in the forum that there is a brush blade available and I'm wondering if all scythes can have interchangeable blades or just some. Also, I've been using the blade that was on the scythe when I bought it for small brush and it seems to do ok with it - but am I going to wreck the blade by using it on brush ? I have no idea how old the scythe is but my best guess is 20 or 30 years old. Any thoughts most appreciated.