I added a much heavier rubber cutting edge to my 6 1/2' Curtis blade. I originally had it sticking about 5". The rubber rolled back almost 45 degrees. I then changed the mounting so that rubber stuck out about 2". By mounting the rubber in front of the steel cutting edge. I'm happy with this setup. /forums/images/graemlins/smile.gif
Here is a link to the thread with pictures that TresCrows started on his plastic edge. Click Here
2019 Rural King RK55HC with Loader & Backhoe; 2001 New Holland TC40D with Loader
I find that the rubber edge sticking out 2" from the backing plate is good. Any more than that and it will roll/bend under pressure. I was worried that it would wear down fast, but there is very little wear after a full season of plowing a couple paved and several gravel drives.
Mark