I use this resin for most of my repairs due to its fast acting cure time. I usually sand the area first to prep the damaged area and again once it has hardened. I take this on all my surf trips and quick repairs .
This stuff is really easy to use, and actually comes out looking surprisingly good on most dings repairs. As long as you have good direct sunlight it doesn't take long for it to harden and cure. Even with cloud cover it will still work but it takes twice as long if not longer.
I have found that sanding down the area lightly helps to make for a lasting repair. After squeezing the resin in the ding, you can place some boxing tape on top and push it down flat to get a nice flush repair. Once its fully cured, the tape peels right off. Must have a tube handy for any surf trip.
I have a mixed quiver and Dura Resin works on all of my boards epoxy or poly, the tube stays fresh even in my hot car for the past 3 months of summer!