Join Date: Nov 2016
Location: New Brunswick, Canada
I've always used spot putty to fill in small scratches and imperfections after sanding the bondo. Saves mixing up more just for a small fill. I've never used it alone so I'm not sure if it would work on something that big or not. Since it doesn't use a hardener like bondo I don't know if it would be strong enough to use alone. Hinson is right, try to get as much of the dent out as possible, then make sure you clean up ALL the rust and apply bondo in thin layers.
2007 Vulcan Nomad
2000 V Star 1100 Classic (Sold)
All stock except for:
Switchblade Quick Release Windshield
Ugly but somewhat functional saddlebags