There was a post not so long ago about a kydex sheath damaging the Res C on a SOD handle....there are some tips I posted in that which might help...the main one I have benefited from is to line the sheath with the rubber from an inner tube from a bike tyre...dirt can still get in...but can be washed out...I mainly do it to protect a sharp edge from rolling if you are running with the knife on your belt... as opposed to the asthetics side of things...but I don't like to see scratches either. In an emergency the inner tube rubber makes great tinder as well...easily lighted when wet.

Here is a link to that thread

http://www.scrapyardknives.com/ubbthread...true#Post228558