FWIW: When I first picked up my safety razors they were fairly dirty. I soaked them in water with Borax and Grease Lightning (multi-purpose cleaner) and with a little toothbrushing I was able to quickly clean them up and get them looking great. On the one I've settled into using the most I just blast it with hot water while shaving to rinse out soap scum and whiskers, and leave it at that. After the shave I open it up and set it out to dry. If it ever builds up with scum I'll probably just wipe it with a towel...break out the toothbrush only if needed.
Peace,