Slims Tips: "I often get asked what tunings I use for slide playing".....
"The most common one I use is a OPEN D tuning and goes from bottom to top as DADF#AD. It's great for those country blues songs and gives you more flexibility at the higher end of the fret board than it's close cousin OPEN G. Elmore James version of Dust My Broom is a prime example of OPEN D tuning at it's blusiest best. OPEN G tuning though is a real gem for getting that Delta Blues sound and has a bottom bass string that's made to boogie. It goes DGDGBD and was a favourite of John Lee Hooker, listen to "Boogie Chillun" or Son House's "Death Letter" to hear its growling power. Some people like Keith Richards remove the bass D so they can play a loose groove without thinking about dampening the strings but I'd advise to keep it on, hammer off the 3rd fret and then hit the open 5th string and you'll never want to go back to standard (European) tuning. Open tunings offer you instant freedom from normal rules and my main advise is to just experiment with them, if it sounds right then it is right! Look for patterns and try out simple two fingered shapes (double stops) whilst hitting the open bass note and see where it leads and don't forget to use a capo for key variations".