William, Great idea. Do you have any photos you can share of one of your boards?
Possum Boards Revisited
I put three feet (They're small dowel caps from Hobby Lobby) on the backs of my dulcimers, then I put three fittings on the possum board with sockets in them that match up to the feet on the dulcimer.This allows me a positive hardwood-to-hardwood contact between the instrument and board with no actual contact to the instrument back. Also, with the feet sitting in sockets, the instrument does not slide around on the board.
The downside to this approach is that, since my dulcimers are different shapes and sizes, each has to have its own board. I make my own boards in a backyard workshop, though, so they're cheap.
I'm not familiar with a wood having the common name of Sweetwood. Sweetgum, yes, but not Sweetwood. What other names does it go by?
Dulcimer on a table - whether 5/8" or 3" thick -- is better than dulcimer on the lap. The lap is soft and absorbs sound. Tables are hard and reflect sound making the dulcimer louder. However. Dulcimer suspended even 1/8" above a "table" gives you even more volume because it frees up the entire back of the instrument so it can vibrate.
You can test this by setting two pencils on your table and putting the dulcimer on top of them.
Personally I like dulcimers with built-in feet, like my John Knopf Uncle Ed replica. You can make simple feet about 1/4" square that will stick on with double-sided tape. For my possum boards I prefer 3/8" or 1/2" thicknes and 1/4" suspension height. I have one board that is 1/2" Balsa -- verrrrryyyy lightweight!
When your friend makes your possum boards tell him not to put any padding on the suspension parts - whether they are just simple cross bars or fitted yokes or whatever. You want the dulcimer to directly touch the wood of the supports, for maxium amplification. Any padding, such as felt, will 'cost' you some enhancement. Wood to wood contact between the suspension bits and the dulcimer will not harm the dulcimer if the other wood is sanded very smooth and finished with ureathane or whatever.
I picked up some nice hardwood planks at an estate sale for a song (no pun intended), just the right size for possum boards. I’ve got some Sweetwood (native to NC) and some pretty, but unidentified hardwood. I gave some to my dear friend Maureen whose husband has been enticed into making us possum boards. I gave him a half dozen pieces of planks, and he is off, researching, and designing my friend and me a board. The planks I provided him are 3/8” thick, because I read in my research on possum boards that this was a pretty good thickness for a possum board, and they happened to be cut that way.
Meanwhile, I started playing around with some of the other planks that happen to be 5/8” thick, and have discovered that they provide a much richer sound. I’m talking about a plain plank of wood, no supports, or elevation, just a dulci on a plank, Appalachia style.
I would appreciate hearing thoughts from some of you possum board users on your preference of board thickness, and support or no support, support height, etc.