I agree with the others -- a Hughes Church Dulcimer kit.  The second dulcimer I built 40 years ago. 

Replacing the Nut & Bridge should be straightforward as long as they aren't glued.  If the Nut is glued, try heating it up with a heat gun or hair dryer on High for 10 minutes or so.  That softens Titebond and Elmers glues.  If all else fails you can cut them off and sand them down flat before making new ones from some of the scrap maple from your recent build, to sit on top.  

As mentioned, the tuners could use at least a good cleaning.  They weren't all that great of quality back in the day though...  If they are, as I suspect, 3 tuners on a bar, you can get a replacement pair for about $10 from Stew Mac (I just checked the price).

I agree, John. Looks like a Hughes Church dulcimer. If it came in to my shop I would recommend a new nut and bridge.

Ken

"The dulcimer sins a sweet song."

I agree. The string spacing looks really odd and arbitrary. I would suggest a new nut and bridge as well.

I would guess that it's an assembled church dulcimer kit from Hughes Dulcimer Company out of Denver.  These were made of luan plywood ("Philippine mahogany"), and were of simple design.  If you remade the nut and bridge, you could get the 3 courses of two strings that we're talking about.

Here are a couple of pictures.  THere are no markings inside to indicate maker and such.

dulcimer.jpg  •  96KB

dulcimer close up.jpg  •  83KB

@John-C-Knopf is correct.  A six-string dulcimer is just tuned as a three-string dulcimer with each string doubled.  So if it's a standard size, DD-AA-AA or DD-AA-dd would work.

Of course, just because a dulcimer can take up to six strings doesn't mean you have to use them.  I have a six-string dulcimer but sometimes only put on three strings.

Photos!!  As John sez, 6-stringers are usually 3 couplets rather than 6 equidistant.  Is there a maker's label inside?   

I wonder if it's an old six-string kit that someone lost the instructions to, so they set it up like a guitar....

That seems unusual for a dulcimer.  Usually if a dulcimer has six strings, they are arranged in 3 pairs on the fretboard.  Each string pair (or "course") have a distance of about 1/8" between them, so they can be played as one string.

Tuning is generally in the DAA or CGG range (Ionian or Major mode) if it's a conventional length dulcimer.  Each pair is tuned alike.  Do you have any photos of it?

A friend of my daughter has a old, very rustic 6 string dulcimer - she wondered if it's tunable and playable.  I'm a bit of a novice with the variations of dulcimers, so don't know if this is odd or not.  It has six strings, all equally spaced, like a guitar.  Is that type of string arrangement common?  To what notes should such an instrument be tuned?