Mandocello conversion ?

[Jazz Ad]

I've been looking for an el cheapo mandocello for a while.
I don't plan to make it a concert instrument, just looking for something playable and decent sounding.
Being a bassist and mandolinist, I figure a mando would be nice around campfires.
Unfortunately, either these instruments cost and arm and leg, or they're downright crappy (Soares'y).

So I was thinking, what about converting a gipsy/jazz style guitar into a mando ?
These guitars are available anywhere at low prices.
They have pretty much the same scale, 26" or so. Adapting the tailpiece and headstock to accomodate 8 strings, change nut, a good setup and I could be done. My only concern would be additional tension from having 8 heavier strings. The top may not like it. I guess as long as I have a trussrod, I shall be fine.
What do you think ?

 

[AndyPanda]

I'm looking into the same sort of project - was looking for info and came across your 9 year old post. A little late for a reply but .......
D'addario has a page that lets you experiment with different string gauges and scale length and pitches to calculate tension --- it's very cool. I was able to create a mandocello string set that puts the exact same tension on the guitar as a six string set. I mean in the calculator I was able to create the set - I haven't actually converted my guitar yet - still deciding if I'm going to be able to manage the 7 fret reaches on a 25" scale instrument. I was planning on using a flat top with bridge pins - but it would certainly be more authentic to start with a gypsy jazz guitar with tailpiece and floating bridge. And a lot easier to intonate with the floating bridge -- the extra heavy bass strings will have me needing to modify my bridge with more angle to the saddle I fear.

This is an example of a set I built on the D'addario website - total tension is about the same as a medium guitar set. For comparison - the prepackaged mandocello set that D'addario sells uses 22 34 48 74 I built my custom set trying to keep the tension balanced and total tension equal to a Medium guitar set.