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Why not ? What could go wrong ?
I took a Fender Starcaster acoustic and added eight strings.



Sound sample and slide show of modification process.

what could go wrong...? if the top wasn't braced for those extra 8 strings, i am surprised you were able to even get them to tension.....

Yep, and with a tailpiece type bridge like that, the downforce is actually going right onto the X brace where it's trying to pull up from the bridge torque... so you could probably shave the X even lighter than you could without the harp strings That's something I've been wanting to try myself, actually.

Now drill a couple big holes through the sides and run a broomstick through the box with some bass strings on it

Interesting.

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PMoMC

....Africanized stings, or regular?

Well I am no expert, but the top area is well braced and I added a patch underneath the top bridge. It has lasted a week...we will see how much longer it lasts. I am even contemplating adding the other side (bass strings) to a guitar like this. First I will add some carbon fiber bracing though. I did have some tuning instability on the harp strings, but it is settling down now. I hope I can blame it on new strings and not winding the pegs very well (it was my first time). This sure is fun to play. I am getting better at pinless bridges too.

I am really starting to appreciate dowels. I made generous use of them, thinking, if the glue ever fails, they will be my backup. Plus it makes it so easy to get good pressure while gluing when otherwise gluing the bottom would have required a scissor jack or something.

At first I did not have the bottom bridge, and the sound was really weak. Adding the bottom bridge connected the strings to the vibrating region of the top and much improved the sound. But I have seen harp guitars (Pikasso) that only connect near the edge of the top.

I only have one shot of the bottom braces gluing up in the video, but they wrap around the bottom, and connect to the back with glue and dowels. That 'bottomstock' isn't going anywhere. I really overbuilt it as I do with all of my guitars. I need to improve on that.

Wild! Very interesting, way to go.

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Jim Watts
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Good for you Lactose. Why the heck not. Not a lot to loose but lots to gain.

i would expect the (6 string course)action to rise as the top is pulled into a concave shape by the "harp" array....when you say "adding bracing", how will you do that to a closed guitar...? i know very little about acoustic guitars

Brilliant, I think!

You know, from the pictures I have seen of harp guitar internals, I usually don't see a lot of extra bracing. Maybe they leave the top thicker. In some cases I have seen a zig zag (what is the proper term ?) carbon fiber brace arrangement in the bass side arm. So perhaps you don't need as much as you think.

My idea for adding a bass side harp arm or neck is:
-drill a hole in the side, on the bass side near where the neck attaches
-insert a carbon fiber spar (hopefully I can find one long enough) that plugs into a wood block at the bottom
-slide into position a wood block inside the body where the hole was drilled to hold the other end of the spar
-the hole will be covered

I am thinking this would help the body resist the tension from the 5-7 bass strings. Feel free to correct my novice thinking.
If you have a little bit of woodworking skill, this is a neat way to see if you would like a harp guitar without spending $2-20k.

Cool

Cool!
The only thing I would change is maybe trim those long strings hanging in the air.

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wah
Wah-wah-wah-wah
Wah

Hmm...cool? Sounds like an asian instrument
I agree with the idea of having nothing to lose with modding a starcaster

That's possibly a plywood guitar made in Indonesia or something... I've tried to break them intentionally without success... the top is so strong they can actually do without bracing at all! You could probably put 8 long scale bass strings on it and the guitar will still hold.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

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