Summary

This is a more elaborate (perhaps too much so) version of Makefast's TuneFast harp.

Key features of this remix:

Reinforcement struts to help prevent bending under string tension
Hollow body with resonant cone and F style sound holes
Same hardware as original
More ergonomic shape
No supports required

Note that the resonant cone tends to sound "better" when covered with the palm of your hand when playing. At least IMHO :)

Print Settings

Printer:

Ultibots D300vs

                                            <p class="detail-setting rafts"><strong>Rafts: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting supports"><strong>Supports: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting resolution"><strong>Resolution: </strong>                     <div><p>.2mm </p></div></p>                                                                                <p class="detail-setting infill"><strong>Infill: </strong>                     <div><p>25%</p></div></p>                                                        <br>                        <p class="detail-setting notes"><strong>Notes: </strong>                    </p><div><p>Note that for best results, you should print the struts in the same orientation as the STL file presents them, and use AT LEAST 1.2mm worth of shell/perimeter.  PLA makes a great  filament for making the struts, as it's stiffness works better than other "stronger" materials.</p><p>I also really liked the look of using "concentric" fill for the surface parts, which is supported in Slic3r.  Don't know if that's available in other slicers.</p></div>

Post-Printing

            <p class="detail-caption"><strong>Here's how the struts (in blue) are installed in the body.  </strong></p>                <div><p>You'll want to do a bit of sanding to make sure that the body halves mate well.  Having gaps between them will result in a "buzzing" sound when playing :(</p><p>Refer to the original at <a rel="nofollow" href="/thing:2709667">https://www.thingiverse.com/thing:2709667</a> for the excellent hardware assembly and tuning instructions provided there.</p></div>

How I Designed This

So I really spent way too much time running the original harp over and over in my head and came up with all sorts of way too impractical ideas to "improve" it. Instead of following through with most of them I just went ahead and did the most I could think of without requiring any new hardware or printing with supports.

Tunefast Harp with cone