Full string tension (without exploding, this time!) Success!
geteilt von: https://feddit.org/post/36651939
So, I had kind of a mishap a few weeks ago: the original bridge of my Vihuela de Mano ripped clean off when I tried to bring the strings to tension. Might be that the glue surface was too cold or the natural oil in the rosewood prevented a proper bond. Or the glue surface was simply too small for 42kg of string tension.
After some consideration, I decided to redesign the bridge to be more of a lute style (with 3x the glue surface of the original bridge), while trying to preserve the original look. It's now made of cherry, with ebony and ivory inlays.
5 replies
Looks amazing!
Bummer about the old bridge. Indian rosewood is usually a pretty safe go to.
I’ve got some theories as to why it may have let go, but I have some questions first:
•what kind of glue did you use? •did you cut into the finish before gluing or just glue directly on top? •how did you go about prepping the mating surface on the bridge? •how did you clamp the bridge during glue up?
It is a beautiful piece and I especially love the rosette work. Great work.
Thanks! I used traditional hide glue, which I prepared in an electric glue pot. The top was unvarnished spruce, I did no surface preparation beyond basic cleaning. I used two c-clamps, mounted through the soundhole. Maybe I should have preheated the surfaces, my workshop is unheated and it was fairly cold that day.
Hide glue can be tricky to get just right. The bridge on my first guitar started lifting after a few months thanks to old hide glue. If you’re going to use it, I’ve found it’s best to make it fresh at time of use and don’t reuse old stuff that’s been sitting around for a few days.
It could also be that you needed to spread your clamping forces out more evenly. I use cauls that span the entire bridge and wings, but are slightly undersized to allow for cleanup.
Additionally, I find that on oily woods like rosewood you may need to rough up the glue surface with low grit sandpaper to achieve better mechanical adhesion as the oils may prevent glue from fully penetrating.
Regardless, when do we get to hear a demonstration? 😉
When the fret gut arrives, I didn't order the right sizes. 🙃 At the moment I only have four frets. Maybe I can improvise with some old strings...
Old school. Very cool.
Alternatively, you could keep it fretless and invent a new genre of funk 😜