Bridge rotation too high... countermeasures?

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JurgenV
Myrtle
Posts: 74
Joined: Mon Dec 10, 2018 6:58 am
Location: Bavaria, Germany

Bridge rotation too high... countermeasures?

Post by JurgenV » Sat Nov 14, 2020 7:29 pm

Hi
I´m back again with a problem on one of my falcate braced OOO. After the two OOO I built to compare x-bracing to falcate bracing using the principles of Trevors book I built a quite nice rosewood OOO with the bolt on bolt off neck. Setup was done had it again testplayed by the usual guys and everything was fine. Then I put it in its case for around 2 month. When I took it out again today I wondered why it felt so strange playing it... and realized the action was now incredibly high: around 5mm.
Neck relief is still the same as before but the bridge rotation is now visibly higher than with all the other two falcate OOO I still have here. Another thing is that the top of this guitar shows kind of an imprint of the bracing: when I look at a very low angle past the top I can see where the bracing is. I don´t have that with the other falcates.

I´m not sure what to do. I did use a bridge with a slightly smaller footprint so I could try a bridge with more surface area (shouldn´t change the resonance frequencies too much as I needed to use two brass pins to adjust the top resonance). Or I can try to change the neck angle, or both. Any suggestions? Every piece of advise is appreciated.
I would really like to avoid to rip the top and start all over again. I like the top and the sound of the guitar...

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Trevor Gore
Blackwood
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Re: Bridge rotation too high... countermeasures?

Post by Trevor Gore » Sat Nov 21, 2020 10:42 am

It doesn't look like anyone else has had this problem, Jurgen. I haven't. My ~15 year old prototypes are still all fine. It sounds like an assembly issue, though hard to figure what went wrong.

johnparchem
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Re: Bridge rotation too high... countermeasures?

Post by johnparchem » Sat Nov 21, 2020 11:19 am

On some of my classical with tops close to 2 mm I can see the the main falcate braces through the top. I have not had over rotation of bridge, except one time I found the bridge was lifting off the top on the trailing edge.

JurgenV
Myrtle
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Joined: Mon Dec 10, 2018 6:58 am
Location: Bavaria, Germany

Re: Bridge rotation too high... countermeasures?

Post by JurgenV » Sat Nov 21, 2020 6:44 pm

Thanks for the replies. I actually did both things lowering the saddle and changing the neck angle. Action is down to around 2.8mm. As I´m not in a hurry (there are no customers in sight) I will just wait and check from time to time if there are further changes.
And if .... retopping is still a possibility

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