www.KitGuitarsForum.com

I have built this crossover guitar. It sat in the house for 4 weeks while we were in India. When we left a month ago the humidity in the house was probably around 4o to 45%. It is now around 55%.

The top is fan braced (9) but has no bridge patch. I'm pretty sure the top was okay when we first got home a week ago. The guitar was out until last Tuesday when my wife put it in a case. I took it out yesterday to set the bridge location, and I found the top caved in as in the picture I've drawn. It is still domed on the edges, but down the middle it has sunk in, probably around 1/8". My first thought was, this thing has dried out, but then the humidity is higher then when I built the guitar, so does that mean that this action of the top is due to too HIGH a humidity? I don't know which direction to go with it so for those of you guys who can tell me what is going on I'd sure appreciate the help. Thanks.



Kevin

I had trouble opening the picture. Without the bridge there is almost no lateral bracing in the lower bout. I know many build classical guitars with no dome, yet when strung up the string tension still creates a dome. I am wonder if you go ahead and place the bridge ( an additional pretty stiff lateral brace) and string it up the guitar will be fine. The bridge and the tension will pull the top up.

you should be fine 10% is not horrible. once the bridge plate is set and string tension I would expect it to be fine.

Thanks guys, it is encouraging to hear your responses. I kind of panicked. The only thing that made sense to me was higher humidity has caused this so I will go with that and see if I can restore it and then store it in the case and see if I can dehumidify it some.
I am pretty sure that I will French polish this guitar.
I thought about the fact that the bridge needs to be on there to support that top in this area. If I glue the bridge on now will I have difficulty getting the shellac finish nice and level around the bridge? Anyone done it this way?

Easier to FP with the bridge off. I have done both ways.

I blew some warm air into the guitar and the top came back up about 50% so it is moving in the right direction. I'll get some desiccant to put in the case to hopefully continue to restore to dome to the top. I may go ahead and glue the bridge on too to help hold the top shape.