Crack In Top

[Dan Morris]

Any advice on how to handle a indentation/crack on a spruce top? The crack is about 2 inches long and it was caused when I was tapping in the rosette. I probably didn't have good enough support on the back side when I was tapping it in. The crack is along the outside of the rosette on the bottom of the sound hole and will be covered by the pick guard when that is put on. It's not visually noticeable from the top, although you can feel the rosette is a little low at that point if you rub it with your finger. It's not severe, but you can see it on the bottom side of the top. I don't think this would be a high stress point on the top. Is it best to just leave alone or should I try to pop it back in place? Does some glue along the crack make any sense? Thanks. Dan

Best if you post a photo.

[Dan Morris]

The amount of the "raise" on the bottom side of the top, from the crack is 1 or maybe 2 recipe cards. You can't see through the crack or anything like that. It is tight. I'm attaching a picture.

[tippie53]

that is not good , you can try working some glue into the crack and clamp it flat. If it doesn't close you may need to replace the top. On your rosette what kind was it? I make my rosettes so I can fit them by hand , you should be about .005 to .010 larger in the rout so the glue can flow. Once you get this glued you can place the sound hole supports. That should help to stabilize the area. I would not recommend anything but a wood glue. CA may stain the top. Tite bond should be fine.
Making it too tight is not good. Also be sure there is never anything under the top. I won't tap it in I will tap it into the glue later so make it so you can hand press it in.

Here is what I learned when things are too tight ,
A the rosette won't bottom out and you can sand through or make it so thin the rosette will ripple.
B if you make it too tight you can blow out the separators or not get the rosette to set in , pieces will shear or roll
C glue can't get into the rosette and it will lift.
D if it is a wood rosette I will use a heavy weight while glue is setting.
Post pics of the rosette.

[Dan Morris]

John, The rosette consists of plastic strips. This is a Martin dreadnaught kit. Here's picture of the rosette. Thanks. Dan

[tippie53]

you should not have to tap these. I use a plastic block and rub them into the channel.You know it is in when you see the glue oozing out of the plastic.
I use duco cement or weldon

send a pic after you glue this up and see what it looks like. That will tell you if you need to replace the top or not.

[Dan Morris]

I watered down some Tite bond and applied it to the crack/raise and worked it in as best I could, but the crack was real tight. Then I clamped it. The top had a piece of plywood between the clamp & top, so my clamp wouldn't dent the top. I placed a popsicle stick along the ridge, so the clamp would force that part down. There was wax paper between the bottom side of the top and the popsicle stick, so I wouldn't glue the stick to my top. That seemed to do the trick. I can feel a slight raise when I rub it, but it is less than the thickness of an index card. It is visible to the eye, but it is on the underside of the top, so it won't be seen. The sound hole brace will be placed across the crack, which should strengthen it. Based on what I'm seeing, I plan to go forward with this top. We'll see if it causes any issues down the road.