Dark spot in new guitar -- Should I be concerned?

[just_guitar]

Hi all,

I recently purchased a Gibson J-45 that sounds incredible; however, upon inspection, I found that there is a dark spot on the underside of the soundboard by (and on) a brace. I don't think it's mold; rather, it seems like during the finish spraying process, some of the spray got inside the guitar. It doesn't feel moist at all. What do you guys think?

https://photos.app.goo.gl/Zt22xuN2jPLKs2nc6

[JDaniel]

Interesting, but finishing overspray might not be what this is. Spray is unlikely to get inside and if it did the spray pattern would be different than this. Based on your picture, I wouldn't worry in the least if it were mine.

[just_guitar]

If not finish overspray or mold, then what could it be? It doesn't look like mold, does it?

[Shuksan]

I'm betting that it's overspray. Does your J-45 top have a sunburst? If so, I think that's why it's visible. Take a look at this Gibson acoustic guitar factory tour video to see how they spray the sunburst starting around 2:30 into the video. You can see that there is some sort of insert in the sound hole to prevent finish from getting on the inside of the back. It's shaped like a circular well. I bet it doesn't seal completely against the underside of the top. As you can see in the video, when he is applying the sunburst, he sometimes sprays at a pretty low angle around the sound hole. If that insert doesn't fit snug against the underside of the top, then some of that dark finish for the sunburst could get past the insert. You can also see that the color of the insert changes from orange at the start to brown by the end so a fair amount of finish gets shot inside.

https://www.youtube.com/watch?v=-bVa_H7j1Fk

[bsman]

I would have a needle biopsy done to ensure it isn’t malignant...

[redir]

Looks like over spray to me too. Like Shuksan said if it's a burst top then that's probably your 'problem.'

[just_guitar]

Thanks, everyone! Looks like I shouldn't be worried, then.

[runamuck]

I agree with the others and think you shouldn't be worried about this at all.

[mirwa]

Something is wrong if your looking inside your guitar with a mirror.

It’s as if your looking for problems?

Steve

[just_guitar]

It's my first purchase of any single item remotely that expensive (new, so $2400), so I wanted to make sure that nothing dangerous (like mold, water damage...) was affecting it. Wouldn't want to find out too late. Based on the responses here and my own inspection, though, it seems fine.

[B. Howard]

That is buffing compound that was thrown off the wheel by the edge of the sound hole.

[just_guitar]

Thanks for the insight! ... So it should be fine, right?

[JDaniel]

Originally Posted by just_guitar

Thanks for the insight! ... So it should be fine, right?

Yes, Brian diagnosed it. Just a little schmutz. Time to enjoy that J-45 now.

[Quickstep192]

Originally Posted by B. Howard

That is buffing compound that was thrown off the wheel by the edge of the sound hole.

I'm impressed by this diagnosis! Clearly the voice of experience! Cool...