Fixing Guitar Dents - Luthier Tips du Jour Mailbag
In this episode, luthier Robbie O’Brien shows a tip to fix small soundboard dents.
Video Transcription
[on-screen text reads: Luthier Tips du Jour Mailbag]
Mailbag question: Is there a way to repair small dents in a soundboard?
Robert O'Brien: Today's Tips du Jour Mailbag question comes to us all the way from Brazil. "Robert, is there a way to repair the small dents in a soundboard? Thanks for your response, Miguel in Brazil."
Miguel, a great example of that would be fingernail marks for classical players in the soundboard down below the first string around the soundhole area and the rosette area. Yeah, there's a way to fix that. I have a video out there that shows using CA glue for that.
Now, one of the problems with CA glue is that you put it on there, it dries very hard. You have to scrape it back. If you don't get it extremely level, you'll have a small little hump and you'll see that if you look across the top of the finish. It's wavy.
Also, another risk is that when scraping that you go through the finish. Now, most guitars that we're going to do this repair on the tops have become darker over time due to exposure to ultraviolet light. And if you scrape through that finish into the fresh wood, then you're going to have a blotchy or a lighter colored area.
So recently I started using a product called Aqua Coat. This is a pore filler. It's a water-based pore filler. It works great for that. However, I've also discovered that it works great for filling small imperfections in soundboards like dings from fingernails around the soundhole area or the rosette area.
Since it's water-based, it's very easy to apply. It dries quickly. You can level it and it's very, very easy to do that rather than having to scrape it back. So let me show you how I do it.
How I fix small imperfections
So Miguel, here's the guitar in question. This one actually had the in-case humidifier come loose during transit and bounced around the top a little bit. Due to the limitations of technology here, I don't know how well this is going to show up, but there's some very small dings in the top there, and the owner just decided he couldn't live with that. So we're going to fix it for him.
So I'm going to start just by lightly sanding this area with some 320-grit paper. I'm then going to take a little dab of Aqua Coat and put it on a hard rubber pad here, like a squeegee and just work it into the low areas and it doesn't take very much at all. Excess can go back into the jar. There we go. Now I'm going to let that sit for a few minutes, sand it again lightly, and start the finish repair. That's all there is to it.
So here I'm lightly sanding. I'm now up to 600-grit, lightly sanding the area that I leveled with the Aqua Coat. And depending on how pronounced those dents or dings are, you may need multiple coats of the Aqua Coat. It looks like I'm going to be able to get by with just one light coat, and now I can start my finish work.
So after a little bit of work on the French polish finish here, this is going to be as good as new and nobody will even know that there were a few minor dents in that top.
[on-screen text reads: More Luthier Tips and online courses available at www.obrienguitars.com. Private and small group guitar building and finishing instruction available.]
