Crack in top of my DG250M!

drolling

I was a bit surprised to note thata crack's developed in my Gitane - Running parallel to and just below the high 'E' string, it appears to start at the corner of the fretboard & travels about 3/4", ending at the rosetta inlays encircling the petite bouche.

Given this is an overbuilt, plastic-dipped hunk of plywood, I'm hoping that the crack is just in the finish. The top of the guitar's spruce, BTW, but I've no idea whether it's solid or a laminate.

Is there a simple way to determine whether this crack goes all the way into the spruce? Is this something that should (could) be fixed?

The cosmetic aspect doesn't concern me in the slightest, but I'd probably consider having it repaired if there's a chance it will spread and widen ~ or split in two when I'm playing one night!

I would really appreciate any advice you may have for me, thanks

Pugs47

I'm going from memory as I had a crack on a relatively new and quite exspensive archtop about fifteen years ago (luckily,mine was a finish crack);
Take a magnifying glass and then a light source to the left or right of the crack.......move the light source...if its a crack in the finish, the line of the crack or shadow will move with the light under the magnifying glass. If its in the wood, no movement. My recollection could be quite questionable so maybe one of the many luthiers on the forum will respond.

Jazzaferri

If the finish is really clear a very bright light and 10x magnification will tell the tale as well.

Michael Bauer

Get it to a competent repairman and get it stableized and then keep it properly humidified.

Otherwise, I wouldn't worry too much. GJ guitars are prone to cracking. Just think of it as opening up the sound... 8) . I have a Favino with 16 cracks in the top, and you'd be hard pressed to find a better sounding one anywhere.

Guys with newer guitars tend to have heart attacks about cracks. i used to as well. But as I've gotten intetested in vintage stuff, I have slowly learned not to worry too much about them. That doesn't mean that you shouldn't take every precaution to prevent them, and proper humidification is the single most important thing you must provide a guitar, but if you do get a crack, unless it's structural, you need not worry about it too much. Its' there now. Learn to love it.

frater

Exactly the same thing happened with my 250M. Have the crack fixed by a repairman as Michael said: it won't hurt the sound in no way. I don't know why but the 250M is very,very sensible to change of humidity. As soon as you feel the strings a bit flat on the fretboard and/or the frets a bit out-sticking. get your trusty Dampit and set things straight!

drolling

Thank you very much gentlemen!

The light's terrible here & I don't own a magnifying glass, so I still can't tell with my failing naked eye how deep it goes..

I can feel it with my fingernail, which is probably NOT a good sign, as one side's obviously slightly higher than the other.

It's not a place where I would have expected to see a crack appear, and tho' I know nothing about luthery & less about physics, seems to me that this would indicate some kind of tension/stress between the fretboard/neck and the body top.

More likely the top and a panel of wood glued to the underside that's the exact width of the fretboard, extending to the lip of the soundhole - The 'crack' seems to follow the edge of this panel exactly.

Not much, if any, arch to the top of this guitar, but gluing a wooden plate to the underside seems like asking for trouble. I hope that "good" gypsy jazz guitars aren't built this way!

Shmockiebaby

I have a 250M for about 2 1/2 years ow. I bought it at a discount, because it has about a 6 inch crack left of the low E, from the sound hole to the bridge. The crack was repaired professionally, is very tight and almost invisible, and got me a real big discount (the guitar was otherwise new). The guitar sounded, and sounds great,nso I took the chance. That crack has never moved since I've had it.

Now this guitar gets played more than any other guitar I have. It is about 5 feet away as I write this, and it is left out in my living room 80% of the time. I have a full house humidifier, in my main HVAC, and controlled by my programmable thermostat. Right now, in February, it shows 51%. I can pet my dog in winter, and no one gets shocked.

Long lead in to my actual point - in the last few weeks, I have two new cracks, from the fretboard extension to the rosette, on both sides of the fretboard. Treble side can be felt with fingernail on outer and inner sides of top. Bass crack can only be felt on outside of top.

So I think the woods and the finish must all still be shrinking, even in a very stable environment. Remember, my old, large crack is stable and almost invisible. But these two have occurred recently. I think there must be some stresses built into the guitar. Ebony doesn't shrink that much, so it must be the top. Probably leaving the factory too wet.

All if that said, I love the tone and playability of the guitar. 2.5mm +/- at 12 fret, .010s, loud enough to compete with a good dreadnaught, and feels like playing a Tele with .010s.

Bob Holo

That particular place on guitars is problematic because it's under a great deal of stress from the strings and it is where the largest longitudinal (along the grain) area of dissimilar woods are joined... dissimilar in... well... a whole lot of ways. A high density, high specific heat, anti-hygroscopic and relatively isotropic fingerboard mates with a low density low specific heat, extremely hygroscopic and anisotropic soundboard. So basically it's a natural cleavage plane under a lot of pressure and to make matters worse, the two conjoined materials react differently to nearly any physical stimulus. (or at the very least react similarly but at drastically different rates) Heat/Cold/Dryness/Humidity/Shock/Vibration... it's a real nightmare of a spot on (any) guitar. Even if a guitar is made perfectly - this area can cause you problems seemingly without cause or notice.

Anyway - that aside, you should definitely get those repaired. Your stable crack is nothing more than a PITA, because it's on a relatively low-stress area and it occurs between two large braces... which sort of function as natural cleats. (I mean, it's good that you fixed it as cracks can travel under cleats if they have a large open area that can receive shocks and move the wood etc..)

But you definitely want to get the ones along side the fingerboard repaired. Those are the most dangerous cracks on a guitar. Those are the ones that can make the neck just decide to come forward and the next thing you know, your guitar looks like a folding chair getting put away after a church banquet. Not to scare you, but... loosen the strings and go get it fixed ASAP because the only thing keeping your guitar from folding up right now, is the joint between the soundboard and the premiere barre. It's a strong joint, but was never meant to take that kind of stress, so eventually it will give and....