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 Post subject: Ovation Top Crack Advice
PostPosted: Tue Feb 21, 2017 11:56 pm 
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First name: Murray
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Hi,

I have an Ovation I'm fixing for a friend of a friend. It was seriously dried out when I got my hands on it, which certainly caused the crack. I've been introducing moisture and the crack is closing and will be ready to be sealed pretty soon. The crack runs from the end block to under the bridge.

Here's where it gets tricky - Ovations are fan braced and the crack is under a brace that runs down the center seam of the top. I can't cleat it because there's already a brace there. Any suggestions on how to seal this? Glue? Tight bond, CA and LMI instrument glue are available. My current plan is to wick a bit of water in with a small paint brush and introduced some water thinned glue at that time. I'm open to other ideas though!

Thanks,
Murray


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PostPosted: Wed Feb 22, 2017 12:00 am 
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Here's a shot of the crack before I started humidifying.


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PostPosted: Wed Feb 22, 2017 6:33 am 
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Old Growth Brazilian Rosewood
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My condolences.... Many shops won't work on Ov*tions because they are a huge can of worms in terms of lousy construction, lots of use of ep*xy, etc. and a penchant for developing permanent dimensional instability in what little wood they have....

Nonetheless you're being a good guy and helping someone out and that always motivates me to help too! ;)

Notice how thick the finish is........? Have a little guitar with your finish eh... :)

One of the Luthiers at Elderly instruments developed a technique for difficult cracks that either won't close or if we can force them closed we are likely to cause additional cracks somewhere else. We've used this technique a number of times with great success AND only when appropriate for the instrument. It's not something that I would do with a valuable or vintage valuable instrument but with an Ov*tion and when no one's looking it just might help get you and your friend of a friend where you want to go.

Cleat the crack open instead of attempting to close it. Something in the order of back joint reinforcement spanning the crack with appropriate grain direction is how we cleat the crack for this method. You will see why in a minute. You are also creating a "floor" for glue application.

I heard you about the fan braces, yet another reason why many shops won't work on Ov*tions in so much as traditional techniques don't apply well with these.

Once you figure out how to cleat the crack open with a full length cross crack strip and integrate it to the existing fan brace(s) you are ready to seal the crack.

You can mix up some quality structural ep*xy such as West Systems, System III, or even Bob Smith but use long open time of at least an hour mix the epoxy and yes you can color it with trans tint dye.

With nitrile gloves on and some ventilation apply the color matched ep*xy to the crack and smooth it all out. Use only water to clean, carefully.... ep*xy off areas where you don't want it.

Let cure a couple of days and then level sand and buff, bill the client, next....:)

As mentioned this is not a method for a 1936 Martin OO-18 or any other decent instrument but for an Ov*tion who cares..... This is the "appropriate for the instrument" thing.

Be advised that this kind of crack is often also a tell tale of other RH related issues, lifting bridge, etc. And Ov*tions are not immune from needing neck resets as well.

As such if there is no way out of this one.....:) and you have to fix the thing this method would work fine for what you have.

Consider the idea as well that we could force this crack closed but in my experience if once rehumidified the crack will not stay closed on it's own at 45% RH you will likely develop more cracks as a result of adding stresses from closing this one. That's when filling is advisable over closing.

Hope this helps.


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PostPosted: Wed Feb 22, 2017 11:14 am 
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Or you could just casually drop an anvil on it.

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These users thanked the author Chris Pile for the post: Hesh (Wed Feb 22, 2017 7:13 pm)
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PostPosted: Wed Feb 22, 2017 1:37 pm 
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Brazilian Rosewood
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Yikes! That's a pretty big crack.

Have you inspected the fan brace directly under it? If it didn't let go- I would think it would be mostly split in half lengthwise.

That doesn't look like the sort of crack that will close back down with a little more humidity ... Probably going to need splinting. Or Hesh's Epoxy fill ;)



These users thanked the author truckjohn for the post: Hesh (Wed Feb 22, 2017 7:14 pm)
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PostPosted: Wed Feb 22, 2017 1:52 pm 
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Remove the center fan.
Put a new one in spanning the crack as per Hesh.
Filler up w/Epoxy.



These users thanked the author david farmer for the post: Hesh (Wed Feb 22, 2017 7:14 pm)
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PostPosted: Wed Feb 22, 2017 7:14 pm 
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Old Growth Brazilian Rosewood
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Chris Pile wrote:
Or you could just casually drop an anvil on it.


laughing6-hehe :D


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PostPosted: Wed Feb 22, 2017 7:26 pm 
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I knew Hesh would like that.

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These users thanked the author Chris Pile for the post: Hesh (Thu Feb 23, 2017 5:30 am)
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PostPosted: Wed Feb 22, 2017 7:37 pm 
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Hands up, those who, in a blind sound test, can tell an Ovation from a Martin from a Taylor from a Gibson from an etc. Just as I thought.

Sent from my SM-T350 using Tapatalk

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PostPosted: Thu Feb 23, 2017 12:45 am 
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Pretty sure I can tell the Ovation will sound the worst, but that's not the point of this thread. It's about how to fix the crack in the top. I hate 'em, but if the guy brought it in.... I'd try to fix the thing.... even though I'd rather use the anvil on it.

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These users thanked the author Chris Pile for the post: Hesh (Thu Feb 23, 2017 5:30 am)
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PostPosted: Thu Feb 23, 2017 5:37 am 
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Old Growth Brazilian Rosewood
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WilbPorter wrote:
Hands up, those who, in a blind sound test, can tell an Ovation from a Martin from a Taylor from a Gibson from an etc. Just as I thought.

Sent from my SM-T350 using Tapatalk


I'm with Chris and I could tell, that's easy. What's more difficult to tell is the difference between stainless frets and NS on an electric ax, I failed that test. :? :D

7 pounds of ep*xy has a specific tone to it from an audiophile point of view. Thick finish has a "clicky", crappy tone too. Know this is subjective but after a while you know what to expect from different makers and "dipped in finish" instruments.


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