spruce top with wavy surface, is it a problem?

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Nikos_Greek
Posts: 34
Joined: Thu Jun 22, 2017 9:18 am

spruce top with wavy surface, is it a problem?

Post by Nikos_Greek » Fri Nov 10, 2017 9:32 pm

Hello everybody!

I have a question for the luthiers in this forum. At the beginning of September I got a new guitar (Spruce top, Indian Rosewood back and sides) from Antonio Raya Pardo, an exquisite guitar of great craftmanship. I have posted some photos at another post but I don't think they will be of any help.
I have kept the guitar in it's hard case with a humidifier (room humidity around 60%, steady temperature 20-22 C) away from any heat source whatsoever. I hadn't played the guitar for a week because I was away. When I returned last wseekend I noticed the spruce top below the bridge towards the rim (that is where the top and the side of the guitar meet) had somehow wrinkled, the Surface was no more flat but a bit wavy. the same Thing I notice on the opposite side, that is on the back side of the guitar in the middle and towards the rim (where the two parts of the back side join). The back side has a Kind of curve looking inwards. I do not notice any looseness in the Woods in the area, nor any problem with the glue. More importantly I don't notice any Change in sound. The guitar Plays beautifully exaclty like the first days. Now I don't Claim that both surfaces (top and back) were completely straight, but I have the impression that the wavy surface is now more noticeable. The question is is this common, I mean that the wood changes shape after the guitar is ready, no other factor being involved (misuse of the guitar, extreme conditions). Will the guitar develop any structural problem in the future? I also have a Paulino Bernabe M 50 which has a kind of inward curve just before the bridge, below the strings, but she had that thing from day 1. Again no problem with sound, playability or anything else. Communication with Mr Raya is a bit difficult since he doesn't speak English (through Google translator). Any advice from an expert here would be precious to me.
Thanks a lot for your understanding,
Nikos

Nikos_Greek
Posts: 34
Joined: Thu Jun 22, 2017 9:18 am

Re: spruce top with wavy surface, is it a problem?

Post by Nikos_Greek » Fri Nov 10, 2017 9:37 pm

I forgot to say, the guitar is very light and it came to me with Daddario hard Tension strings. Could the strings have effected the curvature on the top and back?

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dta721
Posts: 55
Joined: Wed Aug 23, 2017 6:59 pm
Location: Ottawa, Canada

Re: spruce top with wavy surface, is it a problem?

Post by dta721 » Sat Nov 11, 2017 3:10 am

Nikos_Greek wrote:
Fri Nov 10, 2017 9:32 pm
.... Communication with Mr Raya is a bit difficult since he doesn't speak English (through Google translator)...
Nikos
Can you take a few digital photos to show the issues then send by email to him? A picture is worth a thousand words so that he can appreciate your concerns? His email response can then be translated much easier for you to understand?

Btw, I do have the D'Addario Pro Arte Hard Tension EJ46 on my humble guitar, would not think this would create such problem.

My 2 cents!
:)

Nikos_Greek
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Joined: Thu Jun 22, 2017 9:18 am

Re: spruce top with wavy surface, is it a problem?

Post by Nikos_Greek » Sat Nov 11, 2017 8:56 am

I have a Reply from Mr Raya, he believes it might be the humidity Level (60% in my place, 25-30% in Granada in summer). He might be right because I had additionally put a humidifier in the case, now I have already removed it;dta 721 you are right I will also send photos.

simonm
Amateur luthier
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Joined: Sat Jun 27, 2009 10:22 am
Location: Germany, Würzburg.

Re: spruce top with wavy surface, is it a problem?

Post by simonm » Sat Nov 11, 2017 10:26 am

Nikos_Greek wrote:
Fri Nov 10, 2017 9:32 pm
... When I returned last weekend I noticed the spruce top below the bridge towards the rim (that is where the top and the side of the guitar meet) had somehow wrinkled, ...
Without seeing it, it is difficult to be sure. However, I think what you are seeing is "imprinting". This means that with a very thin top you can see the outline of the fan struts on the surface. If this is what it is you will be able to count the fans which are likely symmetrical and you will see a deliberate pattern.

This is quite common on lightly constructed guitars and in general does not cause any problem. It can be hard to photograph but you can feel the "humps" with the tip of your finger and see them at certain light angles.

Do you know anyone near you who also has a lightly build luthier guitar? If so have a long and you may find that their guitar is the same. Sometimes you can feel it with your fingertips although it is difficult to see. Some construction methods are likely to make it more obvious that others due to different amounts of pressure being used to glue the struts in place.

Nikos_Greek
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Joined: Thu Jun 22, 2017 9:18 am

Re: spruce top with wavy surface, is it a problem?

Post by Nikos_Greek » Sat Nov 11, 2017 3:49 pm

I am able now to upload some photos
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albert-canuck
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Joined: Wed Sep 20, 2017 2:13 am
Location: Fisher Branch, Manitoba

Re: spruce top with wavy surface, is it a problem?

Post by albert-canuck » Sat Nov 11, 2017 3:56 pm

Beautiful guitar.

I notice this a bit with my 1968 Taurus M-56 guitar just above the saddle as a slight dip. I have replaced the extra high tension strings it had with high tension as a precaution It is also apparent on my new to me 1979 Ramirez 1a 10 string guitar but not on my Bernabe M50.

When I first got the 1a the wavyness was quite noticeable both visually and by feel as three bumps behind the saddle, though not quite as deep as it appears in your photos. A few weeks later this non flatness has almost disappeared. The humidity in my house is 45% +- 5% throughout the year and I have them out of their cases on a diy guitar stand. I believe it is the humidity that the guitars were adjusting to and considering they are 40+ years old I don't think it will become a problem. Perhaps if there was a crack in the top before hand it may become a problem but probably not for a non damaged top. Your top may also be thinner than what is on my guitars. But it makes me nervous too.
1979 Ramirez 1a 10 String
1992 Paulino Berbabe M50
1968 Taurus model 56
2005 Dan Lankford 8 Course Renaissance Lute
old German Lute Guitar
1982 Yamaha G231 II (first guitar)

astro64
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Joined: Sat Aug 06, 2016 7:43 pm
Location: American Southwest

Re: spruce top with wavy surface, is it a problem?

Post by astro64 » Sat Nov 11, 2017 5:58 pm

Looks indeed like imprinting. Too high humidity could also be a factor if the wood expands too much it will expand. You might see this on the back as it expands outward leaving a depression around the center connecting strip. The luthier may be right. If your room is at 60% do NOT put a separate humidifier in the case. Imprinting of the braces is nothing to worry about. Many good guitars show that, especially spruce tops since the tops tend to be thinner than solid cedar tops. But too high humidity is not a good thing, nor is too low of course.

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