Mike's Oud Forums

Crack on the soundboard

Marina - 11-4-2010 at 03:04 AM

Hi there great oud builders!

I think that this topic was already on the forum, but I did not get it.

I have a problem with my new Mustafa oud (he build the soundboard). I am very pleased with the oud that I bought just a couple of weeks ago in Istanbul - but after a week in Israel, probably due to the weather, the soundboard cracke, and gooosh, it has A HUGE CRACK along the conection between "bookmatch".

Here is an ilustration, i took a photo from the forum and drowe the crack with red color.

How can I fix it?

Thank you so much!



oud3-1.jpg - 43kB

katakofka - 11-4-2010 at 03:22 AM

Hi Marina
take it back to Mustafa. The rosette needs to be removed glue the crack from inside. Meanwhile keep the Oud in high humidity conditions ( get a humidifier and keep the Oud at 45-50% humidity). The crack will disappear in high humidity conditions and reappear whenever the Oud is in dry weather conditions.

Marina - 11-4-2010 at 03:29 AM

Hi Katakufta!
Thanks.

I can not take it back to Mustafa - I will be in Turkey maybe next year for my vacations! ;-)
But I got your point - get the humifider.
I am afraid that the cracks are too big 2 disappear...

What do u think about some kind of "wooden mud", I don't know axactly how it is called, but it fills the cracks at wooden objects?


SamirCanada - 11-4-2010 at 03:32 AM

NO! dont put anything like that in there.

I would wait and take it back to him. Although its hard to tell how he will fix it.

katakofka - 11-4-2010 at 03:34 AM

I would take it to a known luthier in Israel in this case
he or she should remove the rosette, glue it from inside (yes, by filling the gap with glue and wood in such a way that the filling will be the same as the colour of the faceboard).
Don't do it from outside or let anyone do it from outside.

katakofka - 11-4-2010 at 03:45 AM

there is a choice to do Marina regarding if the Oud will stay in dry conditions or not
if this is the case, the Oud will be kept in dry conditions, let the crack to be open fully and filled from inside. After that the Oud should stay always in dry condition (30-40% humidity). Alternatively, the gad is closed naturally by high humidity condition and glued without adding any material to fill the gap. In this case, the Oud should be kept in high humidity conditions (50-60%).
Depending where the Oud will stay you decide between these 2 methods

Marina - 11-4-2010 at 03:54 AM

Usually, the weather here is very humid - goosh!!! like monsoon season - just last couple of days :mad: the weather changed...
GOOOOSH!
Humidity:14%

It is usually 50% - 85%

I newer needed humifider.

:mad:

katakofka - 11-4-2010 at 04:14 AM

14 %? oups....my lungs will shrink at 14% not only a Oud faceboard:)
so let the luthier making it closing naturally (he put a wet sheet of paper on the top, this will close the gap naturally by humidity) then glue it from inside. And keep the Oud in high humidity always

Marina - 11-5-2010 at 01:34 AM

I put my oud in hard case, took wet (not soooo wet, almost dry) cloth and put it on soundboard, left the oud in the case overnight. The idea come from wet sheet of paper (katakofka). The cracks amost dessapear! (well I keep the oud the case now.)
I mean huge cracks, like 1mm or even more! So for little cracks it would work very good.
I just newer had old dry oud in such weather conditions. Creapy....

When the Mr.Hide comes again, I'll be ready.
Thanks all!

Dr. Oud - 11-5-2010 at 08:42 PM

The center seam of the 2-piece face has opened as the wood dries and shrinks. This is very common, and has many causes, but not to worry. The sound will be affected as the sound wave is not produced by the whole face vibrating, but rather each half separately. The repair is simple and does not require removing anything or filling from the inside. If the crack is less than 1/2 mm , it can be filled with hide glue alone. No wood filler, no synthetic glue, please. If the opening is 1/2 mm or larger, a sliver of matching wood (probably spruce, or maybe cedar, so ask Mustafa what he used to be sure) can be fitted from the outside. Do not dampen the face because you are only making the wood swell by adding moisture, which will only close the opening temporarily anyway. Moisture is not good for the face, as it always should be kept dry. Using a humidifier is a good idea, but it may not close the opening.

Marina - 11-6-2010 at 03:21 AM

Thanks!
:wavey:

katakofka - 11-6-2010 at 07:05 AM

Quote: Originally posted by Dr. Oud  

...If the opening is 1/2 mm or larger, a sliver of matching wood (probably spruce, or maybe cedar, so ask Mustafa what he used to be sure) can be fitted from the outside.


Doc, if the gap is filled with matching wood what will happen if the OUd stays in high humidity conditions as it's the case in the region where Marina lives? the filling with high humidity will be rejected as the wood is expanding...no?

Dr. Oud - 11-6-2010 at 03:48 PM

Quote: Originally posted by katakofka  
Doc, if the gap is filled with matching wood what will happen if the OUd stays in high humidity conditions as it's the case in the region where Marina lives? the filling with high humidity will be rejected as the wood is expanding...no?


No. I've never seen wood expand enough to reject a filler due to humidity variations, particularly the soft wood used for soundboards. Soundboards often shrink during the first few years anyway because the wood is such low density, especially if they were constructed during a wet season or in a high humidity region or with unseasoned wood. Over time, it will shrink until it stabilizes in its home environment. If the wood was aged before construction, it is less likely to open seams and cracks as it shrinks. As the wood ages, variations in humidity will have a lesser effect. I would fill it during a dry season so that the cracks will stay closed all year.

myeyes2020 - 11-6-2010 at 07:09 PM

Hi Dr Oud,

What's your opinion about filling the crack (or any soundboard crack) with collagen? Thanks,

Adel

Help in Israel

Yaron Naor - 11-7-2010 at 12:21 AM

Hi Marina,
Thanks for shearing with this issue
and thanks for everyone for the good replys

I live and work in Israel and I can help you with pleasure.

If you want to contact me, call 0547655797

Thanks
Yaron Naor

Will Varnish wiil avoid the problem?

omazuz - 11-7-2010 at 12:54 AM

Marina- i hope your oud will get better....
And i was wondering if Varnish on Top will avoid the problem and the top will not crack ?

jdowning - 11-7-2010 at 05:17 AM

The sound board should not be varnished (presumably, as a Turkish style oud, the top has not been varnished or had any kind of finish applied by the maker). In any case, sealing only the outside face of the sound board will not prevent the wood absorbing atmospheric moisture because the inside surfaces would remain unsealed.

Richard has summarised the correct repair procedure for fine cracks (using hide glue a.k.a. collagen) or by using thin splints of matching wood for wider cracks.
Some luthiers prepare wider cracks using a thin, wedge shaped, cutting tool (that can be made from a needle file of the correct section) in order to straighten any irregularities in the crack making it easier to fit the filler strips and produce an almost invisible repair.
This work is relatively straightforward but should, nevertheless, be undertaken by an experienced luthier. Yaron has offered to assist.

Dr. Oud - 11-7-2010 at 08:04 AM

Quote: Originally posted by myeyes2020  
Hi Dr Oud,

What's your opinion about filling the crack (or any soundboard crack) with collagen? Thanks,

Adel

I believe collagen is used to smooth wrinkles in the human face, not cracks in an oud face.
You know where collagen comes from, don't you? Your own butt! :D

myeyes2020 - 11-8-2010 at 06:36 PM

Richard et al,

Thanks for your reply! So let me get this straight. Collagen (not aka hide glue) should not be used to fill cracks in an oud?
Excuse me for making this question a big deal but I kinda feel like a "butt" for trusting a friend. You see, in the biggest winter of the history of our state last year, I stayed at my sister's house and the power went out at my apartment (no heat or humidifier) and my favorite oud's sound board got a long crack. Upon putting it back in higher humidity and or putting a damp paper towel on the sound board, the 2mm crack completely disapeared. this gave me the impression that I could put a slither of some type of glue in the crack and have it close and with a nice smoothe apearance.

I didn't want to do this myself. Upon the advice of and "experienced" oud fixer who had a "secret" method for repaiting such cracks, I trusted the oud to this person to fix the oud and he didnt want to reveal the "secret method." To my shock, when I recieve the oud back in one week, the crack that was filled with collagen looked hideous. When I mentioned this to the fixer, this person said that before filling with collagen, the advise of THREE other reputable luthiers was that the best course of action for this oud was to put collagen.

Furthurmore, this person claimed to have REMOVED the rosette, cleaned the the lose debri of dried hide glue inside the oud and now the oud sounds "30%" better.

When I said that this crack looked "sh##ty, I was told that I was crazy to have such a conclusion and that this appearance will go away as the oud ages and becomes more aged looking.
Now that the oud has been exposed to normal summer humidity, the crack which seemed to close in on itself created a long bump (like a speed bump).

So am I wrong to believe that I was conned and that it is a bunch of BS that three reputable luthiers would highly recommend that a 2 mm crack be filled with collagen?

Adel

jdowning - 11-9-2010 at 05:26 AM

The word "collagen" means "glue producer" derived from the Greek word for glue 'kolla'.
Hide glue (aka 'collagen' because it consists mainly of that group of animal protein) is made from animal hide and sinews comprising of up to 35% of collagen protein and is the oldest glue in the world having been around for over 8,000 years.
It is still the best glue to use for instrument construction and repair as it is strong, hard (does not yield under stress like some modern synthetic adhesives such as PVA) and is reversible.

If the crack in your sound board was 2 mm wide under normal ambient conditions (about 50% Relative Humidity) then the usual repair procedure would be to fill the gap with a sliver of matching wood.

fernandraynaud - 11-9-2010 at 04:38 PM

Every time I read about les craques, I pity my poor clavichord, with a crack on the soundboard. Doing such a repair with the strings in place is very hard. Access from below is blocked unless i remove all the keylevers. And something about unstringing and then re-stringing about 60 double courses, then weaving the felt listing (that mutes the strings at rest) through the strings, just makes me put the little piece of spruce and the scalpel back in the "someday" parts box. It sounds pretty good as it is, the crack doesn't fully cleave the soundboard, the bridge holds it together, a lot of clavichords have cracks, it gives it "character" -- all the usual excuses. Ouds are so easy.

jdowning - 11-10-2010 at 05:23 AM

fernandraynaud's clavichord experience begs the question "does a sound board crack adversely affect an instrument's acoustic response?"
In the course of maintaining and repairing 19th C pianos I found many with sound board cracks that did not appear to affect the acoustic performance. Indeed, the general consensus in the piano industry seems to be that these cracks are nothing to be concerned about and certainly not worth the considerable expense involved in their repair.

So, has anyone carried out 'before and after' trials on an oud to find out if a sound board crack does affect acoustic performance (verified by improved response after a crack has been repaired)?
Is a crack repair purely cosmetic?