antekboodzik
Oud Junkie
Posts: 109
Registered: 5-24-2010
Location: north poland
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Loose bar and top bulging
What a mishap... Only for a short time I enjoyed the sound of my second instrument (really, really nice). A few days ago, doing some minor peg
adjustments, I managed to let the lute "roll" from its back on the desktop, and the top has hit a corner of a small, plastic toolbox (fortunately
rounded, not sharp). Now, when pressing with finger in the area showed on the icture, there it can be feel that the top gives way a little and bends,
and probably the harmonic bar (roughly marked) must be loose as in can be hear like sound if its end "scraping" the top rib......... It is not a
problem when playing, but I started to observe, that the top has "bulged" a little in the area near rosette, and it reduces the clearance between
strings and the top to around 4mm. It is just in the place where fingers pluck strings, and it feels uncomfortable.
What to do? Open the body near the area of loose bar and try to to glue it back, as showed here:
http://lute.net/fixit/fixit2.htm
? Or maybe remove entire top and glue all braces again? May it be that they were too delicate (3,5mm thick, 15mm tall)? Would it be possible to fe-fit
the top back to the body? I am worry that after opening the top will no longer "fit" to the bowl, being somewhere too short...
Please, help 
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jdowning
Oud Junkie
Posts: 3485
Registered: 8-2-2006
Location: Ontario, Canada
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The braces are not too delicate at 3.5 mm wide.
Hot hide glue is strong but it is also brittle and a joint might separate if subject to an impact loading. Check if there is more than one brace
affected.
I would try a localised repair as shown in lute.netfixit. If that doesn't solve the problem satisfactorily then removal of the sound board would be
necessary. This might be easier than you imagine if part of the problem is that your glue was originally applied too diluted and so lacking in
strength.
You should not have a problem with refitting the sound board after removal - just repeat the gluing procedure that you used when originally gluing the
sound board to bowl.
You will need a thin artists (or kitchen) spatula to open the joint and to later work the hot glue into the joint as well as a hot iron to remelt the
glue as necessary.
Removal of lute sound boards for repair of loose braces was once a common maintenance procedure in the damp living conditions of the 17th C.
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antekboodzik
Oud Junkie
Posts: 109
Registered: 5-24-2010
Location: north poland
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Fixed... At least, microsurgery of the instrument went fine, and there is moderate improvement to the playability.
I managed to fix loose brace, as showed at the website previously linked. I couldn't say, if there were more loose braces, but after careful
examination nothing seemed suspicious. Also, I have plunged old string holes with toothpicks and re-drilled them, just because I could do this. Now
the 'plucking' action above soundboard and 2-3 cm under the rosette is about 4,5 mm for the first course, and 6mm under last one. It is still pretty
low, but acceptable for me. The lute remains stable after a few days. There is also a possibility to raise action at the bridge even more by 'sliding'
a thin sliver under string knots at the bridge.
I don't know what I did wrong. Was the damage so severe? When assembling the body, I remembered to 'dish' top ribs to make the belly slightly concave
around rosette, but it seems I was too shy with that? The concavity appears only near the edges, the middle part is flat, and the rosette even still
slightly bulged (but it doesn't interfere with plucking strings). Also, there is a small 'cant' along the grain just under the first course... Did I
glued one bar upside-down by mistake, or what? Ot it is loose in the middle?
However, the action at 9th fret for first course is perfectly around 2.7 - 2.8mm, and the lute sounds quite well and loud, especially in the treble
range
Some more issues:
- when removing soundboard, it must be 'undercut' from braces (and braces left glued to sides of the top ribs), or removed with all the braces at
all? So how bar ends are freed? If not loose, they hold the top from being 'wedged' from top ribs and itself,
- I am not sure, if there's better idea to 'ream' old string holes and plunge with toothpicks at all the lehgnt along (not partially from both
sides)?
[file]35262[/file] [file]35264[/file] [file]35266[/file] [file]35268[/file] [file]35270[/file] [file]35272[/file]
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jdowning
Oud Junkie
Posts: 3485
Registered: 8-2-2006
Location: Ontario, Canada
Member Is Offline
Mood: No Mood
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Thomas Mace in his 'Musick's Monument' of 1676 gives detailed instructions on how to remove and replace the sound board of a lute (the same method
also applies to an oud). Attached is the section referring to sound board removal. The whole text of the book may be downloaded free of charge - just
do a Google search.
The book is written and printed in 17th C English so may be a bit difficult to completely understand in all of its detail (even for native English
speakers who are not historians or luthiers!). Note that what appears to be an 'f' (without the cross bar) in the print should be read as an
(elongated) 's' except when followed by a 't' or a 'u'. So, for example, words that appear to read as 'difh', 'ufe', 'fquare' or 'firft' should be
read as 'dish', 'use', 'square' or 'first' whereas, for example, 'lowest' or 'suppled' are read as printed
However, in essence, Mace stresses the importance of moisture and heat to first soften the glued joints after which the joints may be gently easily
separated with a thin bladed knife. Mace uses a red hot iron to heat the moistened glued joints but cautions against the iron coming into direct
contact with the wood of the lute - for obvious reasons!
As for un-gluing the ends of the braces Mace writes that - after the glue has been softened - when you feel a brace (with your knife), then get your
knife under the brace and so gently force it (upwards) until you feel that it is loose. Then proceed this way - working from brace to brace - until
the whole sound board may be readily removed.
The 'Lace' referred to by Mace is a narrow cloth strip of linen or silk glued over and around the edge of a sound board to strengthen the joint -
found on 17th C lutes. This has to be removed in order to access the sound board/bowl joint.
[file]35274[/file] [file]35276[/file]
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