Subject: Archlute Bridge

From: sterling price <[email-masked]>
Date: Thu, 14 Jun 2012 21:27:19 -0700 (PDT)

Hi-I'm not sure if this list is still active so here goes---I have a
   small archlute with a bridge that is made of ebony and I would like to
   replace it with something more appropriate. Also because the string
   spacing and action is all wrong. My question is--what is involved in
   removing a bridge and replacing it without removing the soundboard? I
   just need some advice on how to proceed, or if I should leave it alone.

   --Sterling

   --

---

From: Richard Lees <[email-masked]>
Date: Thu, 14 Jun 2012 23:03:37 -0700

Hello Sterling!!

Its been a long time posting for me, I have been pretty busy with work...
I offer what I have done in the past.
Many of the EXCELLENT builders who post here will no doubt have 
wonderful input to give you , no doubt..

For my part, having replaced a number of bridges in restoration work  as 
well as gluing on bridges in  new construction,  I would say
It is much better to remove the top. MUCH BETTER in fact
Your description is good by the way, and certainly justifies replacing 
the bridge.
Also since the current bridge is not to be kept, you do have a great 
advantage here.
However there are issues .
Removing a well glued on bridge is no easy task. Heat and moisture are 
required and the application of these forces can easily damage a top 
beyond repair...
After you remove the top from the bowl , you must focus the heat and 
moisture very carefully, and take extreme caution not to be impatient 
and lift up the bridge with any force as this could create tear outs in 
the top underneath. This situation is a nightmare to deal with , but CAN 
be addressed if the damage is shallow.
Given that you are going to make a new bridge, I suggest that you  begin 
by removing whatever top detail has been placed on the top of the old 
bridge ( if any) and then to CAREFULLY plane down the old bridge with a 
block plane to where the remaining bridge is perhaps 1.5 mills thick or 
less  if you can ...
Now you can place hot water on a rag cut to fit EXACTLY on top of the 
remaining bridge with a LITTLE overlap  and then cover the cloth with 
tin foil or saran wrap to prevent the water from evaporating.  Please 
leave this in place for a while .
As  thin as the remainder of the bridge now is, the water and heat 
should penetrate fairly well into the top and glue joint underneath, and 
begin to loosen the bond.
Now under one of the ears see if you can't slip a single edged razor 
blade between the bottom of the bridge and the top... You must not force 
this .... if there is any resistance you should stop immediately!
You will need to apply more heat and moisture using hot water and a 
SMALL  iron directly on the top of the remainder of the bridge on the 
area where you wish to start, and try again... I stress that it is 
important to be careful to control how much heat and moisture is 
absorbed in the top and most importantly  to keep this in area as close 
to the perimeter of the bridge as possible..
If you have removed the top, of course you can apply moisture and heat 
from UNDERNEATH the top just below bridge, and be very effective as the 
top itself is more porous than the ebony.
Carefully move the razor blade along the joint until the bridge 
remainder lifts up completely along its length....

At this point I recommend damping the top at least around the area where 
there has been heat with cold water and prefer myself , to damp  the 
entire top - top and bottom to equalize the tensions so as to  to help 
avoid selective shrinking of the top and the ensuing warps that will 
incur as a result. If you do damp the entire top , AVOID the ROSE TOP 
AND BOTTOM !!!!!!!!!!!!!!!!

  Just after the top has been damped, I then place the top (topside down 
) in a go bar box ( you must  use some cellotape on the go bar box 
bottom where the bridge area is going to be , so that the remaining glue 
in the bridge area of the top doesn't bond it  to the box)  and then  
using cellotaped bars of your manufacture (say 1/2 x 1  x 12 inches or 
so) go bar clamp these bars down across where the bridge was located  to 
ensure that the top is flat in this critical area.  Also brace the 
existing lateral braces of the top by placing go bars in the center of 
each of these lateral braces and at each end , and put go bars on the J 
bar as well as the treble bars.... I recommend leaving it like this for 
several days until the top has stabilized, is flat,  and all moisture 
you have put into the top is gone.
Now comes an interesting thing......
The new bridge should actually be glued on with the top with the  same 
humidity  as when all the braces were glued down in the first place. 
This is to prevent stresses from being introduced into the top which 
will will deaden the sound.
Since we have most likely no record of what this humidity figure was , 
we now have a bit of a mystery !~!!!
In one lute I worked on and which needed a complete bridge re gluing -  
the bridge was lifting up under the ears and also under the first course 
but was otherwise perfect,  my client wanted to reuse the original bridge.
This instrument by the way  was made by a well known and well respected 
American luthier.
As such,  I faced this problem of not knowing the relative humidity used 
during the gluing of the braces
I discovered that keeping the top in a go bar box at 44 percent humidity 
to start with, the top developed a bow with the center of the top 
depressed relative to the edges, and this within less than 20 minutes 
from removing the go bars, and this in a room with a relative humidity 
of around 55 percent! This indicates to me that the top was in fact 
braced at a higher humidity.
  I slowly raised the humidity in the box 5 percent at a time,  with a 
good deal of time used  to stabilize the top at each setting and this  
over the next week or two.
I discovered that only around 55 to 60 percent humidity in the go bar 
box,  did the top hold its flatness fairly well after removal ......  
WEIRD!!!!!
I later learned from one of our best lute players here on the west coast 
that this particular builder (who he knew)  built his instruments in a 
dampish basement and didn't use a humidity controlled go bar box to 
brace his tops.......

Well anyway (and having no choice)  I glued the bridge back at 55% .
The instrument sounded great thereafter, our builder did do an admirable 
job.
This  hopefully will give you some idea at least of my process in this 
kind of repair...

best

Richard Lees

On 6/14/2012 9:27 PM, sterling price wrote:
> To get on or off this list see list information at
> http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
>

---

From: sterling price <[email-masked]>
Date: Fri, 15 Jun 2012 01:47:54 -0700 (PDT)

Richard--thanks very much---this is just the sort of info I was looking
   for.
   Taking a lute apart sort of scares me--the fear is I will just ruin
   it.  This lute has other issues--it came from England to very dry Utah
   18 years ago and the soundboard developed a split at the seam soon
   after it got here. Now the split goes almost the whole top but it has
   not hurt playability. Perhaps I should just make a new soundboard....
   I will keep you all posted on what I do.

   --Sterling
   From: Richard Lees <[email-masked]>
   To: sterling price <[email-masked]>;
   "[email-masked]" <[email-masked]>
   Sent: Friday, June 15, 2012 12:03 AM
   Subject: [LUTE-BUILDER] Re: Archlute Bridge
   Hello Sterling!!
   Its been a long time posting for me, I have been pretty busy with
   work...
   I offer what I have done in the past.
   Many of the EXCELLENT builders who post here will no doubt have
   wonderful input to give you , no doubt..
   For my part, having replaced a number of bridges in restoration work
   as well as gluing on bridges in  new construction,  I would say
   It is much better to remove the top. MUCH BETTER in fact
   Your description is good by the way, and certainly justifies replacing
   the bridge.
   Also since the current bridge is not to be kept, you do have a great
   advantage here.
   However there are issues .
   Removing a well glued on bridge is no easy task. Heat and moisture are
   required and the application of these forces can easily damage a top
   beyond repair...
   After you remove the top from the bowl , you must focus the heat and
   moisture very carefully, and take extreme caution not to be impatient
   and lift up the bridge with any force as this could create tear outs in
   the top underneath. This situation is a nightmare to deal with , but
   CAN be addressed if the damage is shallow.
   Given that you are going to make a new bridge, I suggest that you
   begin by removing whatever top detail has been placed on the top of the
   old bridge ( if any) and then to CAREFULLY plane down the old bridge
   with a block plane to where the remaining bridge is perhaps 1.5 mills
   thick or less  if you can ...
   Now you can place hot water on a rag cut to fit EXACTLY on top of the
   remaining bridge with a LITTLE overlap  and then cover the cloth with
   tin foil or saran wrap to prevent the water from evaporating.  Please
   leave this in place for a while .
   As  thin as the remainder of the bridge now is, the water and heat
   should penetrate fairly well into the top and glue joint underneath,
   and begin to loosen the bond.
   Now under one of the ears see if you can't slip a single edged razor
   blade between the bottom of the bridge and the top... You must not
   force this .... if there is any resistance you should stop immediately!
   You will need to apply more heat and moisture using hot water and a
   SMALL  iron directly on the top of the remainder of the bridge on the
   area where you wish to start, and try again... I stress that it is
   important to be careful to control how much heat and moisture is
   absorbed in the top and most importantly  to keep this in area as close
   to the perimeter of the bridge as possible..
   If you have removed the top, of course you can apply moisture and heat
   from UNDERNEATH the top just below bridge, and be very effective as the
   top itself is more porous than the ebony.
   Carefully move the razor blade along the joint until the bridge
   remainder lifts up completely along its length....
   At this point I recommend damping the top at least around the area
   where there has been heat with cold water and prefer myself , to damp
   the entire top - top and bottom to equalize the tensions so as to  to
   help avoid selective shrinking of the top and the ensuing warps that
   will incur as a result. If you do damp the entire top , AVOID the ROSE
   TOP AND BOTTOM !!!!!!!!!!!!!!!!
   Just after the top has been damped, I then place the top (topside down
   ) in a go bar box ( you must  use some cellotape on the go bar box
   bottom where the bridge area is going to be , so that the remaining
   glue in the bridge area of the top doesn't bond it  to the box)  and
   then  using cellotaped bars of your manufacture (say 1/2 x 1  x 12
   inches or so) go bar clamp these bars down across where the bridge was
   located  to ensure that the top is flat in this critical area.  Also
   brace the existing lateral braces of the top by placing go bars in the
   center of each of these lateral braces and at each end , and put go
   bars on the J bar as well as the treble bars.... I recommend leaving it
   like this for several days until the top has stabilized, is flat,  and
   all moisture you have put into the top is gone.
   Now comes an interesting thing......
   The new bridge should actually be glued on with the top with the  same
   humidity  as when all the braces were glued down in the first place.
   This is to prevent stresses from being introduced into the top which
   will will deaden the sound.
   Since we have most likely no record of what this humidity figure was ,
   we now have a bit of a mystery !~!!!
   In one lute I worked on and which needed a complete bridge re gluing -
   the bridge was lifting up under the ears and also under the first
   course but was otherwise perfect,  my client wanted to reuse the
   original bridge.
   This instrument by the way  was made by a well known and well respected
   American luthier.
   As such,  I faced this problem of not knowing the relative humidity
   used during the gluing of the braces
   I discovered that keeping the top in a go bar box at 44 percent
   humidity to start with, the top developed a bow with the center of the
   top depressed relative to the edges, and this within less than 20
   minutes from removing the go bars, and this in a room with a relative
   humidity of around 55 percent! This indicates to me that the top was in
   fact braced at a higher humidity.
   I slowly raised the humidity in the box 5 percent at a time,  with a
   good deal of time used  to stabilize the top at each setting and this
   over the next week or two.
   I discovered that only around 55 to 60 percent humidity in the go bar
   box,  did the top hold its flatness fairly well after removal ......
   WEIRD!!!!!
   I later learned from one of our best lute players here on the west
   coast that this particular builder (who he knew)  built his instruments
   in a dampish basement and didn't use a humidity controlled go bar box
   to brace his tops.......
   Well anyway (and having no choice)  I glued the bridge back at 55% .
   The instrument sounded great thereafter, our builder did do an
   admirable job.
   This  hopefully will give you some idea at least of my process in this
   kind of repair...
   best
   Richard Lees
   On 6/14/2012 9:27 PM, sterling price wrote:
   > [1]http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
   >

   --

References

   1. http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html

---

From: William Samson <[email-masked]>
Date: Fri, 15 Jun 2012 16:55:49 +0100 (BST)

I'll start the ball rolling - The critical thing is what kind of glue
   was used to attach it to the soundboard.  If it's synthetic, there's no
   easy way to get it off.
   If hide glue was used, alcohol can dissolve it, though you need to be
   careful because it can also ruin the finish of the instrument -
   particularly if it is French polished.
   For what it's worth, I'd do my best to preserve the original
   soundboard.  I believe that older wood is generally better than what we
   can get nowadays.  It IS possible to take off a soundboard, perform
   repairs, and put it back carefully without making too much of a mess of
   things.  Any signs of repair are, I believe, honourable features of a
   mature lute.  At least that's how the old ones liked them.
   Bill
     __________________________________________________________________

   From: sterling price <[email-masked]>
   To: "[email-masked]" <[email-masked]>
   Sent: Friday, 15 June 2012, 5:27
   Subject: [LUTE-BUILDER] Archlute Bridge
     Hi-I'm not sure if this list is still active so here goes---I have a
     small archlute with a bridge that is made of ebony and I would like
   to
     replace it with something more appropriate. Also because the string
     spacing and action is all wrong. My question is--what is involved in
     removing a bridge and replacing it without removing the soundboard? I
     just need some advice on how to proceed, or if I should leave it
   alone.
     --Sterling
     --
   To get on or off this list see list information at
   [1]http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html

   --

References

   1. http://www.cs.dartmouth.edu/%7Ewbc/lute-admin/index.html

---

From: "Ted Woodford" <[email-masked]>
Date: Fri, 15 Jun 2012 12:36:27 -0400

I'll add my two cents, though Richard provided a wealth of ideas. Planing 
down the existing bridge is an excellent tactic! I find aliphatic glues 
(white or yellow) actually easier to remove than hide glue. They often come 
loose without the addition of water. I put a several layers of aluminum foil 
over the top around the bridge for insulation when heating it. I use a 
regular household iron for that.

It's possible to glue on the replacement bridge using hot hide glue and a 
rubbed joint. I believe many Spanish guitar makes have used this method. It 
takes advantage of the glues' tendency to contract and pull things together 
as dries. Basically one slides the two parts back and forth a couple of 
times while the glue is hot, creating a suction not unlike what happens if 
you rub two microscope slides together. The repairperson then holds it 
firmly in place until the glue has gelled. It takes a couple of minutes.

If the seam is open it might be just as well to patch it with a spline of 
spruce while the bridge and strings are off. It's not likely to ever close 
by itself in the dry atmosphere of Utah! Richard's observations on humidity 
control are excellent. Fixing the open seam would seem prudent if you decide 
to separate the top from the bowl to apply clamps to the new bridge. There 
should be enough flex in the top that total separation from the bowl isn't 
strictly necessary. Freeing it up to the level of the third bar should leave 
an opening wide enough to get some lightweight deep throat clamps in there.

The main thing is to map out the geometry before starting. What angle does 
the neck take relative to the face under string tension? Is there an 
appreciable bulging behind the bridge that disappears when the strings are 
slackened? Pay close attention to the height of the string holes over the 
soundboard while it is strung to pitch and use them as a guide for 
calculation.
-Ted

---

From: Sterling <[email-masked]>
Date: Fri, 15 Jun 2012 20:51:38 -0600

Hi- from what you all are saying about this, it seems that it is probably beyond my abilities to attempt this. I would certainly learn a lot from the process but I really don't want to ruin this lute. I have already done a lot to it like converting it from twelve to fourteen courses(with octaves).
Might I ask if there is someone on this list who would be willing to do the bridge replacement on this lute? I could send it anywhere in the US...
Sterling

Sent from my iPhone

On Jun 15, 2012, at 10:36 AM, "Ted Woodford" <[email-masked]> wrote:

> I'll add my two cents, though Richard provided a wealth of ideas. Planing down the existing bridge is an excellent tactic! I find aliphatic glues (white or yellow) actually easier to remove than hide glue. They often come loose without the addition of water. I put a several layers of aluminum foil over the top around the bridge for insulation when heating it. I use a regular household iron for that.
> 
> It's possible to glue on the replacement bridge using hot hide glue and a rubbed joint. I believe many Spanish guitar makes have used this method. It takes advantage of the glues' tendency to contract and pull things together as dries. Basically one slides the two parts back and forth a couple of times while the glue is hot, creating a suction not unlike what happens if you rub two microscope slides together. The repairperson then holds it firmly in place until the glue has gelled. It takes a couple of minutes.
> 
> If the seam is open it might be just as well to patch it with a spline of spruce while the bridge and strings are off. It's not likely to ever close by itself in the dry atmosphere of Utah! Richard's observations on humidity control are excellent. Fixing the open seam would seem prudent if you decide to separate the top from the bowl to apply clamps to the new bridge. There should be enough flex in the top that total separation from the bowl isn't strictly necessary. Freeing it up to the level of the third bar should leave an opening wide enough to get some lightweight deep throat clamps in there.
> 
> The main thing is to map out the geometry before starting. What angle does the neck take relative to the face under string tension? Is there an appreciable bulging behind the bridge that disappears when the strings are slackened? Pay close attention to the height of the string holes over the soundboard while it is strung to pitch and use them as a guide for calculation.
> -Ted
> 
> ----- Original Message ----- From: "sterling price" <[email-masked]>

---

From: Chris Newman <[email-masked]>
Date: Sat, 16 Jun 2012 06:13:42 +0100

Question from a newbie with zero experience. Could one laboriously plane/ abrade the bridge off the soundboard? 
Chris

---

From: Jon Murphy <[email-masked]>
Date: Sun, 17 Jun 2012 02:53:42 -0400

Sterling,

I'm sort of a lurker on this list, I had started building a lute some 
years ago - after getting interested by making the Music Maker's flat 
back to see if I could handle the play. Medical matters have taken me 
away from the lute, but I retain interest. I still play, and sometimes 
repair, harps and other stringed instruments.

You say that the split in the soundboard doesn't affect the playability, 
but it could in the future if it widens. May I make some suggestions 
from one who deals with wood (I am a wood turner). And if my suggestions 
are totally out of line in dealing with a lute may I ask the more 
knowledgeable on this list to say so.

Removing the top and replacing it involves a certain amount of work and 
expertise. I make very thin hollow forms on my turning lathe, and as 
they are usually of relatively green wood they often split on the end 
grain. I rub sawdust into the split, then drip in thin CA glue. This 
effectively makes new wood as the sawdust and the CA glue meld (not 
really new wood, but better than glue alone). If you are thinking of 
removing the top/soundboard anyway, perhaps you should try this first.

As to the ebony bridge, someone suggested grinding it down rather than 
taking it off. That also sounds like a "good fix" to try. You could make 
a new bridge and glue it on top of the ground down ebony.

Let me stick my neck out now, in this community of luthiers. There are 
two basic forms of stringed instruments. The harp is one in that the 
strings pull directly on the "soundboard". The other form has the 
strings parallel to the soundboard, and pressing on it over a bridge. 
That form is separated into two sub-groups - the lyre, psaltery, cithera 
(zither) is one group and the violin, guitar, lute, etc. is the other. 
The former have a string for each note, and the latter have a neck and 
fretboard (whether fretted or not) that allows for fewer strings to make 
the notes.

These differences are important in the production of the sound. Musical 
sound involves the overtones of the plucked or bowed string (or for 
woodwinds and horns, the shape of the air column - but we are speaking 
of stringed instruments). I'll address the harp first. Contrary to the 
opinions of most of my harping friends (pun intended) the construction 
material of the harp body has little effect. The harp strings sing to 
the open air, and the fullness of sound comes from the direct vibrations 
that the soundboard, under tension, passes to the sympathetic strings. 
The harp body is not a resonating chamber, except to the extent that it 
enhances the vibrations in the soundboard that are passed to other 
strings. I.e., the soundboard is not a transmitter to the sound in the air.

Now to the bridged instruments. Here the resonating chamber of the body 
has more effect, and is more integrated into the sound transmission to 
the air. At the extreme we have the violin bridge, a complex shaping 
with cutouts so that the bridge itself affects the passing of the direct 
vibrations of the strings to the soundboard, and therefore the 
resonating chamber that is the body. At the other end we have psaltery, 
lyre, and zither  - where the body is not so resonant. A solid bridge, 
and a high tension, and less resonance.

In the middle is the lute group, the plucked instruments with a neck and 
fretting (in the sense of finger pressure on the string to change the 
note, not the actual frets). The entire combination of body and 
soundboard are a resonating chamber, but the bridge is a "passive" pass 
through (in contrast to the violin bridge). Where the violin is made as 
a body of the same material the lute group has a body and a soundboard 
of different material. The goal of the bridge is to pass the vibrations 
to the soundboard, but it is also needs to be of a harder wood to not 
wear away from the movement of the strings in tuning.

Perhaps the ebony is too hard, vibrations move at different speeds in 
different woods (or materials, depending on the density). But I wonder 
if there is any need to replace the ebony bridge with a more traditional 
material - it seems to me that it would make a good bridge. Perhaps the 
amplitude of the vibrations in the wood is reduced with the harder wood, 
perhaps there is a compromise that resists wear but also retains 
amplitude. That is pure speculation, but if I had my old shop and "silly 
scope" I could test it. That would be fun, one of the burdens of old age 
and a reduced space is the lack of tools.

OK, I've blessed/cursed you all with my ramblings. I'm very curious as 
to your reactions. In the harp world there is a continuing argument over 
the "solid" soundboard and the laminate - but it is a bit silly as the 
"solid" isn't solid. A harp requires that the "long grain" of the wood 
be across the soundboard, else the tension of the strings would 
immediately split it (the total tension on a medium sized Celtic harp is 
over a thousand pounds). To make a solid soundboard in one piece would 
require a tree of four feet diameter, so they take the solid pieces and 
put a backing on them - which is a laminate anyway. Which comes back to 
the split in the lute soundboard, and the "new wood" by gluing with 
sawdust. Doesn't seem to have affected the sound of "solid" soundboard 
harps.

One wants to maintain the integrity of the vibrations within the wood, 
and from one part of the body to another. Small variations won't be 
heard, it is the overall resonance that is important. I think it is 
important to understand where that resonance comes from in the various 
instruments - and they are not all the same. The final object it to put 
a sound in the air (neglecting amplification and pickups as that is 
another matter, and one I'm adamant on - music is changed as soon as it 
passes through any device, even if it is perfectly recorded it still 
depends on the ability of the speakers, and subtlety is lost). There is 
but one device that properly interprets the mixed vibrations that we 
call musical sound, and I'm in awe of it. The human ear can hear a mix 
of vibrations and separate them, and the auditory portion of the human 
brain can re-assemble them into the individual sounds. Think of it, you 
couldn't do that with the best of computers and Fourier analysis. You 
could break out the individual sine waves of the mixture, but you'd 
never know which came from the oboe or the flute. It is the re-assembly 
that is magnificent.

Best, Jon

On 6/15/2012 4:47 AM, sterling price wrote:
>     From: Richard Lees<[email-masked]>
>     To: sterling price<[email-masked]>;
>     "[email-masked]"<[email-masked]>

---

From: Richard Lees <[email-masked]>
Date: Sun, 17 Jun 2012 16:00:32 -0700

Hello Chris and Sterling et allus!

I have been off this thread as I have been out of town for the last 
several days...

To answer Chris's question, NO , one does not abrade/plane the bridge 
off the soundboard at all.

The problem we face is that wood is an excellent thermal sink, and as 
much vertical mass as a bridge has - being 5 to 7 mm high or thereabouts 
from treble to bass on a Baroque instrument-  its near impossible to wet 
and heat the bridge itself and have the heat and moisture  pass through 
the bridge onto the glue joint and loosen same.  You could be there 
applying heat and moisture for hours and the minute you remove the iron, 
the joint will immediately cool down and the bond will reset before you 
can separate the bridge from the top even a little bit !!!
In fact, in this scenario, the only workable solution I know if is that 
you must heat a sharpened oil painting palette knife (a REALLY THIN ONE! 
)  while trying to slip it under  a an ear seriously wetted  with hot 
water where you test to see if the joint is opening with a single edge 
razor blade, this in order to start the process.
  Then, if you are successful, and can gently slip the palette knife 
underneath the ear a little,  you add more hot water in front of the  
knife ( which you must continually reheat as you work) and as you  
gently push the knife down the length of the bridge you must wet and 
heat as you go.
... This is dangerous because the bridge being relatively thick will not 
give as the knife is passing underneath. The only thing than can "pull 
away" from the underneath of the bridge as the bond is hopefully 
loosened,  is the top itself.
  If the bond is even marginally holding as you are pushing the knife 
underneath it you  can very easily cause tearout of the moistened top as 
I indicated in my first email and believe me , you DON'T want this.
Also its hard to control the water and keep it confined to a small area.

If you want, therefore, to save the bridge you are currently removing, I 
believe you really have no choice but to remove the top completely so 
you can apply heat and moisture from the BOTTOM of the top directly 
under the bridge into the bond area. Here you have several things 
working for you.
Thing one :
The top should be around 1.75 to perhaps as much as 1.95 mills here,  
NOT 5 to 7 mills thick as is the bridge.
Thing two:
Here the top is MUCH more porous than the bridge and will absorb water 
much more freely into the wood so that  you can actually affect the bond 
directly.

NOW
  If you don't need to save the bridge then, it makes sense to plane it 
down.
This is done NOT TO REMOVE IT  , but to get it as THIN as possible.
In this way,  the heat and moisture will penetrate the remainder of the 
bridge successfully (now only about 1 mill or so thick)  and really  
loosen the bond .
Also, if the top is off, you can work it from both top AND bottom as 
well and be even more effective in loosening the bond with water and 
heat , and also keep the work area small.
Lastly, because  the bridge remainder is now very thin, it will also be 
flexible (especially being water soaked) and therefore will be much 
easier to lift off as the knife passes between it and the top,  and will 
lessen the chances of pulling up wood from the top .

---

From: Richard Lees <[email-masked]>
Date: Mon, 18 Jun 2012 19:12:02 -0700

As usual,
Dana Emery strikes again !

Excellent post .......
excellent post.......

Sonically too, Ebony is not the most musical of woods and while I have 
retopped a beautiful archlute for a player out here which had ebony 
staves, one could lightly sense the enharmonic character of ebony in its 
sound... now for bridges,  Dana is right with respect to correct build 
procedures ......But if our mystery bridge turns out to actually be 
ebony ( and I have seen some pretty strange stuff done in our modern era 
with lutes) now would be the best time to replace it
I especially like Dana's suggestion to check all joints !!!!!
In the retopping of the archlute I mentioned above MANY braces (well 
over half!) had crystalized glue joints and so I  had to re-brace the 
entire instrument..... This instrument which was made by a pretty well 
known luthier was built in the late 70s.
AND if the top is pushing 20 plus years , Dana's additional suggestion 
of simply putting on a new top is indeed called for...............
A last note to Dana's post....
some years ago i posted a quick observation on cracks, and its worth 
mentioning  it again.
And Dana is yet again right on target....
The Spanish masters of lutherie during the mid 60s  many of  whom I had 
the great honor to know , were absolutely firm on this issue.. We are to 
brace perhaps 5 or 6 percent LOW with respect to the expected humidity 
the instrument is going typically see.... This is to insure the health 
of the top and to make sure the top sounds well too.
BUT there is another monster lurking here......
If the players don't also agressively monitor EXCESSIVE HUMIDITY as when 
when the relative humidity is in excess of say 20  percent of the build 
target, then the wood will expand accordingly ... Now since the 
plantilla or shape of the instrument is fixed by the braces and bowl , 
the softer top, as it expands,  has no where to go...
What happens then is that the wood first bellies upwards and then starts 
to crush itself, under these high humidity conditions and then, when the 
humidity drops , the top can REALLY crack,  and whats worse, at a higher 
level of humidity even than the target build point!
This occurs because by virtue of have been laterally crushed, the top is 
fundamentally NARROWER than before. When the humidity drops and the top 
shrinks even further, these catastrophic failures can occur.
I restored several German harp guitars like this... The back of one of 
them, a Haberman instrument, had shrunk so badly that it lost over1/4 of 
an inch in width relative to plantilla so that when I removed the back 
you could hear the instrument groan as the stresses were relieved and 
the sides started to reconform .
If this is what has happened to Sterling's lute, then i am afraid a new 
top is indeed in order......

Richard Lees

On 6/18/2012 3:32 PM, Dana Emery wrote:
> First point, much of that which is black on musical instruments is 
> dyed maple and not ebony proper.  The wood used for a lute bridge does 
> need to stand up to the strings, but need not be as stiff as ebony, 
> fruitwood (pear, plum, apple) are recomended from what I recall.
> As has been pointed out your enemy is thermal mass.  A replacement 
> strategy allows destructive removal.  Working on the naked top will 
> allow the other repair you want to do, and in general you can 
> rejuvinate all the joints as you wish.
> cracks in the top of a lute are troublesome, and likely when an 
> instrument travels to a drier climate than that it was built in (er, 
> designed for).  A piano top is designed to have a slight but crucial 
> arch that keeps all the joints in compression as it dries out.  lute 
> tops are flatter than can allow that, and actually cave in in places 
> (especially between bridge and rose); rising in others (below bridge).
> An entirely new top might not be a bad idea at this point, but you 
> seem inexperienced for that, still should you have the resources, it 
> might be an opportunity to consider exploring.  You will want to make 
> thickness measuring calipers as well as a go-bar deck and perhaps some 
> other specialist tools.  The scrape of the present instrument can be 
> used for a model.  You might look for a violin maker in your area to 
> share a brew or two with and get some informal counseling.
> Good luck

---

From: sterling price <[email-masked]>
Date: Mon, 18 Jun 2012 20:13:11 -0700 (PDT)

Hi--I am sure that the bridge is ebony because I have drilled/enlarged
   several holes on it and its black dust all the way though. I am worried
   about the braces and the soundboard. Here in Utah the humidity often
   gets as low as 5-10%(like today).
   I am still looking for someone to do the work on this lute. Any ideas?

   --Sterling
   From: Richard Lees <[email-masked]>
   To: Dana Emery <[email-masked]>; "[email-masked]"
   <[email-masked]>
   Sent: Monday, June 18, 2012 8:12 PM
   Subject: [LUTE-BUILDER] Re: Archlute Bridge
   As usual,
   Dana Emery strikes again !
   Excellent post .......
   excellent post.......
   Sonically too, Ebony is not the most musical of woods and while I have
   retopped a beautiful archlute for a player out here which had ebony
   staves, one could lightly sense the enharmonic character of ebony in
   its sound... now for bridges,  Dana is right with respect to correct
   build procedures ......But if our mystery bridge turns out to actually
   be ebony ( and I have seen some pretty strange stuff done in our modern
   era with lutes) now would be the best time to replace it
   I especially like Dana's suggestion to check all joints !!!!!
   In the retopping of the archlute I mentioned above MANY braces (well
   over half!) had crystalized glue joints and so I  had to re-brace the
   entire instrument..... This instrument which was made by a pretty well
   known luthier was built in the late 70s.
   AND if the top is pushing 20 plus years , Dana's additional suggestion
   of simply putting on a new top is indeed called for...............
   A last note to Dana's post....
   some years ago i posted a quick observation on cracks, and its worth
   mentioning  it again.
   And Dana is yet again right on target....
   The Spanish masters of lutherie during the mid 60s  many of  whom I had
   the great honor to know , were absolutely firm on this issue.. We are
   to brace perhaps 5 or 6 percent LOW with respect to the expected
   humidity the instrument is going typically see.... This is to insure
   the health of the top and to make sure the top sounds well too.
   BUT there is another monster lurking here......
   If the players don't also agressively monitor EXCESSIVE HUMIDITY as
   when when the relative humidity is in excess of say 20  percent of the
   build target, then the wood will expand accordingly ... Now since the
   plantilla or shape of the instrument is fixed by the braces and bowl ,
   the softer top, as it expands,  has no where to go...
   What happens then is that the wood first bellies upwards and then
   starts to crush itself, under these high humidity conditions and then,
   when the humidity drops , the top can REALLY crack,  and whats worse,
   at a higher level of humidity even than the target build point!
   This occurs because by virtue of have been laterally crushed, the top
   is fundamentally NARROWER than before. When the humidity drops and the
   top shrinks even further, these catastrophic failures can occur.
   I restored several German harp guitars like this... The back of one of
   them, a Haberman instrument, had shrunk so badly that it lost over1/4
   of an inch in width relative to plantilla so that when I removed the
   back you could hear the instrument groan as the stresses were relieved
   and the sides started to reconform .
   If this is what has happened to Sterling's lute, then i am afraid a new
   top is indeed in order......
   Richard Lees

   --

References