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I recently purchased this turn of the century Bruno Bowlback mandolin with a pearl fingerboard.  As you can see, it's missing several sections of pearl which I intend to replace (including the abalone inlaid in pearl section which I'll have done by a pro) but the real issue will be a neck re-set.  To remove the neck, I'll have to either remove the fingerboard or loosen the fingerboard extension, both of which I have done many times, but not with a pearl fingerboard.  

What little I've found online about pearl fingerboards suggested that the pearl will pop off easily and could be damaged with out much effort and the 4 missing sections correspond with the area of the neck that has bowed the most supporting that idea.  In addition, the fingerboard under the pearl seems to be quite thin.  I'm concerned that normal techniques like heating and prying could do serious damage.  

If anyone out there has any experience with this, I'd appreciate their thoughts on how best to proceed or where I can look to find that info out. I've tried searching this forum and Mandolin Cafe with no luck.

Thanks very much.

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General rule around these parts is that the pearl all has to come off, the neck secured/straightened and fingerboard replaced and leveled.  Then, the pearl and new frets get glued in place, with appropriate size new pieces as needed.  Binding and setup add to the adventure.

This is the kind of repair that typically exceeds replacement value of the instrument by such a margin that we usually decline the job unless the owner has extreme sentimental attachment.  

(Much as I now hate to use the word these days, I've always said that sentiment can trump monetary consideration. )

And, as a matter of fact, we're currently doing a complex restoration on an old Martin guitar that will exceed it's resultant cash value by a factor of three (at least).

Thanks for the feedback, Frank!  I was afraid that might be the case.  I'm still at the "learning by doing" phase of my self education in instrument restoration so I don't mind the extra work, particularly if it results in bringing a remarkable instrument back to life.

I put more hrs into restoring a Washburn 1897 Style New Model 145 than it will ever be worth, but learned so much from the process that it was well worth the time.  My hopes are that, over time, the hrs vs $ formula will eventually move to the point where I can break even then eventually move into the black (years down the road!).  

I assumed that I'd need to do a neck re-set on this to make it playable again.  Is that viable on a bowl back with a shorter length than a guitar?  I suppose I could also take off the fingerboard and plane the neck and or fingerboard to level things out again. Any idea what sort of a neck joint I might be looking at here?  Of course, if I pull the fingerboard, I should be able to see.

At any rate, I move slowly since this is currently a sideline for me, but I'll post pics and keep everyone in the loop as I progress.  

One quick question... gentle heat to remove the pearl?  Perhaps a bit of water as well?

Gentle heat and water is the way to do it. I would remove the frets and the celluloid bindings first to be able to use more heat, then the whole fingeboard with the pearl inlays using two cooking spatulas like this,The best ones are thinner at the tip, about 0.3 mm thick, and the sheet metal formed like a wedge. If they are thicker they can be sanded and shaped to a wedge with a thin tip. The tip shall be sharpened with the edge on the top side not to dig into the soft spruce under the fretboard. The sides shall have the edge in the middle. After getting one spatula under the fretboard, the other one can be pressed in on top of the first. Using the two spatulas always overlapping like this decreases the possibility for the spatula to dig into the soft spruce on the top. The one on top can be heated on an iron and/or dipped in water to melt the hide glue. Using a side to side rotation motion of the top spatula is the best way to dig deeper into the glue line.

Once the fretboard is loose from the top, the sides of one spatula is used to follow the glue line between the rest of the fretboard and neck. The spatula trapped flat under the fretboard will follow the seam nicely.

Beware of the sharp spatulas and use some leather or butcher gloves when using them. They are knifes!

Once you get the fingerboard off, you will have a better idea how to proceed. There is no standard neck joint strategy for bowl backs. It could be a dovetail or a dowel connection or the equivalent of Spanish guitar construction where the neck and neck block are all one piece, like in this image of one I spent way too much time on... or???

You may end up best off to manipulate the final neck angle by tapering the fingerboard thickness. Here is a link to a site I found...some interesting information there.

http://www.mandolinluthier.com/index.htm

Thanks everyone!

I'll give your method a try Rodger.  I like the double spatula method.  I usually use just a single putty knife, but I see the wisdom of the second blade protecting the top.  

Paul, that's a great site with excellent information.  I learned more about bowl backs in the last 1/2 hr than I have in all my trial and error efforts!  I can see I have my work cut out from on this project, but I think it's well worth the effort.  

I'll let you know how things proceed.

Thought you would find that site useful, there is not much repair guidance out there for bowl backs.

Wish I had found it before rehabbing the Neapolitan in the picture but I did get this one done "seat of the pants". Finished it in 2005 and the action hasn't budged, it's a good player.

I have Martin M400 strings on it in the picture from 2005. Light, low tension strings are necessary for bent top instruments. I eventually upgraded to Thomastic strings. The G, D and A are flat wounds and plain steel for the E. They sound a great deal better than the Phosphor Bronze Martin M400's and last a lot longer, which is good, because they are also $pricey$.

Post some pics as you go.

Very nice work!  It looks like the one in pieces pictured above.  I assume you saved and re-used the original binding.  I also see what appears to be a truss rod plate on the headstock.  Is that decoration or did you add a truss rod or neck stiffener of any kind?  

RE stings, I've got an endorsement deal with John Pearse Strings and have exclusively used them for years.  I always use light gauge on vintage instruments.  I think John Pearse may have  designed some of the Thomastic strings for violin years ago (though I couldn't swear to it).  Now that I think if it, this mandolin currently has flat wounds on it now.  I'll have to see if they offer flat wounds. 

The web site was great.  That's the first site I've been to that had in depth info on bowl back repairs.  I wish I could blow up the pictures, though, and get a better idea of possible construction styles.  

The good spatulas are not that easy to find, nowadays it's usually plastic spatulas for Teflon pans. Here in Sweden one of the biggest supermarkets "ICA" happens to have them. The brand is "Cook & Eat" if that helps.

Yes, one big advantage is that the spatula below protects the top while working with the one above!

That's the attraction for me, that and the large size spatula (I'm used to putty knife sized tools for loosening a fingerboard) spreads out the stress and might reduce the potential for damage.

I'm going out later to see what's available here.

OK, I located a similar spatula (though narrower) and honed the edge as instructed.  As soon as I began to gently explore the situation, it became clear that the pearl was almost completely loose and essentially being held in place by the binding, which itself was very loose.  I took Frank Ford's advice and removed all the pearl and frets and did this by attaching a strip of low tack masking tape to the pearl and frets and gently lifting.  I only had one section that required an little teasing to get loose and the entire pearl and fret overlay came off in 2 pieces, in correct order attached to the tape.  I then taped these sections to a piece of scrap spruce for storage and later re-use.     

I had also begun removing the binding which took fairly good chunks of the underlying fingerboard with it.  There are clear signs of previous attempts to repair the instrument.  I could see that someone dumped either white glue or titebond along the edge of the fingerboard and let it "soak in".   I'm sorry to say that the underlying fingerboard material was probably pear wood or some similar wood that had been "ebonized" and is in seriously deteriorated condition.  I do not expect to be able to re-use this (and I try to re-use everything) and will be lucky to get it off intact enough to use as a template for a replacement.  The blue tape in the middle of the fingerboard in the pic below is holding broken pieces of the fretboard in place.

Replacing the fingerboard will present a whole news et of challenges.  First, I've got to get this one off and see what's going on inside the instrument.  Clearly I've got my work ahead of me!

Yes, I did save and re-use the wood binding. It was missing some pieces, which I recreated and filled in.

What looks like a truss rod cover is just decorative. It's a small piece of tortoise shell and some bone inlayed into that. The rest of the inlay and dot markers are all made of bone which matched the original White celluloid of the pick guard and tuner buttons pretty well. The current Cites laws would have this instrument taken away if I ever left the country with it because of that bit of Tortoise shell I put in there.

Don't have any better images of it than this on file.

Mine had the dyed Pear wood finger board too. Don't re-use yours, the dye used is acidic and it will continue to degrade. In you case, it won't matter so much what kind of wood you end up using, it will all be covered. It will also be much easier to use new finger board binding than trying to re-use the old stuff.

When you get the finger board extension removed from the top, you should be able to see if has a dovetail joint but there is also a possibility that a dove tail could have been used but then covered by the top. If the top covers whatever is there, I would remove a small bit of the Spruce top to get a look at the neck connection. You will replace it and then cover this cootie later on with the new finger board.

I get palette knives, available in many sizes/ configurations at art supply stores. I also keep an eye out for them in second hand and junk shops, stainless steel is best. Regular steel can leave Black stains in the wood, especially if you use any vinegar based glue solvents like Deglue Goo.

The journey begins...

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