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View Full Version : How to replace damaged soundboard on a tenor ukulele?



Steve in Kent
08-05-2016, 12:37 AM
I'm just about to source a nice, (hopefully), AAA grade Alpine Spruce soundboard to replace the damaged one on my tenor ukulele.



Would anyone be able to provide me with a link to show how to remove the damaged one, and replace with the new one please?

Never attempted anything like this before.

Thank you,

Steve

Timbuck
08-05-2016, 03:15 AM
Look on YouTube for "replacing a guitar sound board/top" one or two videos there.

Michael N.
08-05-2016, 06:48 AM
You sure you want AAA if you've never done this before?

pointpergame
08-05-2016, 06:53 AM
In general, if the top isn't put on with hide glue, I cut the top off, just far enough inside the periphery not to nick the linings. A saw always feels too violent for my taste, so I ( basically ) cut a big X in the top with a sharp knife, then pare back the top. Unless I want to preserve the top, as in the repair of a violin, I cut the top off even if it's held on with hide glue. In that case having only the little narrow rim to take off with heat and water is usually less destructive than trying to "slice" it off with very thin hot spatulas.

From there I use a very sharp jointer plane to plane off the little top rim that remains until the original glue just disappears. A very sharp block plane or mini plane will work, but it's really hard to avoid inducing waves and cutting below the original glue line. If you don't have appropriate planes, and most people don't, you can go the traditional route of glueing sandpaper to a very flat 2" x 4" length of hardwood ( or any-sized chunk that is flat and won't deform ) and using it like a jointer plane. I've seen videos where builders have glued sheets of sandpaper to a sheet of plywood and then scrubbed the shell across that ( up side down ).

In any case, once the top is off, the procedure is practically identical to jointing the top on a new build...except there is likely to be a skin of stubborn glue sitting atop the linings.

Timbuck
08-05-2016, 09:30 AM
In general, if the top isn't put on with hide glue, I cut the top off, just far enough inside the periphery not to nick the linings. A saw always feels too violent for my taste, so I ( basically ) cut a big X in the top with a sharp knife, then pare back the top. Unless I want to preserve the top, as in the repair of a violin, I cut the top off even if it's held on with hide glue. In that case having only the little narrow rim to take off with heat and water is usually less destructive than trying to "slice" it off with very thin hot spatulas.

From there I use a very sharp jointer plane to plane off the little top rim that remains until the original glue just disappears. A very sharp block plane or mini plane will work, but it's really hard to avoid inducing waves and cutting below the original glue line. If you don't have appropriate planes, and most people don't, you can go the traditional route of glueing sandpaper to a very flat 2" x 4" length of hardwood ( or any-sized chunk that is flat and won't deform ) and using it like a jointer plane. I've seen videos where builders have glued sheets of sandpaper to a sheet of plywood and then scrubbed the shell across that ( up side down ).

In any case, once the top is off, the procedure is practically identical to jointing the top on a new build...except there is likely to be a skin of stubborn glue sitting atop the linings.
What about the fretboard ?

sequoia
08-05-2016, 05:09 PM
Yeah, ya get that fretboard off there to get at the bits of top underneath but other wise as Pointpergame said. The whole point is to not damage that seam at the sides because that entails hiding the gouges etc. Then the hardest part is finishing off the top and matching to the sides. The few times I've done this I ended up taking the sides down and re-finishing both top and sides for a good final fit and finish and hide. I will also say that the first time I did this, it was a major learning experience. Good luck! Send pictures.

pointpergame
08-05-2016, 07:30 PM
What about the fretboard ?

It's fiddly, but once the soundboard is mostly removed, the underside of the fretboard isn't all that hard to clean off, depending, of course on the original glue used. Don't you think? Then the soundboard has to be a thickness that just snuggles to the underside of the fretboard peninsula while still meeting the sides. Of course, the proper way is to remove the fretboard.
My only authority on this is having muddled through it a half dozen times over the years. The last project along these lines was converting a Sears Stella guitar to a credible party beater for my son. In that case it demanded a new fretboard and a new scale anyway.

Timbuck...you're an inventive luthier. How do you do this?

BTW...I meant to console you. I think cutting dovetails and pins on the wrong ends or cutting a set of mortises on the wrong side of a table leg are among the occasional random dangers of wood working. On your goofed up tap shave that sucker off, glue on a creative bridge that just covers the glue patch and recite, "What a good boy am I!"

sequoia
08-05-2016, 08:06 PM
It's fiddly, but once the soundboard is mostly removed, the underside of the fretboard isn't all that hard to clean off, depending, of course on the original glue used.

Don't forget the neckblock is in there. The fretboard isn't in the air. How are you going to remove the top between the neckblock and the fretboard with out taking off the fretboard? That would be quite the trick.

Steve in Kent
08-05-2016, 08:21 PM
Thanks for all the advice.

The better quality soundboard only costs an extra 10 or so, so in the scheme of things, not a lot of money.

This is going to take me hours of "fun" to do....

Thanks again,

Steve

Michael N.
08-05-2016, 08:36 PM
Don't forget the neckblock is in there. The fretboard isn't in the air. How are you going to remove the top between the neckblock and the fretboard with out taking off the fretboard? That would be quite the trick.

Pull the nearest fret that is just off the soundboard, carefully saw through. No need to remove the entire fretboard. The extension can be saved and reused although a slip of matching veneer will have to be used to fill in the saw kerf. I've done this a couple of times and it's impossible to tell that it's ever been done, especially with ebony.

Timbuck
08-05-2016, 09:44 PM
Timbuck...you're an inventive luthier. How do you do this?

BTW...I meant to console you. I think cutting dovetails and pins on the wrong ends or cutting a set of mortises on the wrong side of a table leg are among the occasional random dangers of wood working. On your goofed up tap shave that sucker off, glue on a creative bridge that just covers the glue patch and recite, "What a good boy am I!"
removing tops and fitting new one aint easy and if it has bindings harder still, you dont have to remove all the fretboard just the part over the body I used a hot pallet knife and heat gun.... problems come when you get to the ends of braces and getting round the blocks, if you are going to replace the top don't forget about the bracing pattern and the bridge patch on the new top and how are you going to replicate it if you just rip off the damaged old one....I found removing a back wasn't too dificult..Putting the same one back on exactly where it was to start with.. was a nightmare co's the sides had distorted, as what will happen when you remove a top and then you will have to find a method of lining up the neck angle cos that will be out.

As for my goofed up top it went straight in the bin...I find it's less stressfull and quicker to make another one..instead of fannying about with some thing that will only go wrong again later down the line.

Steve in Kent
08-06-2016, 03:12 AM
Hmm, looks like I will have to replace the white plastic binding as well. Sanded that down to the purfling too.

pointpergame
08-06-2016, 10:18 AM
Don't forget the neckblock is in there. The fretboard isn't in the air. How are you going to remove the top between the neckblock and the fretboard with out taking off the fretboard? That would be quite the trick.

A hack saw blade or coping saw blade ground down ( with the set ground off, of course ) will yank out the left over sliver of soundboard. Spruce, anyway. Though getting the glue off is the big problem. There's a wide range of cheap blades available and in the worst case they can be thinned with a rotary sander. This from my "farm boy wood worker" era of making instruments. Granted, it takes some mighty contortion and some minutes of patience to saw the saw ... but I see it as a bunch of tiny chisels mounted on a convenient plate and the blade can be cut in two to make a short one and a long one.

But this is a pretty desperate measure. The sloppiness of all this is too much for my modern sensibilities. I'd take the fretboard off, depending on the sequence of destruction that would cause. I don't remember having saved too many fretboards in this process, but these days they are readily available and not to awfully expensive. I have a $15 dollar laminate in the shop where the smart thing seemed to be to take the fretboard extension off at the 12th fret and glue it back on as suggested. I just don't play up there and I doubt the child I give this instrument to will either, so it could even go without.

sequoia
08-06-2016, 05:45 PM
Pull the nearest fret that is just off the soundboard, carefully saw through. No need to remove the entire fretboard. The extension can be saved and reused although a slip of matching veneer will have to be used to fill in the saw kerf. I've done this a couple of times and it's impossible to tell that it's ever been done, especially with ebony.

I've never done this, but this seems to me the easiest, smartest way to go. When I've taken off fretboards I just take the whole thing off. It gets easier as you go up. The hardest part is the beginning part and then the thing get skinnier and plus I get into a zone... I've always been able to save the fretboard too. It will curl like a caterpillar from the steam so immediately clamp it flat for later... It is hard, but not that hard. Two things: 1) Patience. Don't force things. It will give it up, and 2) you will be working with sharp hot objects as you try to get underneath it. Things tend to slip really fast and don't hurt yourself. Seriously, you could not only cut yourself but burn yourself at the same time. Could ruin your whole afternoon. It looks messy and is pretty violent, but things work out in the end. Don't crack the fretboard! Only pry when it wants to give. Patience is key. Also, I've been able to retrieve the top bracing after all is demolished. A bit of fiddling and prying on the left over bits, samd down to fresh wood and go. Good luck!

Steve in Kent
08-06-2016, 07:24 PM
The soundboard has been replaced before, and it looks like the neck has already been removed once.

It's feeling more and more like I will just leave it to see what happens, it still sounds the same.

Michael N.
08-06-2016, 08:59 PM
There's a mantra in repair/restoration: do as little as possible.

Steve in Kent
08-07-2016, 08:37 AM
There's a mantra in repair/restoration: do as little as possible.

Think I'll go with that mantra, it feels like a good one.....

Steve

sequoia
08-07-2016, 05:49 PM
I don't see any damage to the top in the picture. Only a piece of binding that has separated and lifted and that is an easy, easy fix. The top appears ok.

Doc_J
08-07-2016, 06:04 PM
I don't see any damage to the top in the picture. Only a piece of binding that has separated and lifted and that is an easy, easy fix. The top appears ok.

I agree. Wouldn't it be easier to do some repair ?

But in any case I'd love to see pictures of the work.
http://forum.ukuleleunderground.com/attachment.php?attachmentid=93192&d=1470547474

Steve in Kent
08-07-2016, 10:14 PM
The damage is of my own making.

When I got the ukulele it was stained brown, and when I tried to remove the strum guard, the stain came of with it showing a nice piece of spruce.

So I thought I would sand it down and get back to plain wood.

The whole episode is here http://forum.ukuleleunderground.com/showthread.php?119821-Trying-to-bring-new-life-to-a-well-used-abused-ukulele

What you are seeing is over enthusiastic sanding between attempts at getting a nice finish.

I have sanded through the top into the wood underneath, including the binding.

The "abalone" is plastic.

This poor ukulele has already had it's top replaced as it's solid, but originally was laminate.

Steve in Kent
08-09-2016, 07:20 AM
I may be saved by a friend who knows a local guitar luthier.

Steve in Kent
09-01-2016, 07:14 AM
Soundboard now joined by said luthier, and I have found a local cabinet maker who will reduce the thickness from 3mm to 2mm for me.