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rem50
02-09-2011, 03:49 AM
I was wondering about what a uke is designed like inside. i have one I never play and want to take it apart to get a real good look at it. I also want to salvage parts so I can use the neck and bridge... to build a body of my own so..... My main question is how to start taking the body apart? Heat? Saw? How should I detach the neck from the body. Remember I am not afraid of demolishing/ruining this while I learn. THanks for the help. rem

Rob-C
02-09-2011, 04:19 AM
Surely half the fun is in coming up with your own evil method of uke destruction?

HornedOne
02-09-2011, 04:23 AM
it depends on what kind of uke you start with. if its a wooden backed one (no dolphins) I'd start with stripping the paint/laquer and seperate the back. that way you can see what kind of neck joint is used. (and you can put it back together if you want xD)

thistle3585
02-09-2011, 05:36 AM
If its made with hide glue then you can remove the back using heat and steam in conjunction with a thin knife. If its some other glue, I'd use a thin kerfed pull saw and cut through the seam where the back and sides are joined. There isn't any reason that you need to strip the finish especially if you want to put it back together. I'd start by making a cut with a razor knife around the perimeter of the seam so that you reduce the chance of chipping the finish. It may be that you could get a thin knife forced between the seam and gently "crack" it off without heat. I bet there's step by step instructions at frets.com.

thistle3585
02-09-2011, 05:40 AM
I found the link. http://www.frets.com/FRETSPages/Blogs/1867Martin126/1867Martin126_1.html#d2

rem50
02-09-2011, 08:05 AM
this is great info. Thanks guys. I should have told you this is a cordoba CK25 if that helps you all. Will keep this going so others can see what I went through.

rem50
02-09-2011, 09:06 AM
I have the back off. how do I remove the neck? rem

Sven
02-09-2011, 09:28 AM
Interesting. No bridge patch?

HornedOne
02-09-2011, 09:41 AM
and the bars next to the soundhole that run paralel to the neck are not symmetrical

or any fan bracing

thistle3585
02-09-2011, 09:46 AM
I have the back off. how do I remove the neck? rem
Try this.
http://www.frets.com/fretspages/Luthier/Technique/Guitar/NeckReset/00028Reset/00028reset01.html

Rob-C
02-09-2011, 09:48 AM
My gut feeling, and I'll happily bow to anyone who knows different, is that the neck will be dowelled on.

rem50
02-09-2011, 10:16 AM
I do not know what a bridge patch is and why would symmetry be important. I really hope to learn something here so I do appreciate your comments. @thistle3585.... thanks for the links. I have been looking at them. rem

rem50
02-09-2011, 10:21 AM
Try this.
http://www.frets.com/fretspages/Luthier/Technique/Guitar/NeckReset/00028Reset/00028reset01.html
do you think this is as intricately designed? there is just a block on the inside under the neck. I cannot tell how it is attached.

ProfChris
02-10-2011, 12:18 AM
Try this.
http://www.frets.com/fretspages/Luthier/Technique/Guitar/NeckReset/00028Reset/00028reset01.html

Don't do that yet!

Those instructions are for a dovetail neck, and you don't yet know what kind of neck joint you have. There are three main categories:

1. Bolt-on neck. One or more bolts run through the neck block (the block inside the body) and screw into fittings buried in the end of the neck. Can you see any bolts (often Allen bolts, requiring a hex key to undo)? If so this is comparatively easy. Undo the bolts and see if the neck starts to separate. If so, you just need to detach the portion of fretboard which is glued to the top - hot palette knife I guess. If not the neck is glued as well as bolted - hot knife time.

2. Glue and dovetail/tenon/dowel. The dovetail, tenon or dowel sticks out from the end of the neck and slots into the neck block, the whole being glued together. The Frets.com instructions should work for this. If it's dowelled you won't be able to see where the dowels are, even with the top off, and I'm not sure how I'd do this one - any ideas anyone?

3. Spanish heel. The neck and neck block are a single piece, with slots cut in the side of the neck into which the sides fit. It looks as if this might be what you have - there is a stripe of wood in the middle of the neck block, and if that carries on up the neck then I reckon it's Spanish heel. If so, check if the sides are actually glued into the slots - it's possible that they are just held in with slender wedges. If so you need to carve out the wedges (modified hacksaw blade?), unglue the fretboard extension and remove the top (or loosen the neck block to top glue joint), and the neck should come out. If glued, I've no idea what you do! Frets.com shows Frank Ford using an osteopath's oscillating bone saw to cut the neck off, but I doubt you have one of those. If no-one knows better, I'd try to widen the slots at the neck block side, and then use my hot palette knife from the neck side to try to unglue the joints.

BTW, that massive bracing explains why Cordoba ukes tend to be quiet - you could probably stand on the back without it failing.

SweetWaterBlue
02-10-2011, 02:37 AM
BTW, that massive bracing explains why Cordoba ukes tend to be quiet - you could probably stand on the back without it failing.

That is what struck me too. It looks house framing or something. That explains why the Cordoba acoustic/electric I had for a few weeks was dead acoustically. Not surprisingly, it was a very good electric uke, since it was not very susceptible to feedback. It always felt like it was built like a tank when you picked it up. Now, I am wondering what cracked both sides and the top and the bottom on the one I had - UPS got the blame, but they must have had some fun with it.

SweetWaterBlue
02-10-2011, 02:40 AM
I have the back off. how do I remove the neck? rem

Please tell us how you finally got the back off. It looks like it came off nicely.

rem50
02-10-2011, 03:08 AM
thank you for the options on getting the neck off. I am leaning that it is the spanish heel too. With all this info I can now look with my eyes open! Ha! As for the back coming off nicely you did not see the trash! I started at the back in the middle where all the binding met. (please remember I used the word demolition in the thread title:) ) I used a razor blade knife to get some off to start. When I finally got the knife thru to the inside I slipped a small wood chisel in there and started prying. I was going slowly then the laquer started cracking and so I busted the back off. It did break off relatively nicely though. What I am wanting to do is salvage the neck if possible and build a fun shaped body for it. I really wanted to get a good look inside and see how this is made and what contributes to the sound being bright or muffled. I am getting the idea it falls on the thickness of the bracing. What is a good bracing wood? rem

ProfChris
02-10-2011, 04:08 AM
thank you for the options on getting the neck off. I am leaning that it is the spanish heel too. With all this info I can now look with my eyes open! Ha! As for the back coming off nicely you did not see the trash! I started at the back in the middle where all the binding met. (please remember I used the word demolition in the thread title:) ) I used a razor blade knife to get some off to start. When I finally got the knife thru to the inside I slipped a small wood chisel in there and started prying. I was going slowly then the laquer started cracking and so I busted the back off. It did break off relatively nicely though. What I am wanting to do is salvage the neck if possible and build a fun shaped body for it. I really wanted to get a good look inside and see how this is made and what contributes to the sound being bright or muffled. I am getting the idea it falls on the thickness of the bracing. What is a good bracing wood? rem

If you don't care about the side and the top, the easiest way would be to cut them away. Then cut down through the neck block (stopping at the fingerboard!), and work out how to break the joint where the fingerboard joins the neck block/top. Heat, I think - try a domeestic iron on cotton setting, using a cloth to prevent scorching the fingerboard, and gently slide a blade under the fingerboard as the glue softens (if it does). If not, and you can saw precisely, cut it away.

This will leave you with a neck, with some fingerboard extending from it, and a neck block. You could make it bolt-on by putting a threaded insert in the cut surface of the neck and bolting through the block.

Sven
02-10-2011, 04:28 AM
You really think that's a spanish heel? I saw the stripe in the block too, but on the ukes I've built with a spanish heel you couldn't have seen the sides meeting in the middle like they appear to do in the pic.

S

rem50
02-10-2011, 06:17 AM
this is great info. I really am looking at the learning part and that is certainly happening! I will take some closer pictures later and post them before I start cutting. I did like the idea of converting it to a bolt on neck with whatever body style I come up with.

thistle3585
02-10-2011, 07:02 AM
I'm far from an expert on repairs, but I'd be tempted to drill a small hole about a quarter of the way down from fretboard through the block, but not into the neck, then insert a steam needle and see if you can steam it off from the inside out. The other way would be to simply chisel the block off.

rem50
02-10-2011, 11:39 AM
here are a couple of closer pics of the neck. Does this help? Any suggestions?

SweetWaterBlue
02-10-2011, 11:44 AM
I don't think its a Spanish heel for two reasons in those latest photos.

1. Spanish heels often have wedges inside between the sides and the heel. The wedges push the sides tightly against the outside edge so no crack shows. They also help to align the neck slightly if you need to when it is built It is possible that you don't need wedges with a good fit, but it just doesn't look like it here.

2. There is a big gap between the body and heel showing in the second photo that would not be there with a Spanish neck. The ukulele sides on a Spanish heel fit into slots in the heel. These sides appear to run under it just as they do on a bolt or glued on neck. l Can you see light through that gap?

rem50
02-10-2011, 12:55 PM
can't see thru it. is that "block" on the inside under the neck part of the neck???? Do I have to cut this out?

ProfChris
02-11-2011, 05:14 AM
You really think that's a spanish heel? I saw the stripe in the block too, but on the ukes I've built with a spanish heel you couldn't have seen the sides meeting in the middle like they appear to do in the pic.

S

Good point - I was struck by the apparent gaps between the neck block and the sides at the edges, and the stripe. Could still be Spanish heel if the slots were slanted?

ProfChris
02-11-2011, 05:25 AM
Good point - I was struck by the apparent gaps between the neck block and the sides at the edges, and the stripe. Could still be Spanish heel if the slots were slanted?

Just saw the new photos - PROB90 it's not a Spanish heel. No bolts, so it's not bolt on.

This means it's (a) dovetail - unlikely because that's more work manufacturing; (b) tenon (maybe), or; (c) dowelled (a cigar for Rob C if it is).

If you want to get the neck off while keeping the top and sides intact then the fretboard and the top must come off so you can see the joint from the top side. Fretboard first (heat, palette knife), then the top (same technique).

If it's dovetail or tenon, steam injection apparently works.

If it's dowelled, I'd chisel away the block until I saw the sides from the inside, which would locate the dowel(s). Drill them out, then separate the glue joint of neck to sides with heat etc.

If the sides and top are junk, cut down either side of the block and along the side of the fretboard extension until the neck is free. Cut off the block, retaining the fretboard. Attach by drilling through the new neck block into the neck and dowelling, or use a threaded insert and bolt it on.

mzuch
02-11-2011, 08:29 AM
I'm betting on an epoxied butt joint. What brand of cigar does the winner get?

SweetWaterBlue
02-11-2011, 08:56 AM
can't see thru it. is that "block" on the inside under the neck part of the neck???? Do I have to cut this out?

Only if its a Spanish heel.

joejeweler
08-04-2011, 04:40 PM
this is great info. Thanks guys. I should have told you this is a cordoba CK25 if that helps you all. Will keep this going so others can see what I went through.

Well,....the Cordoba 25CK has gone thru some bracing changes for sure. Mine is much too
heavily braced anyway, and although i have changed the cheap and ill fitting saddle to a hard african ivory one,.....it's output is still muted. That's the problem when you have a Moore Bettah soprano and a R. L. Saul concert to compare to!

My Cordoba 25CK has what i believe is the older style lazer inscribed headstock. The bracing is different also, as mine has a bridge patch AND a tapered brace that is notched to go over the
patch, and extending from the soundhole to the endblock.

When i got my Ron Saul concert in, which is a lightly built screamer, i noticed he only used a thin tapered spruce brace where a bridge patch would be. This is on serial #0003, not sure
if he changed bracing on later ones, and there are some light braces around the soundhole also.

I decided to use my Cordoba 25CK as my travel to the casino, beach, and other outings rather than risk injury or theft of my better ukes. The sound output needs to go up, however, and like
you i'm not adverse to a little surgery on the inside.

Unlike you, i am only going to rework the bracing, and not do a total teardown! :eek:

Specifically, i am going to try to remove entirely the brace going from the soundhole to the endblock. The bridge patch is fairly wide, maybe 3/4" or so and maybe 1/8" thick or a bit less.

Considering the Ron Saul uke used a much thinner cross brace in place of the usual bridge patch, i don't think i will have any top issues with the removal of this brace on the Cordoba.(other than factory warrentee issues! lol)

The soundhole is pretty small to work thru, but i'm going to work on making a brace shaver that i can usethru the sound hole before i go to the more extreme back removal. I've done
that before with an old Kays archtop, but the glue was 50 or 60 years old and i doubt the Cordoba 25CK will come apart so easily.

Anyway,....i guess Cordoba figured out they were overly bracing their ukulele, and your's looks like a later variation.

Here's your pick of the top bracing again:
http://i204.photobucket.com/albums/bb200/joejeweler/Cordoba%2025CK%20Ukulele/Cordoba25CKTopBracing.jpg

Rick Turner
08-04-2011, 05:05 PM
Man, that is some funky sh.t!

Tudorp
08-05-2011, 12:12 AM
I have one I played in a hot tub. It started coming apart on it's own a couple days later.. ;)

joejeweler
08-05-2011, 02:56 AM
Man, that is some funky sh.t!

Man of few words! :D

Gmoney
08-05-2011, 04:47 AM
Man, that is some funky sh.t!

What he said! Just amazed that ANY vendor let this uke off the workbench. That build job looks like a 5-year old put it together using wood pried off the side of an old barn.

joejeweler
08-05-2011, 06:58 AM
What he said! Just amazed that ANY vendor let this uke off the workbench. That build job looks like a 5-year old put it together using wood pried off the side of an old barn.

My Cordoba 25CK is much cleaner than that inside. The kerfed liner is pretty even and not a lot of excess glue, and the braces have been sanded ,(although a bit too heavily braced)
The one the OP is tearing down appears to have a solid liner of varying thickness, and the soundhole braces look to have those "afterthought" blocks placed on the ends. Looks like a newbee........

Guess it's the luck of the draw,....get a worker well rested and fairly competent,

....or get one off a full night's drinking! :uhoh:

I prefer the former.