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I just bought a Kentucky Mandolin KM-805 with a broken head and wonder if a neck is available but can't find the manufacturer or a spare neck elsewhere.
It's in the post, so I don't know if a repair is possible but a neck replacement would of course make it as new again.
EDIT: I found the company: https://www.sagamusic.com/products/mandolin-family/
https://i.ebayimg.com/images/g/9VcAA...DZ/s-l1200.jpg
Mandolins really aren't like electric guitars where you can simply buy a new neck from someone that has them in stock. Saga Music is indeed the importer of Kentucky brand mandolins. They own the name and over the years the production has shifted between Asian countries depending on who Saga was doing business with. I believe I heard that they now own their own factory but that may or may not be true.
Any decent luthier familiar with mandolins could make you a new neck or perhaps repair the one you have. Without pictures nobody can tell. In the end you will probably pay more to have that re-necked than you would to buy a new instrument. Post some pictures so we can at least give you some intelligent advice.
Mr. Hansen, if the instrument had sentimental value - clearly not, or was worth more than the repair - probably not, unless you could find another wreck for free and do the work yourself, and the one you bought was suitably inexpensive , then maybe.
I wouldn’t rule out either a head repair or a neck transplant simply based on either economics or likely failure; we do what we like in this particular microcosm. I tend to fix things for fun, so if I found this item free or was given it, and if the rest of it was iintact, I’d probably dowel, plate and glue the head together just to see if I could, and if it was a matter of an hour or so. And play it.
The truss rod channel at the break means there is not much "meat" left to work with to effect a proper repair (without taking heroic measures) This repair by Jerry Rosa is almost exactly what you have there.
https://www.youtube.com/watch?v=5vCw2F4EcE0
Phew, that video sets the bar quite high :-)
And that’s only part 1. The second video has even more failed efforts, and more trouble expanding the scope which is a good reason for watching Rosa: even with all that experience, he doesn’t edit out mistakes. I can’t estimate how many hours went into this, or whether luthiers in Denmark work massively cheaper than in the US (!), but this job goes deep, deep, deep into expensive anywhere.
The bottom line on neck repairs:
1. If the break is long, and more or less with the grain, and no previous repair attempt has been made, it can be glued with a reasonable chance of long-term stability. Titebond Original or hot hide glue are the only glues I would recommend. The glue joint must fit as closely as possible. The joint can be reinforced by installing a "back strap" and/or replacing any sections of the peg head face plate that are broken or cracked.
2. If the break is short, or runs perpendicular to the grain, or there is a lot of missing wood, the most reliable way to repair it is either to graft on a new peg head with a long glue joint, or replace the neck.
3. If a previous repair attempt has failed, it will not be possible to get a reliable glue joint. It would be necessary to cut everything back to bare wood, and install a graft, or replace the head or neck.
I do not know what kind of joint was used to attach the neck on your mandolin when it was built. If you replace the neck, check inside with a light and a mirror to see if any screws or bolts were used to attach the neck.
If you decide to replace the neck and cannot easily purchase a replacement from the manufacturer, I do not know of any supply houses that will sell a neck alone, but somebody else on the Cafe might. There is a fellow selling mandolin neck blanks in the classifieds under "Mandolin Accessories." The ad number is 162322. You would have to do quite a bit of work to finish and assemble the blank, an you will have to find out whether he can ship to the EU. If all else fails, a violin maker can probably make one for you.
An idea: You could check with one of the mandolin builders in eastern Europe and see if any of them will sell you a semi-finished neck. Prucha comes to mind as a possibility.
It came today, here are pictures. Luckily the old glue was water soluble, so a couple of hours cleared it up.
I will try to glue it, but there isn't much wood there with the narrow neck and a trussrod. It's preprogrammed to break there. I am contemplating to remove the trussrod and insert a carbonrod, that reaches into the head.
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Good job cleaning out that old glue!Quote:
Originally Posted by poul hansen
That could be a candidate for a successful back strap repair.
Rosa’s issue with the truss rod was that it was bi-acting and wouldn’t come out without pulling the fretboard. If yours just unscrews and comes out, replacing it with a fixed brace sounds good, but if, instead of carbon, you could make something with a suitable bend at the peg head, it could extend further up beyond the break. I’m thinking aluminum or titanium if you have access. Then, a plate on the back could bolt right to it.
If the truss doesn’t want to unscrew and remove, but you have threads showing, you could make an extension too.
My question, which the photo doesn’t clarify, is what’s going on between the scroll and the body? Another old repair?
There is another old repair of the bigger scroll on the head. I was glued a bit askew and with I believe, cyano glue but I could scrape the edges flush, so I only have to colour match the scraped areas.
I am going for an epoxy gluing of the head. It has held as it were and the glue joint should be stronger than the wood ;-)
For now I am a bit apprehensive about removing the trussrod, as it was already tightened all the way. I fear that the neck might bend under string pressure without it.
Truss rod tightened all the way...? You mean it is snugged up, or cranked to the thread limits?
How does the fretboard look for straightness right now?
I also recommend adding a back strap to cover the break. You would have to mill out a small amount of material and do some re-carving to make it work out.
You might also want to consider replacing the head veneer from the nut to at least the first "point" of the peg head. I might go as far as the first set of tuner post holes.
If you handled it that way, you would be making a "sandwich" that covered the break entirely.
As far as the truss rod is concerned, that's a judgement call. You do not know what kind of glue was used to attach the fingerboard to the neck. If you have to open that joint, the best case would be that it would come apart easily with judicious heating. The worst case would be that the joint will not respond to heat at all, and then you would have to either cease and desist or grind off the fingerboard.
See if you can determine whether or not the truss rod is functioning at all. If it is functioning, it might be best to leave it alone. If you do have to pull it, it would be best to do that before you repair the head.
It can't be turned anymore clockwise. The fretboard is straight but maybe the rod stabilises that when the strings come onQuote:
Originally Posted by Eric Oliver
I always try the least intrusive way first. I'll try to keep the head veneer but somehow patch or replace the thick plastic or 2 component laquer that covers it all. That way I also avoid the risk of damaging the binding.Quote:
Originally Posted by rcc56
What is leading you to believe there was an old repair?Quote:
Originally Posted by Richard500
The way there’s a stray piece of binding and a boundary of some sort that I might understand if I were familiar with this design. I wasn’t referring to the scroll break on the peg head, which I think Poul describes, but is invisible. The immobile rod nut is also curious as I imagine there’s always surplus thread unless there's some failure in the wood seats from overtightening. Also, the black veneer looks like wood at the break, not plastic.Quote:
Originally Posted by MikeEdgerton
Someday, after Liberation, I’ll maybe get to see an F, or even play one.
I'll get a picture of the nut area but I am about to glue it.Quote:
Originally Posted by Richard500
The head does have an overlay in wood but on top of that is a very thick plasticky layer, maybe 2 component lacquer.
Whatever you do. the repair is going to have to be strong enough to withstand 90 + kilograms of constant string tension. If the instrument came to me, I would want to find a way to reinforce the break, rather than rely on the new glue joint alone; especially since a previous repair attempt failed to hold.
That "repair" was totally amateurish. Made with white glue on parts that didn't fit together. Look at the amount of glue on the parts, they didn't fit and weren't pressed together.Quote:
Originally Posted by rcc56
As the trussrod is already at the maximum tension, it can't do anything more for the neck, so I might glue it in and place a reinforcement in the cavity going through the two broken parts.
Poul, if you haven't already glued up the neck I think it would be best to give it another day or five if you were at it with water cleaning up the first glue job.
You have a point about the first glue job, but rcc56 is giving you good advice on a long term repair.
I wouldn't go for epoxy if the fit of the parts after cleaning is reasonable but rather hot hide glue and good clamping to prevent slipping and provide good alignment. That alone would likely be good enough but simple backstrap overlay will secure it for years. You can do just 2-3" long overlay 1/8" thick tapering to zero thickness at ends bridging the crack at the back of neck.
The wood looks like curly mahogany (correct me if I'm wrong?) and that will suck some glue so count with that. Don't mess with truss rod and fingerboard removal, you can get into more trouble and if it ever really needs to be removed you can do it later as well.
Check every article that Frank Ford wrote about headstock fixing...
That is actually part of the riser block. It's part of how Gibson attached the neck on their mandolins. You'll see it on Gibson A's back to the beginning as well as F styles. They dropped it on some A's in the 40's, maybe into the 50's.Quote:
Originally Posted by Richard500
Here's an update.
I glued the head on with Titebond but here was a bit of wood missing at the end of the break, so I filled it with a little filler.
I cut 2 pieces of wood in an angle and double taped them to the neck, to get a correct angle of pressure, to avoid the head sliding.
I then had a lot of problems remaking the finish, every filler and spraypaint were incompatible with the mandolin and each other.
I had reasonable success and stringed it up. It held! and I could play it. Really nice sound, what I was hoping for in an expensive instrument like this.
After a few days though, a very finde crack developed only where I had used the filler, so I thought the wood was bending naturally and the filler couldn't follow that.
To be sure it wouldn't develop, I very carefully pressed down on the head, to see if the crack would expand. IT DID. The head broke off in a different place! It looks like the neck is weak, because of the grain not going straight but at an angle of about 30 degrees and there is almost no wood left around the trussrod bolt cavity.
Again I glued the head but this time I glued in the trussrod and a piece of aluminium tube at the end of it, cut out a groove where the filler was and glued in a piece of wood. I remade the finish, with the same compatibility problems as before, even though I bought a filler spray supposedly compatible with the spraylacquer.
I stringed it up and it held but after a few days a finer crack developed at the end of the inserted wood. This was an endgrain glue, so maybe that's the problem. I wanted to take a change, that the glue had been sucked too much into the wood, to I saturated the crack with very thin superglue and haven't remade the finish yet.
I've stringed it up and played it for 14 days and no ever so fine crack has developed.
The morale of the story: Never remake the finish until you are sure of your repair :))
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