neck tenon

[Gerry Garavaglia]

 what is your technique of choice when repairing a neck tenon on an old kay archtop. It chipped on both sides when disassembling.

[Ron Frazier]

Glue wings back on it and re-carve it.

Ron

[Ned Knepp]

Hi Garry,

I'm in the process of rebuilding one of these right now too. I'm an amateur and haven't done a "reset" this extensive before but the guitar isn't worth much so.....

I got the guitar with the neck and body already separated so I can't say exactly what happened. The neck side of the dovetail looked like someone pulled the neck through the joint instead of pulling it up from the top, with almost all of the beveled slope chipped away.

I decided to cut away what was left leaving a straight and square tail with nice flat gluing surfaces where the bevels were. I glued two blocks of scarp spruce to these flat surfaces then recut the bevels using my chisels. On the first try, my ability to get the bevel symmetrical on both sides was tested and found lacking. I removed the mess and started again. This time things worked out better but I'm finding that the slot in the body appears to be "loose" at the narrow end which I think may have contributed to the joint failure to begin with. It's certainly hard for me to fit.

Maybe someone with much better knowledge can save you the headache I've been having as I try to get this right.

Ned

[Gerry Garavaglia]

Ned a good trick is to use carbon paper to dry fit the neck, after you add shims for the reset or in this case the new wood on the tenon place a strip carbon paper on each side of the dovetail and fit in the neck , remove the excess wood where the carbon leaves marks. Its a tedious process but this seems to be the way most luthiers fit the tenon to the dovetail.

Gerry

[Ned Knepp]

Hi Garry,
I did use carbon paper as you suggested. It is a bit tedious but it's the only way I found to "zero" it in. The first try was a mess because I got so busy cutting the tail and trying to make the joint tight that I forget to make sure the joint was even side to side. The neck was almost down when I realized that it was higher on one side than the other and the fingerboard was not square with the top. That's when I cut off what I added and started again. ( I took a couple of pictures of the tail as it is now but I'm having trouble downloading them to my PC. If I can get them, I'll post what I have. )

Cutting the tail to fit a pre-existing slot while keeping the neck straight and the heel angle correct is turning out to be a real test for me. The second try turned out much better but I found that the slot appears to widen out a bit at the bottom which means that my joint is tight right up to that final quarter of an inch or so of drop then it suddenly gets loose as it drops into place. I guess that I need to add some shims to the lower sides of the slot but I worry about that because I have two glue extra joints that don't belong already.

Fortunately the guitar is mine so time /effort are not a major issue. If nothing else. it's been an education. The only other resets that I done was a mandolin and it was a straight reset without rebuilding the tail.

Ned

[Marty]

Got a picture there Gerry? Hello from the frozen North.

[Gerry Garavaglia]

here are some pics of the tenons I already started to pare them down.

[Ned Knepp]

Garry, this is what mine looks like now. It's a cell phone picture but the only one I can get right now.
It's just about cut to fit but I still have to deal with the looseness at the bottom of the slot. You can see how the bottom of the slot is rounded in the third picture. This is what caused the fit to loosen when I cut the first tail. I think I'm going to have to fill this and cut it in the slot before I finish cutting the tail to fit.

[Gerry Garavaglia]

Ned how did you make out on your neck rest? I just glued up my archtop kay neck. I added material to the tenon and tried to change the angle and fit the tenon at the same time and it was a bit loose when it was seated all the way down so I added acouple thin shims and re fit it with better success. It was a pretty tight fit so I am hoping for the best.

Gerry

[Ned Knepp]

I haven't finish it yet, Gerry. I got side tracked on other aspects of the restoration. I have been drop filling chips on the body which takes FOREVER and I found that the fingerboard was coming loose.

I removed that and found that steel rod was loose in the slot plus the cut ends of it were left with a ridge which protruded above the top of the slot and pressed against both ends of the fingerboard. I also found that the rod was not straight but actually bowed a bit.

The neck appears to be basswood and has a lot of dents and damage. There are even a couple of ridges which appear to be caused by a very tight capo. Since I have it all apart, I'm considering completely refinishing the neck but it has a faux tiger stripped/ sunburst finish which I have no idea how to duplicate. In short, I am stalled.

I have the dove tail just about fit. It's tight and is only about a sixteenth of an inch short of down but I don't want to finish the fit until I get the fingerboard back on. I may need a small shim in the final fit since the bottom of the joint was not accurately cut. This whole thing would have been too expensive to pay for so it's a good thing I'm doing this as a hobby.

BTW, I'm having trouble identifying my guitar. Unlike most of the Kay archtops I've seen, it has a rosewood face plate but the standard, silk screened Kay logo and the head, neck and body are fully bound. The real kicker is that it as two strips of checkerboard perfling on the body and everything I can find only indicates one. I'm starting to wonder if this was done to cover a mistake in cutting the groove on the edge of the top.

[Gerry Garavaglia]

Ned, I have included some pics of my Kay arch-top. It has a couple numbers inside it. Looking into the f holes on one side it says N-1 and a small 839 inside the other f hole it says L 5777. The pics pretty much show all the identifiable things. The pics aren't sharp enough to show the heel joint very well but it is I believe a pretty good fit.I have three more old guitars to do neck resets on. I bought up a bunch of old kays and harmonys just for this reason and they sat for years now it is time to get good at resets. There is money to be made doing them if you have the patience. The back of my neck is just a standard sunburst.

[Rob Mercure]

Hey Ned,

How sure are you about the bass wood diagnosis? Tilia species are really soft and fine, even grained and seem a truly odd choice for a neck as they really don't have much bending strength at all. Since alder and birch and even "yellow" poplar (Liriodendron) are harder and stiffer I'd be inclined to compare with a sample of bass wood. Just being nosey but I tend to classify the wood (and junk I collect) as "potentially good for" and if bass wood is possible then I've got a nice straight piece that I collected from a storm felled tree that I've mostly used to carve spoons and such (imparts no taste and easy to scoop out with hand tools) - it's one of the woods I use to "nervously" whittle as I watch a video movie taking pieces with splits unusable for other purposes and convert them for fire starting - tilia will curl a really nice long chip with a sharp blade with almost no effort and while it can take great detail I can't imagine it surviving as part of a dovetail joint.

Rob

[Ned Knepp]

Hi Rob. I'm not sure that it is bass wood. It seems to cut a lot like it and the grain is very even. Color is white. I suppose it could be popular and I can't say about alder but it's not birch. I had to pull the finger board to fix a problem with the steel rod. Only part if it was really glued down anyway but that part was stuck tight. I worked it off with heat and a separation knife but some of the wood on the neck separated in to something like thread and had to be straighten out and glued back down. It was strange.

As a neck material, it leaves a lot to be desired and I'm sure it would never have held string tension for any length of time if it were not for the steel rod in it. If I can get a decent picture of it. I will post it. I want to put one or two showing the binding anyway.