Beware ! You're in Kamikazie here. Not many pro luthiers around, more often brave souls experimenting in their kitchen.
H1203 Sovereign Neck Reset
Bluelick : I have a nice old 1203 Sovereign that I got at a yardsale more than ten years ago for $10. The sound is lovely but the action is terrible.
A friend who is a luthier suggested I tackle the reset myself. After reviewing the Kamikazie Luthier page here, frets.com and other sites, I bought a cappuccino maker and iron at the local junk store ($5.00 total) and went out to my shop today. We got 6 inches of snow overnight so today was a good day to spend in the shop! I spent a while cleaning up the workbench (always the first step) then rigged up my steaming rig. Finally, I was ready to come back to the house, read the online directions one more time, and take the 1203 to the shop.
Everything went as described. I did smoke a dot on the fretboard with the iron, and getting the fingerboard extension off was really the hard part. If I was doing it over, I'd get some thinner tools to get under the fretboard extension. I also think I was having trouble getting it hot enough as I was concerned about damaging the binding on the neck.
I also had a bit more tearout on the fret than I would have liked. Well, it's my first one. I saved the big chunk to re-glue in.
The neck came off in just seconds with the steam needle inserted. Here is the clamp system I used to get it off, with very little pressure:
I was surprised to find only one little wisp of a shim--of course, that may be why I'm having to reset it. The joint, now that it's all cleaned out, is quite loose, so I'll need to build a good bit back with shims. That's tomorrow.
Total time was three hours from when I took the guitar out to the shop until I had all the glue cleaned off the joint. I found a tip on this site about using the steam needle to soften and clean glue out of the joint--a great tip !
Next step, I put the neck on dry, pulled it back to where I want it (straightedge across the frets is touching the top of the saddle). I'm figuring the top will belly some under tension, so I'm starting out with the neck back a bit farther than where I want to end up (straightedge kissing the bridge). Besides, if I need to raise the saddle some that wouldn't be a bad thing either. I'd rather have the neck a bit too far back and adjust the saddle than end up with it too far forward and be back where I started. Any comments on this notion would be welcome. I'll clamp it together and string it before glue up to make sure it's right under tension.
I measured the gap between the neck and the body under the fingerboard, which was about .060. I think the whole body has moved a bit where the neck joins the body, part of why it needs the reset, and I'm guessing that is why the gap is so big. The top is sunk in slightly between the soundhole and the dovetail notch. Comments on that analysis are welcome also.
I have scribed a line on the neck at .060 with the neck fitted to the guitar. I plan to undercut the neck with a small chisel and then to the fitting by sanding.
fanfab4 : For you first try I think you did a fine job. :cheers: Before you steamed off the neck did you tape the surrounding areas ? I especially like the clamp system you used to get the neck seperated from the body . You seem to be going in the right direction. Good luck with resetting the neck. Look forward to the continuation.
SKP : wow...you jumped in with both feet! It's great seein' people try these procedures for the first time. I still have to do one. Haven't had too much time to roll my sleeves up and get into it yet... but thanks for posting pictures...inspires me !
Bluelick : Thanks for the encouragement, everyone. It was a good day in the shop..
Here is the gap and the scribed line for removing material (.060) from the heel:
I also had to repair the top where it was loose from the neck block and cracked:
Here's how it looked inside. It was great to be able to stick my digital camera inside the guitar!
I mentioned earlier that the top is sunk in a bit between the soundhole and the neck:
But, the brace seems to be tight and intact, so I decided to live with that and just fix the breaks. I put Titebond in the cracks and crevices, then used my airgun to blow it in and through the cracks, an old trick from my days building cabinets. Clamped it up and set it aside:
While the repair was setting up, I worked on relieving the neck so it would be ready to fit to the body. A rounded-end carving chisel was good for really digging in on this.
After a lot of pulling strips of sandpaper, I was close to the scribed line.
A couple thing were very helpful with this. First, I saw somewhere online the idea of backing the sandpaper with packing tape, which worked REALLY well. Second, and I think I came up with this on my own, putting the used strips of sandpaper in the dovetail notch as temporary shims worked well to fit the neck as I went along. I put the sand side toward the body and the slick tape side toward the neck. Taking up the extra space in the joint helped me see how I was doing, and the sand side kept the temporary shims from moving around while the slick side made it easy to get the neck in and out.
Finally, I strung up the high and low E strings and tuned them up to see how things were looking. Not bad !
By the way, I spotted this brace that need to be reglued. it is loose for about 1/3 of it's length, and the last inch or so looks to be split rather than just come loose at the glue joint.
Any input on process for this will be appreciated. I'm wondering if it's worth trying to sand under it to get old glue out or just use a strip of paper to work glue in under it and clamp it down. Sanding could make the glue joint looser, but removing old glue is generally a good thing. Thoughts on this ?
Snapcase : Herre and there
François : For this loose brace, if you use hide glue, I'm not sure cleaning old glue is necessary. But if you use white titebond it may help.. Just removing big bits of dried glue, to avoid one of these bits moving in the joint and avoiding a good contact...
I followed Snap's links and.. Wow, the stewmac "scissor jack" looks like a very nice tool for working inside a guitar... I wonder if it could go through a Harmony archtop f-hole. $90 is a bit excessive though...
I had made a "poor man scissor jack", not as easy to use but it worked for me
Bluelick : When I showed the 1203 to my friend the luthier, saying "What do you think?" she replied "Looks like an old guitar." Later she said "That's the perfect guitar to try a reset on" as in it wasn't (in her estimation) a very valuable one. Honestly, if I had valued it more highly I might not have tried this. I had decided that I would either get this one fixed to be more playable or I was going to get another one, since I couldn't stand to play it for more than a few minutes at a time. So, the prospect of fixing it myself just made sense--much more sense than spending hundreds of dollars on a $10 guitar. As I've gotten into it, I have come to appreciate this guitar a good bit, things like the quality of the wood, details like the multi-layer binding. However, I am also seeing the nature of the manufacturing--and this guitar was manufactured, not "built." The neck joint was machine made and doesn't seem to have had any further "fitting" other than a slender hunk of wood stuck in as a shim. I doubt that it played particularly well even when it was new. However, I think that with a decent amateur reset and set up, it will play well and should sound really good also, given the aged wood. I think it is going to be the perfect pond guitar, one I won't have to worry about, but that I can really enjoy playing and listening to. Well, that vision is still a few glue joints away !
But to anyone out there considering doing something like this, I'd say dive in! Work on that old guitar that you aren't playing. I do have a good woodworking shop but the only tools I've used on this are simple hand tools and the stuff from the mini-mall (cappuccino maker and iron). What's made it possible is all the good information online and in boards like this. So, thanks !
Zhyla : Always good to see someone get their feet wet with a neck reset. As you've found it's really not the hardest thing to do. I think it gets a mystique because of how much a pro neck reset costs. Obviously there's potential to really screw up your guitar, but looks like you know what you're doing.
Regarding the top cracking over the neck block... I think that's just due to needing a neck reset for so long. To really correct it I think you'd need to remove the piece that sits on the neck block and shim it up just right to be even with the rest of the top. Otherwise it's going to crack again when the string tension stresses the top. But who knows, might be fine, and either way it's not a huge structural thing.
Bluelick : I got back to work on the guitar in earnest this weekend, and have made a good bit of progress but I would like some feedback at this point. First, I decided to add the shims to the mortise of the dovetail since I thought the neckblock didn't present a great surface to work with on fitting the joint.
So, I began by cutting some angled cauls on the tablesaw. These worked out to be 27 degrees.
A pencil and a couple of sockets worked to wedge the cauls to glue in the shims, which are walnut veneer. My trial shims indicated that I needed about .046 at the top and .030 at the bottom on each side. In this picture I'm dry fitting the setup prior to gluing.
After adding the shims, I had a lot of fitting to do:
I did some filing on the shims to make sure I had a good flat surface.
A bit of careful filing on the neck, using chalk to see where it was rubbing, began to bring the neck into the joint.
However, the dogs were getting restless in the shop, it was after dark, and they wanted to be curled up by the fire. So I brought everything inside to continue the slow work of chalk, fit, sand/file/scrape, and repeat. And repeat. The dogs were right--sitting by the stove for this was much nicer !
Finally, and somewhat suddenly, it went all the way in. However, when I strung it up, there was a little gap at the heel (.012).
However, with no glue or clamps, I was able to string it, bring it up to pitch, and play it. As you see, the straightedge falls below the bridge with tension on (it sits just below the top of the saddle with the strings slack).
I have the truss rod just snug, so the neck relief gap in the middle of the neck is .002 slack and .007 tuned up. At the body, the string clearance is about .120, between 7/64 and 8/64. According to my math, bringing the heel gap in should drop the action another 64th or more.
So, here's my question. Should I try to do some more shimming to bring the heel in under tension, or is this what I should expect it to look like without being glued? I'd like the action to be really low, and I do expect to raise the nut just a tad, so I might even need to set the neck back a tad more. I'd appreciate any advice you all can offer before I go ahead with gluing it up.
Seems like a good time to pause and seek input. Besides, my fishing buddies are coming over to watch the Super Bowl this afternoon. We're not all that big on football, but we are always open to good reasons to get together for frosty adult beverages and good company, and it's too cold to go fishing !
François : Thanks again for the detailed report.
I have to say first I have no direct similar experience but I have read a lot about resets...
If you're after a really low action, you should get it before glueing.. If clamped right, the glueing process should not lower more the action... And after some time, you can only have a higher action, not lower (as reported recently by Lisa, for example). In the worse case, if action is a bit low after glue dried, you can always use a higher saddle, but if it's too high... In doubt, I would go for the lower action option, because it can only go higher with time...
If I remember well, Laurie (rlspt) did the same, ie strung it up to pitch before glueing, perhaps he could speak from direct experience...
Carl Croce : Your photo of the gap tells the whole story. You need that much more shim to get the heel cheeks tight up against the shoulders. Note the length and angle of the taper and the size at the bottom. That is your target shim profile. It will be slightly longer and larger than you need because the dove tail doesn't extend to the bottom of the heel, but that gives you the extra you need for fitting.
Bluelick : Thank you Francois and Carl. I agree, Carl, that I need to do some more shimming, and maybe even take some more off the heel to get the action I want, and that the gap at the heel is related to the thickness of the shim.
However, I believe that the geometry of this joint is such that the thickness of the shim will be less than the gap at the heel, but the formula for that kind relationship is long gone from my brain. I *think* it would be the length of a line that is perpendicular to the hypotenuse and bisects a right triangle of which the long leg is .012 and the acute angle is 27 degrees, and that kind of calculation went south for me a long time ago! What I can do is draw it at 10x or maybe 100x scale and measure it.
Or maybe I'll do it more empirically, like try a little shim and see how it fits...
See, this stuff just makes my head hurt!
François : In your triangle drawing above, I believe the 'shim' length your after is .012 x sinus 27° = 0.012 x 0.454 = 0.005448
tadsworld : I flunked algebra... twice.
Isn't music supposed to be math!?
Carl Croce : My father and grandfather were artists. They were both stonecutters. A stonecutter is a sculptor who works in granite or marble. They designed and made free standing and relief hand cut granite monuments. I have said before on this forum that, my dad was also a guitar player and a singer. Stone cutting was his day job. I used to work in his studio and stone shop weekends and summers growing up. He taught me drafting and how to cut stone figures and lettering using hand and pneumatic chisels and the sandblast machine. Sometimes when he saw me trying to be too intricate on a drawing he would say, "Come on, this is stone cutting not rocket science.", or, "We're not designing missels here, we're drawing a monument. It does not have to be so exact.", which brings me to the point of this post.
The geometry is all well and good, but in the end you are going to fit the final shims with chalk and a file. And remember, you'll be using two shims to keep the neck centered. You need not worry about being so exact. Close enough is close enough at this point in the job.
rlspt : i have never even tried to apply math to my neck resets. i got a headache just trying to follow along. my approach is more like, "well, let's see, i want that part to go down, so i have to take some off here and add some there, so i'll file this off a bit and then stick this wedgy thing in here and see what happens. shoot, that's wrong. okay, maybe if i put something here and file this off....well, that's closer. maybe if i do that again i'll...oops, too far, okay, let's back up and......"
i am in favor of getting the joint right where i want it, with a reasonably tight fit with firm wedges glued in place, before the final gluing together of the neck joint. i want to rely on solid wood-to-wood contact for all the strength and resistance the joint needs. the glue's just to keep it there. i often set the joint dry and string up at least the high and low e strings to confirm the action before i glue.
and i'm with francois, eventually the neck is going to rise again, so putting up with a tall saddle for a while is better than resetting the neck again sooner, so i'll go slightly past ideal action and expect to have to lower the saddle as time goes by. "slightly" is defined by you, but a saddle that's a fat 1/8" taller than you'd normally see ain't the end of the world and still works. i looked back at your pictures, it looks to me like your saddle is about down to the nubbins- i'd put in a new saddle, for better guaging of the action, before final gluing of the neck.
looks to me like you're doing great, i wish my first reset had gone so smoothly.
incidentally, it never occurred to me to wedge the sides of the dovetail as opposed to the plane where the butt of the dovetail meets the neck block. i'd always assumed the physics of the situation dictated that was where the rubber met the road, so to speak- the critical juncture where firmly wedging the gap there was going to do most to prevent the neck from coming up. does your joint have a space there?
so you math wizards and physics professors, what about this? does it matter where/how you wedge the joint? what's best? why?
Carl Croce : Yes, Laurie, all the luthiers I have asked have told me the wedges go on the sides of the dovetails. The object of that is to get the cheeks of the heel to press hard against the outboard flat surface of the block and the shoulders of the rims. This creates tension pulling the solid dovetail and the cheeks of the heel which is a single very strong part of the guitar, and a balancing compression force on the dovetails of the block making them stronger. This is one of the reasons to relieve the dove tail of the neck with a rounded chisel or auger: the rounded surface is stronger and more resistant to cracking. If you place the shim between the flat inside surface of the block, and the flat end surface of the neck tennon, you are creating an unbalanced compression force which pushes the cheeks of the neck away from the block and shoulders, and which may cause the dove tails of the block to crack outward. It may be tight, but won't be as strong as shimming the dovetail mating surfaces.
rlspt : so carl, what if you do both- if you wedge the sides of the dovetail against their respective mating surfaces of the neck block as well as wedging the butt of the neck against the neck block? is that theoretically a stronger or weaker joint than just the sides?
that's always been my approach- to wedge the dry joint tight in every direction it might try to move in response to string tension. is that creating stress somewhere/somehow i hadn't thought of?
and what are the pros and cons of gluing the wedges to the neck block or the neck itself? does it make any difference?
Carl Croce : In the sense of which way it will make a better joint, it doesn't matter, Laurie, whether you glue the shims to the neck dovetail surfaces or the block dovetail surfaces, because the shims will be glued to the mating surfaces of both the block and the neck tennon in the end. It is more a matter of how you want to fit the parts and what is easier to clamp the shims to and file them on during the fitting. I have seen articles describing gluing the shims to the block, and the guys I have talked to who do this all the time do it that way. It is easier to work on if the shims are in the block.
In terms of both shimming the dove tails and shimming the head space between the end of the neck tennon and the interior flat surface of the block, that is not a good idea because shimming the head space will push out the neck so the heel cheeks do not contact the shoulders and the exterior flat surfaces of the neck block strongly. It will cause the interior dove tail surfaces of the neck block to deform, so the mating dove tail surfaces you have worked so hard to fit will only mate at the outer edges of the neck tennon and open up as you go toward the relief grove, and if too much unbalanced compression force is applied the sides of the block may crack. Actually, Laurie, you are the first person I have come across who has suggested doing that.
François : About math and physics, at school I've always been good in physics, and bad in maths. Physics have direct applications in life, so it's easier to see why you should learn some... With age, I see things differently, if physics can help you to hunt, fish, or... reset necks, maths can give some clues about the meaning of life. We're too young at school to do maths.
I think it's good to find the best, ideal, theorical neck reset technique, but in real life I'm not even sure that filling all gaps with hide glue instead of precise shims would make any difference. Dry hide glue is very hard, even harder than wood, it will not compress under string tension (if it fills gaps of course). I believe that's how they made these guitars : the factory shims that we can find inside neck joints were there only to hold the things togeteher at the right place while glueing/clamping..
In other words, to me the Laurie toothpicks technique (photo below) is an easy and efficient way, even if you just leave them in place without trying to fill the spaces with wood. But I would use them only on the sides, not on the flat end...
The dovetail principle dictates to shim inside the dovetail, not at the end of the neck. Carl has better words than me, I agree with what he said :-)
Bluelick : Greetings all,
First let me thank all of you for taking part in this thread, it's extremely helpful to me as a first-time luthier. Well, in all honesty it's not my first attempt at working on a guitar, just the first time I've ever tried to do it the right way. Once I get done with this reset I'm going to go back and see what I can do with my old Howard archtop (the one in the middle in my avatar picture of the three guitars). I'll have to start by removing the drywall screws...
I am a "seat of the pants engineer" by inclination although not by training. I have a background in construction and cabinet building, also have done a fair amount of plumbing and electrical work and just generally like figuring out how to do things, make things, and fix things. Living in the country, you learn how to fix things (mowers, chainsaws, outboard motors, etc.). If I enjoy using something, I want to know what makes it tick and I'll eventually take it apart! We designed and built our passive solar home. I built a hydraulic ram several years ago to pump water from the pond to the gardens with no external power source. Things like that. All that by way of saying that I enjoy figuring things out. The way my head works I will be trying to determine what the geometry of something like this neck joint is, but my approach in the end will probably be more pragmatic, just as Carl suggests.
Francois, I am truly impressed by your immediate grasp of the formula, and I thank you for that. I *might* have been able to do that 35 years ago. I remember the point at which I could no longer help my daughter with her math homework, it was a real eye-opener. That was when I first realized how much of what I had once known had slipped away. On reflection, I wouldn't trade what I've learned for what I've forgotten. But I digress.
I am thinking that the next phase of this is going to involve some pretty fine tolerances, to I may try to find some carbon paper. I suspect that I have picked up stray chalk marks at some points while fitting and removing the neck that represented bumping the cheeks on the way in and out rather than the actual tight points of the fit. Any suggestions on that will be appreciated.
I have decided that (as several of you suggest) I will set the neck back just a bit further and raise the saddle--I need to raise the nut as well since it was filed down to make the first few frets playable when the action was so high. I would welcome suggestions on removing the saddle. It would be nice to get it out in one piece to use it as a template. I will at least scribe the curve onto something before I go at it.
rlspt : you know, i'd love to know how they set the necks at the harmony factory. i'm sure they didn't diddle around with each guitar for hours on end. they must have had some jig that some dummy threw the neck and body in and wham, it was done. how else could they have been kicking hundreds of guitars a day out the door?
and i'll bet they did rely on the glue to hold the set, at least to some degree. the neck joints were probably cut with some slop to them, and they relied on the glue clamping jig to hold things in place until the glue dried.
Carl Croce : I believe you are correct, Laurie, All the removed Harmony necks I have seen had small shims and a lot of hide glue in them, as well as the photos I see here in this section. Hide glue, which crystalizes harder than the wood was used libreally to keep things together where they belonged. After years of shrinkage (old wood does shrink ever so slightly and get harder with age) these joints start to move in their glue surroundings and the string tension pulls the neck angle up. And here we are now, many years later fixing these old girls up sweet and pretty.
Bluelick : Greetings all,
I have just come back into the house after gluing and clamping the neck. I feel good about it, and looking forward to stringing it up. I strung it and played for a while today with it shimmed but not glued, and it sounded and played great!
OK, here are some pictures of "the rest of the story." For starters, I sanded the heel to bring the neck a bit farther back. Now with it strung and tuned (shimmed but not glued), the straightedge sat on top of the bridge. With it slack, the straightedge sat on top of the saddle.
Then, I used paper to shim the neck into position. The allowed me to determine how think the wood shims needed to be:
I needed to thin the veneer I was using for shims, so I clamped it to another piece of wood and then put a piece of sandpaper face up on my table saw. This worked really well for tapering and thinning the shims:
Once I had the shims close, I would fit them, pull the neck joint down tight, take it back apart and look for shiny spots on the shims. Then I would hand sand the shiny spots, and fit it again. By the time I got it where I wanted it, this shim was getting pretty thin, as you can see by the light shining through it:
Finally it was time to turn off the radio, get everything laid out, take a deep breath, and glue it up. I put glue on the underside of the fingerboard, then the tenon, stuck the shims on the tenon, put glue on the outside of the shims and in the mortise, then put it together. As tight as it was when I fit it together dry, with the glue lubricating the joint it went together easily.
I made a caul for the fingerboard from a piece of plywood, cut the radius on the bandsaw, padded it with a few layers of shop towel, and wrapped it in packing tape.
I'm letting it rest overnight, then I'll be ready to string it up. I still need to re-glue a brace inside, so the only question is whether I'll be able to make myself do that before I get to play it. Probably not!
to be continued...
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