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I am at work so I had to send this to myself over the phone in small format because I can’t resize here. I hope this displays okay. Here is what the cap nuts Todd was talking about look like (in brass here) if you don’t hide them. Doing this with hangar bolts and these nuts is way too easy and doesn’t look too bad.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I countersink with a "reverse spotfacer" tool. All's hidden.

The KD nut is cool, but I dislike the little allen head and prefer using a standard nut and socket. The flanged nuts also have little 'teeth' on the flange/washer, that grabs into the wood of the neck block a wee bit, helping to prevent them from working themselves loose. During the setup, I'll use connector nuts, which are about an inch long, and can just spin them on and even just finger tight, I can string the guitar up and check the neck angle and alignment. Couldn't do that with inserts and KD bolts(which I did use for a few years).

But for sure, either way works just fine; it's just that I always go for the simplest method, as long as there aren't any downsides, and I can think of none here.

Mario, far be it from me to teach my grandfather how to suck eggs, but ...you do surprise me.

Are you saying that you tighten the (serrated) flange nut directly onto the wood of the neck block ?

Would it not be a better approach to have a flat aluminum washer in contact with the wood, then an internally serrated lockproof washer, then another flat aluminum washer, and then your flange nut?

That way, the wood doesn't get all chewed up by the serrations, and the pressure exerted by the serrated lockproof washer (and also the serrated flange nut) ensures that the assembly never comes loose unintentionally.

When it comes to neck reset time, hey...your wood is all pristine, ready to reassemble .

Or a meringue ?

Can you remove hanger bolts through the sound box for a flossing neck reset? Because that would be a huge disadvantage imho.

I'm glad you guys chimed in and extolled the virtues of hanger bolts. I truly am, because there will be more flat tops in my future. But I am currently obsessed with archtops and their f-holes or s-holes and I'm trying to figure out if a nut could be fished through an f-hole and secured to the end of a long, home-made allen wrench poked through the tail pin hole. Hmmmmmmmm..... Anyone ever tried that?

I've done it a few times. Very easy.

Are you saying that you tighten the (serrated) flange nut directly onto the wood of the neck block ?

Would it not be a better approach to have a flat aluminum washer in contact with the wood, then an internally serrated lockproof washer, then another flat aluminum washer, and then your flange nut?

That way, the wood doesn't get all chewed up by the serrations, and the pressure exerted by the serrated lockproof washer (and also the serrated flange nut) ensures that the assembly never comes loose unintentionally.

When it comes to neck reset time, hey...your wood is all pristine, ready to reassemble .


The flanged nuts aren't lock washers. They simply have little "ridges" in them, and yes, I put them right against the neck block and yes, they "dig" into the wood, but no, they don't do any damage because they're not aggressive(nor sharp) enough. My neck blocks are spruce or cedar, too.

And yes again, you can definitely loosen the nuts and floss the heel to reset the neck; I've done it on pretty much every guitar I build. Where most of you will fine tune the setup, after the guitar has settled-in for a week or three, by shaving the saddle a wee bit, I'll just floss the heel. Last thing I do before boxing-up the guitar for shipment is to place the label over the bolts; I don't place the label over them until that moment, just in case I decide to tweak it just a wee bit more.

Simple..:

If the label's messed up, it means someone else has messed with the neck.

Anyone authorized by me will be sent a new label to put in place.

I like this, and plan to steal it......twenty years from now when I get my first customer, lol.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

I have a flexible shaft ratchet driver that I used to bolt on an oval hole Selmer neck. It worked like a charm on the Selmer but it could proove to be an exercise in humility on an archtop. I did a search but could not find it, but anyway, some one (padme I think) did a thread last year on making a tool to get to the bolt on neck through the strap pin hole in the tail block.

You could also build a trap door, something that would prove very handy if you have electronics too.

We have had good discussions on reinforcing the Cumpiano neck joint several times in the past. This thread has some good stuff.

viewtopic.php?f=10101&t=31203&p=413582&hilit=carbon+cumpiano#p413582

My tests indicated that some type of reinforcement is a good idea. It didn't take much force for the tenon to fail in tension.
A carbon or maple reinforcing strip made it almost impossible to induce a failure. I use Maple now as it is easier on drill bits and gives excellent strength.

On bolt-on's for archtops there have also been several excellent threads on this if you do a search. I've done four, the oldest is out about three years and I saw it last year and it was holding well. I was a little nervous about it.

The Cumpiano method is excellent for archtops as there is a higher neck angle and the bolts can self align. They are easily accessible through the end jack hole with a long wrench. Put rubber retaining washers on the other side so they don't fall out of the headblock..
I thread a piece of rubber tubing through the headblock holes into the guitar and fish it out an f hole and use it to pull the bolt in place. You can see the rubber retaining washer in the last picture.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Dave Stewart also has a tutorial around here somewhere Filippo. I think I got the idea for the retaining washers from him.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

John, Todd, Mario, et al,
Sorry if I'm being dense here, but are you guys saying you have eliminated any mortise and tenon and instead are attaching the hanger bolts through the neck block and straight into the heel of the neck, creating a butt joint? Or was the photo below simply taken prior to the tenon being cut?

By the way, a tutorial on how you tackle this hanger bolt solution sure would be awesome!

George :-)

George,

That is a butt joint. No tenon at all. That picture is before the heel is carved but pretty much that is what is what it connecting to the body.

When I first did this, it felt like cheating, but now I’m sold on it.


John

Amen to that!

That's all there is to it. If you think this is a new and untried idea, well, Bob Taylor's built hundreds of thousands of guitars with the same simple neck joint and continues to do so to this day; their original neck joint was exactly what I use, a bolted butt joint with the fretboard glued to the top, but even their "new" neck joint is simply inlet into the ribs slightly to allow for the shims, but it's still a basic butt joint.

Wow. I guess I am really dense! Up until now I thought everyone was doing some kind of straight or dovetailed mortise and tenon, with butt joints being an outmoded method in guitar making. I knew Taylor had their own joint but never bothered to look into their process. I learn something new here everyday, which I think is great!

Thanks,

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George :-)

Brilliant Terrence!

If I'm following this correctly, even when doing a butt joint, some of you are using a hardwood dowel in the heel to give the hangar bolts (or threaded inserts) cross grain bite, as opposed to end grain. Is this right?

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George :-)

Correct. Not only to give the inserts or bolts something other than end grain to bite into, but because the heel area itself is now smaller(there's no tenon or dovetail) and it's all(or mostly) short grain, the dowel adds a large safety margin in the event of a fall or simply from rough handling. I cracked the heel on my original guitar some years ago when I, literally, absentmindedly tossed the gig bag into our van(I typically carry my guitar in a Calton case and can toss it at will...<g>). The dowel held the heel together and with just a bit of HHG and clamping the next day, it's been solid since then, with only a wee hairline to show for the ordeal. Without the dowel, methinks it would have been much uglier. Even if I were building with dovetails, I'd still add a dowel.

Fillipo where can I access the oscillating spindle sander jig to do a butt joint on my classical?? thanks

Thanks fillipo, PM me when you do, as I would like to print colour photos so I can make a similiar jig.Have a clayton spindle sander. Will be visiting houston next week regards ernie