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Permalink Reply by Bad Finger (Eric) on July 26, 2012 at 2:27am

This. . . I like this very much.  Another trick to add to the treats.  Thank you Chickenbone John for sharing the details.

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Permalink Reply by The Phrygian Kid on July 26, 2012 at 11:38am

Well it's easy to attack little shortcomings here or there but I think you've done great 2 shoes and I applaud your efforts. I don't do a buttressed scarf like that either (you'll often see this on old wooden bridges, usually reinforced witha bolt) but I can tell you for sure that it'll carry three strings for years without a problem. You would have got a cleaner glue join if you'd skipped the notch there. So what? At least you've taken in stuff you've seen (my stuff) and experimented with it and put your balls on the line and shared. Chookybones' approach there Is clever too but not necessarily more so, if you manage to get it in there without bracing along the back either (like I do) the benefits will be obvious when ur playing it and can feel te back singing along too. More power to ya. You know you've not mastered it but you're well on ur way. This body en scarf join was a quantum leap in my building when I worked it out a couple years back and I know you're proud of the difference from ur last few and wanting to share. Good for you.

CBJ - those'neck partway thru' diagrams are great!! But given that you extend that glue join inside te box I don't know that you really need such a massive heel on there? It's not all that different to what I do at all except I want to avoid te big heel so I glue along the whole length o the box and fix with screws thru the tail and into the end. Great ideas all around and those who dont see the value in a neck angle and a big tall bridge I'd encourage you to try it :)

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Permalink Reply by ChickenboneJohn on July 26, 2012 at 7:25pm

Glad I haven't upset too many people by setting-out my approach...after all, if it works, it's good.  To notch out the end of the neck to fit in the box, its just two saw cuts. A good sharp handsaw and a steady eye will do the job...these days I use the bandsaw, but as I said in an earlier post, I did a couple of hundred guitars with hand tools before I started getting any workshop power tools. As for handtools..good and sharp are the key words: a cheap, blunt handsaw will make things much harder than they ought to be. You don't need to spend a fortune, but when a tool gets blunt you need to sharpen it, or in the case of the budget handsaws, throw it away and get a new one.

The reason I often go for a heel that extends well up the neck is that notching the end of the neck to fit in the box (and notching it again to take a magnetic pickup) creates a weak point where the leverage on the neck is at it's most severe, so I try and keep a good thickness under where I'm notching out, and maximise the glueing area. I find that the heel doesn't really interfere with the fretting hand.  The heel stiffens the neck and effectively shortens the length that's subject to the bending stresses, making the whole thing more rigid, durable and resonant. I've seen many necks that have been notched to such an extent that this weak point acts as a hinge and the neck really starts to pull forward under string tension - that's why you need the extra thickness at that point, and it's important to extend that thickness well past the notch (by say, a couple of inches), as that is the point where the stresses are highest.  The larger glueing areas also helps spread the stress in the glue joint over a larger area, so it's more reliable, less prone to failure and more tolerant of inaccuracies in the joint.  Wherever the neck is glued or screwed to the box, the part of the neck 'outboard' of that fixing point is subject to the most severe bending forces (in engineering terms,  it's the root of a cantilever), so that's why it's a good idea to extend the heel to stiffen the 'root' of the neck. Past that fixing point and inside the box the stresses on the neck are different  -  if I didn't have the heel then all that leverage and bending would be exerted on the thiner part of the neck inside the box. 

By the way, those stepped or 'joggled scarf' joints on big timber structures are usually designed to resist tension (although they would also resist compression), as they commonly have a square timber 'key' inside the joint to stop the two parts sliding apart under stress. The bolts apply a clamping pressure so the parts bite down onto the key(s) in heart of the joint...it's quite a sophisticated bit of engineering.

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Permalink Reply by The Phrygian Kid on July 26, 2012 at 9:07pm

Ur a smart guy chookybones, I'm a fan

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Permalink Reply by Diglydog on July 26, 2012 at 9:21pm

Just spotted this. I have some bits of old seasoned oak that I thought were too short for a through neck, but they'll be fine like this. Thanks to TwoShoes for the pics and to ChickenboneJohn for the diagrams !

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Permalink Reply by ChickenboneJohn on July 26, 2012 at 11:48pm

One of the reasons I've built more "set in" necks rather than thru' necks is down to the length of the available lumber..."needs must when The Devil drives"...

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Permalink Reply by Michael Fred Johnson on July 29, 2012 at 12:23am

Like Chickenbone John I'm building fewer through necks.More with a simple joint at the body like this one. The neck angle is achieved by planing the neck top surface so 1/4" is removed at the nut tapering to nothing at the body.If you want a higher bridge lift the neck by adding blocks as in the Guinness photo

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Permalink Reply by Michael Fred Johnson on July 29, 2012 at 12:25am

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