experimental semi-scarf joint (and frets w/o fingerboard!)

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Permalink Reply by The Phrygian Kid on July 22, 2012 at 10:33pm

Yes good one. I been doin body end scarf joins for some time. Jay from tiny guitars has done a few too. I've made no secret of it but few have followed.
See my reply to this. http://www.cigarboxnation.com/forum/topics/wrapping-my-head-around-...
For a shim inside the box I just use the bit of box that I cut out for the neck thru, cut it in half, one for each end. I been promising a bloG on it forever but im a lazy bastard.
Well done, great thinking

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Permalink Reply by Jim Woods on July 23, 2012 at 6:55pm

Looks good,

That should be plenty strong enough.  I have done a similar joint on a couple & I guessed if I have a 2" long joint, it will hold up to anything it needs to.   I like the little notch, since on mine the heel was a full 3/4" down.  I may steal it for the next one.

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Permalink Reply by TwoShoes on July 23, 2012 at 7:01pm

As long as that weaker corner does not prove to be a fatal flaw, there may be additional benefits!

A few more photos to show that the neck portion inside the box takes (much !?!) less work.

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Permalink Reply by The Phrygian Kid on July 23, 2012 at 7:25pm

That's almost exactly how I do it bravo!!
Except I run the join pretty much the entire length of the box. You have pitched your neck very steep IMHO. Great job. For those two little shims I use the little square I cut from te box cut in half

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Permalink Reply by TwoShoes on July 23, 2012 at 8:54pm

PK,

Your pics (and that blue line illustration I stole from one of your posts in particular) were my inspiration!  All I did was try to figure a way to head your overall direction but also eliminating some steps.  Your long scarfs are WAY stronger, but I was quite impatient smoothing the cuts!  

(Also... I don't have a band saw; I had a little trouble controlling my jig saw; and my scroll saw was working REALLY hard in oak.  A shorter angle cut was very attractive.)

The spacers are all you, too.  I just used a little leftover fingerboard scrap, but I like the economy of using the cut-out box side.  Waste not, want not, eh?

This is a banner day for me!  You know I've been stalking you, but now you've given me an "atta boy!"  I may swoon.  ;-)

Seriously, though... thanks for the thumbs up.

PS

Neck not so steep.  Close to 12°.  Bridge on the Punch build was 1 1/8" tall.

(I know you don't measure or calculate, but I had to set the bevel gauge to something and I just couldn't stand a "looks about right" without knowing!   Oh...and I love trigonometry, BTW!).

Cheers!

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Permalink Reply by Bluesheart on July 23, 2012 at 7:07pm

I think that is an excellent technique!! Thanks for all the good pics too. Gonna be trying that. I like being able to have a taller and or adjustable bridge and this seems just the ticket!

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Permalink Reply by ED (Bad Finger) on July 23, 2012 at 9:16pm

Approx how tall is the bridge?

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Permalink Reply by TwoShoes on July 23, 2012 at 10:12pm

On this, the first complete experiment

     http://www.cigarboxnation.com/photo/punch-alt-neck?context=user

the bridge is 1 1/8" tall.  

I've noticed that my bridges, which I do last (just like my Phrygian mentor!), are right around an inch.  I'm thinking it's because I've (arbitrarily) locked my bevel gauge at 12° and stick to a 24" scale (because it matches my 24" English/metric steel rule!).

PK pointed me to the Red Henry bridge blog

   http://www.murphymethod.com/index.cfm?event=pages.content&conte...

and I have to say I quite like it — even my poor attempts at knock-offs.

The tall bridges places strings well above the sound board, so us no-talent knuckle-draggers don't add a drum beat on every downstroke.  I hear that people who can play enjoy the extra room, too.  You'll have to ask them why, though.  0.o

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Permalink Reply by The Phrygian Kid on July 23, 2012 at 10:22pm

Good one. There's some reAl science in the red Henry bridge, I really like the way the guy shares his knowledge and publishes other peoples experiments there too, open source.

Next step... (respectful suggestion :D) get that nice tall bridge BETWEEN some sexy f holes. Dont follow the pack and let em creep forward!! For a real pro look try to get the pointy things midway pointing at the bridge like on a violin ;) get that right and you got about the loudest and best from a neck thru cbg IMHO ;)
Great work how many frets are you doing clear of the box?

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Permalink Reply by ChickenboneJohn on July 26, 2012 at 2:39am

I may be missing something here...but why are you introducing the notch rather than doing a simple scarf to get the angle? I know it sort of works, but it just seems unnecessarily complicated and more difficult.  You are cutting 25% out of the thickness of the neck end, thus weakening it at the greatest point of stress, and the glue joints I see are really thick - a glue joint ought to be virtually invisible in order to be strong. A simple scarf would be easier and stronger. To introduce some angle it's much easier to just glue the pieces together with no angle and taper the part that goes into the body..or do what I do - don't put any taper on the joint, screw the neck to a block running down the back of the box and use shims to introduce an angle.

Heres an illustration...the top two are the was I typically do it. The lowest picture shows a simplified version, but I always prefer to keep as much 'meat' in the end of the neck by extending the joint into the box.  These give you a nice simple joint, and keeps the thickness and strength where you need it most. The key point is maintaining continuity, that's why it's better in my opinion to extend the neck well into the box as single continuous pice of wood, keep the notching and cutting to a minimum, and ensure there's plenty of glueing surface on any laminations and joints.

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Permalink Reply by TwoShoes on July 26, 2012 at 9:03am

Chickenbone,

Well, my face is a bit red because you've got called me out in a couple of spots where I deserved it and possibly poked an Achilles heel that will take money for me to adequately cover. It will just have to remain exposed until I am better heeled.  =D

It is silly to defend a weakness, so I I'll gladly admit them. But how should I answer direct questions without avoiding or sounding defensive (because I dont ~feel~ defensive! :-D )  Point by point then?

> I may be missing something here...but why are you introducing the notch rather than doing a simple scarf to   > get the angle? I know it sort of works, but it just seems unnecessarily complicated and more difficult.

Lack of the right tools, Dude! Compounded by a lack of patience, of course. I don't have the cool setups some of the guys have shown, so I wanted to shape less wood. And since I was going experimental, I decided to eliminate the fingerboard, just for giggles.

ALSO... those short frets in the first picture were also an experiment. I cut to length and knocked the sharp ends off on a belt sander before pounding into slots. Proof of concept. Less ugly than the marks I was leaving with the file, but still unsettling.
NOTE: I've seen $tew-mac and the DIY tools and jigs. I already have a wish-list + a to-do list.

> You are cutting 25% out of the thickness of the neck end, thus weakening it at the greatest point of stress,

Acknowledged from the get-go. Dead on.

> and the glue joints I see are really thick - a glue joint ought to be virtually invisible in order to be strong.

Uh-oh. Really guilty here. I hyperfocused on knocking it together and let a hairline join fall to the wayside. On the upside, it created greater visibility in the photos! It's a feature, not a bug!

> A simple scarf would be easier and stronger. To introduce some angle it's much easier to just glue the pieces  > together with no angle and taper the part that goes into the body..

Ah, there's the rub! I was on the "stronger" bandwagon from the start, but easier?... Tools and shop setup! Remember how I departed from the map? I was exploring certain sacrifices to fit my methods to my means.

> or do what I do - don't put any taper on the joint, screw the neck to a block running down the back of the box  > and use shims to introduce an angle.

WHOA! I like the heck outta that shim approach! Thanks for the pics. The shim for the bottom is simple enough.  How long do you typically make the notch removed from the top?  I fear it could put me back in the long cut business. <sigh>  (More like long-time-with-hand-rasp-and-why-isn't-this-flat-yet business)


> Heres an illustration... <SNIP for space>

I guess my only philosophical leftover is NOT to disagree about what is stronger or better ('cuz I don't), but to wonder how far I can move from "stronger." Somewhere inside of "failure" plus a nice margin is "strong enough." Yes, good enough is the enemy of the great, but I think it may be another of those trade-off sliders that I see mentioned all over the CBN archives (you know... like the ones where Oily posts pics from the Les Paul museum to illustrate! Thanks, Oily, most helpful!).

Man, I really appreciate your input!  I have been semi-stalking you, but am now moving you up my list.

OH... if my experimental joints fail, I'll post to this thread. Uh...unless it takes 5 years or something. Who knows where we'll be!

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Permalink Reply by Ron "Oily" Sprague on July 26, 2012 at 11:35am

This is an interesting and fruitful exchange. On the one hand, you have an experienced builder who has fathered hundreds of guitars, builds customs for Hollowbelly, does workshops, and has his own gig going, offering solutions to a - I hesitate to call it a problem - perhaps design challenge?, that he has developed through experience. On the other, you have a less experienced builder, trying to solve the same challenge, coming up with his own solution, having it both validated by others, as well as questioned.

Dunno why, but this makes me think about two different things:

1) The original CBG builders ( and many others since) simply stuck a stick through a cheap box, added 1 or more wires and peg tuners, and made music with their creation. A look through the National Cigar Box Museum reveals lots of solutions to the attachment of neck to box. None of them that I have seen from the online pics appear quite as sophisticated, with the exceptions of the cigar box violin fretboards, as what is being discussed here.

2) The solutions presented here have been developed numerous times, sometimes "famously" (why I occasionally repost the pic of Les Paul's Log for illustration of one, not the only, way of doing things), by commercial builders the world over. Both builders here make valid points: ease and economy of design and construction vs. limitations of tools and technique. As it appears is happening here, the exposure of these techniques will provide food for thought for the full spectrum of builders.

I certainly learned some things from this discussion. Maybe this is an example of crowd sourcing and convergent evolution...

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