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Okay, so I was going great guns on the Lefty SJ...it's a proper box now, and I was rough setting the neck angle...figures that I have a pretty good fit on the cheeks of the heel right off the bat...so, I'm jazzed about that and I put a straight edge on the f/b which I've taped to the neck (no frets)...problem is, over the bridge (also taped into place) I have 3/8" of airspace! Now, my question is, if I take enough off the heel at the top to bring that level to the top of the bridge, how to handle the inevitable gap at the 14th fret over the body...any help out there? TIA.

Larry

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   You need to take off at the top of the heel. The about you need to take is slight. I don't think that will be all that noticable. I do have had to do such things in my early days.
    If you have the frets off the board , I like to see about 1/8 or so . Once you fret the neck and you can adjust this by setting the neck and then prelaoding the neck by using about 5 lbs of weight on the shoulders of the guitar. Set the neck straigt by adjusting the truss rod. You now have your neck is position as if it were strung. You now can figure where the action is going to be and where the finish saddle height should be. Now you can adjust everything to this action.
    As long as you are 1/8 to 3/16 of saddle showing you will be about perfect.
   john

You can calculate how much you need to remove from the front of the neck with the following formula.

x = (a x b) / c

here is the definition of the variables.

x = the variable you are solving for, in this case the amount of material you need to remove from each side of the front of the neck.

a = distance the straight edge needs to move to be positioned in the CORRECT location. I want my straight edge to give me about 3/32" clearance, but your construction may call for something else. So you would need to take your current 3/8" and subtract off what your goal height is.

b = depth of the guitar at the neck join.

c = distance from the centerline at the top of the guitar to the saddle location.

This will work like a champ.

As to your 14th fret missing the top of the guitar. I have been faced with this problem before. If it is more than the distance of a fret, I usually build a new neck -- but understandably this is an extreme solution.

Brock Poling38600.7015393519

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Brock Poling
Columbus, Ohio
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Larry, since you still only have the board taped onto the fret your 14th fret will line up with the neck joint, no problem, your nut will be slightly smaller which shouldn't be a big problem unless of course you have to remove more than 1/16-3/32 from the top of the heal (assuming your using a nut which sits between the fretboard and the headstock veneer, not a nut which just sits onto of the headstock veneer and the fretboard butting up to headstock veneer). Otherwise, as Brock suggested, you may have to make a whole new neck.

Is this guitar for yourself or is it for a customer?

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Brock, I understand the formula but the 14th fret gap I was speaking of is in relation to the bottom of the f/b extension as relates to the top of the guitar above the soundhole...if I remove stock from the upper areas of the heel cheeks to shift the neck forward, I'll have a gap between the f/b extension and the guitar top at the body join....or am I making something out of nothing?

Larry

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Oh, and Brock...is "b" the total depth of the guitar top to bottom or top to bottom of the heel itself?

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Ah. Sorry. I mis understood your question.

b is the total depth of the guitar.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Rod, it's a customer's guitar...I did think to leave 1/16" of heel in front of the 14th fret for adjustments...so the actual body join will be at the 14th fret no problem...the thing that's worrying me is the gap I'm thinking will be at the body join between the bottom of the fretboard and the guitar top...

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Oh. Sorry.

You dome your tops I assume or at least cut an angle from the front of the soundhole to the head of the body. If you normally do this, and you've only had to adjust the neck, than you shouldn't have a gap between the bottom of the fretboard and the top of the body. If you do, than something else is wrong.

This is just my opinion of my understanding what the problem is.

Anyone else?

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Rod, I'm probably just thinking too much...I'm gonna take the old grinder to it this week and see what happens...(okay, I don't really use a grinder...just some 180 grit)

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I am getting a little confused as well...but...why can't you just make a taller bridge?

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

Larry, as you set the neck your saying that the plane of the bare FB is 3/8 proud of the top of the bridge. If I read you right.

Dependent on the back angle you have set the neck at brock is right. a small adjustment in the heal will make big differance at the bridge.

The thing to remember is that the point of rotating of the neck is the bottom of the fretboard at the joint. so if you lower the plane of the fretbord you may find that you need to remove material from the bottom of the fretboard to make the required fb to top fit-up

Or!! after making the adjustment to the heal, let the FB bulg up and relevel the fretboard after fitup. I had one I had to do this way all worked out fine. In fact, I have stopped freting till after neck is attached so that I can re-level the fetboard as a means of fine tuning the the set.MichaelP38601.4868865741

Ah Michael, you understand me! I'm a product of the Alabama Public Education System circa class of '81...they hadn't worked out all of their teaching issues back then...so, nowadays I pay for it with my lack of ability to articulate what goes on inside my head! As I told Brock, I'm probably overthinking this and it may not even present a problem...I've never had to remove material from the bottom of the f/b, so if I do what should I look out for? I suppose I need a clean "no crossing" line at the 14th fret...how about double-sticking sandpaper to the extension area above the soundhole and "lapping" the f/b bottom on it? I like the idea of just releveling the f/b before fretting...then the worst thing will be just deepening the slots from 15 or so on....

Larry

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I think the best method is to allow the FB extension to bow at glue up. Then re-level and deepen the slots after re-leveling. I deepen the slots with a 6" scroll saw blade by hand. I find I have a lot less trouble re-leveling that releaving the fb extension bottom.

I thought you articulated your proble just fine But then again I am a product of North Louisiana school system so that may tell you something

Thanks Michael, I'm gonna go out now and do it...I'll let you know if I return with a guitar or a well-shaped piece of firewood!

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Okay, I'm in! Seems to have worked fine...I'll post pix when it's done! Thanks for all the help guys...

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COOOOOOOOOOOOOOOOOOOL MichaelP38601.6433217593

Glad to hear it Larry

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