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Working on my first and trying to figure out the right neck angle. Somogyi says the neck (without fretboard) should be coplanar with the top. Kinkead is non-specific, and Cumpiano only deals with it with the fretted fret board installed.

I'm inclined to go with Somogyi (probably cause my neck's already coplanar with the top , but when I tape the fretboard and bridge on and check it, the straightedge bumps into the bridge, maybe 1/8" below the top.

(Note: The top is flat. I'm using an LMI pyramid bridge and an LMI pre-radiused fretboard)

As always, thanks in advance for your help.

Steve

Steve,

This is an area that gives a lot of folks trouble and sometimes takes several guitars to dial it in right for your specs.
Here is what I do. I set the neck anlge so that when placing a straightedge along it (no fretboard) the gap between the ruler and the top at the saddle location is 3.5mm I then make my fretboard about 6.5mm thick. With the fretboard installed on the neck (radiused and leveled) the gap between the straightedge and the saddle location is now 10mm. (3.5 +6.5 = 10)
I then make my bridge at 10mm (depending on the model guitar) I sometimes go a bit less but never more than 10mm tall. Once the frets are installed the end of the straighedge should just sail over the top of the bridge by about 1/32 - 1/16. This should give you the correct action with the correct saddle height when doing your set up.
Hope this helps.

First, before you panic, recheck the bridge location to be sure that your bridge is in the right location relative to the 12th fret. Check the neck with fingerboard with a straightedge, being sure that the fingerboard is clamped down to the blank, that the tongue is down against the top and the heel tight to the body. Also see that the surface is straight on the fingerboard. Now check the neck to bridge relationship. If its still low, proceed below.

In a perfect world, coplanar is great. Forget about what you'd like for the time being, and examine what you have and what you need.

For your guitar to play with proper action, with the bridge at the correct location, and the neck with fingerboard without the frets, you need to have about .020" clearance above the bridge without the saddle. The .020" combined with .043" fret wire (fairly standard) gives you 1/16" clearance above the bridge before stringing. The top will pull up and the neck will be very close to optimal neck to bridge alignment (frets tangent to the top surface of the bridge, under tension).

So if its still low, you need to increase the neck set a little at a time, until you get the relationship right. Don't pin the bridge location until you've got the neck set correctly.

Good luck.

Steve: Lots going on here. You need to know what height over the top you want your strings at the bridge. Think about .500 to .560 is good figure.When checking the angle with a straight edge it is best if your board is fretted,if it is not you can take that into consideration when measuring.With the board (fretted) and the bridge in place and your straight edge in place on centre line see where the end of straight edge hits bridge. Think this is what you have done already.With a bridge of about .375 to .400 the straight edge should be about 1/16" or so above the bridge.This is for a new guitar,for an older guitar that has been strung up for a while,the straight edge should just go over the top of bridge.This is what works for me ,see what some of the other folks say.I make the assumption you know how to modify the angle to get these approximate figures. Good luck.
Tom PS looks like David B. and I have said the same thing but in different words.

_________________
A person who has never made a mistake has never made anything!!!

Steve here is a toot explaining how I fit my necks AND set my neck angle. I know you are just interested in the neck angle portion but they are all related.
[url]http://www.luthiersforum.com/forum/viewtopic.php?f=10102&t=15022%22/url]

I hope this helps.

Steve-
The advice you've gotten in the four posts above is excellent. (I've printed it out for my files.)

I just wanted to add that in Somoygi's excellent talk/article reprinted in BigRedBook#4,394 (which you may have seen, or parts of this may be reprinted in Somoygi's book(s)?) he shows a 'neck alignment tool' for checking the neck angle.
For steel-string guitars, the tool shows the line of the neck without fingerboard should be touching the top at the bridge position. With unfretted fingerboard, the line should be 1/4" above the top, according to Somoygi-corresponding with a fingerboard thickness of 1/4". The 'coplanar' aspect shown in the diagram is a simplification, since most tops will have some arching. Steve- do you know what bridge thickness Somoygi is recommending in his book? His measurements would seem to demand a thinner bridge than many use.....

As Robbie, David, and Tom (and Hesh, while I was typing...) have pointed out (Thanks!) this measurement has to work with the planned thickness of your fingerboard, bridge thickness, desired string height above the soundboard, fret height, saddle projection, soundboard arching (and change in arching with string tension) and desired action at 12th fret.

It's a 'whole package' sorta thing and it's a good idea to draw a 'side view' on paper to get it all worked out.

It's a smart move on your part to be thinking this out now - some of us have found problems in neck angle 'later'- not insoluble (usually) but better to get it right from the start.

Cheers
John

Thanks everyone, that was hugely helpful. Now, off to floss my cheeks

Steve