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My neck is mocked up and I'm making certain my layout is spot on. I've added 2.2mm to the tenon so that the tenon will seat firmly in the mortice. I've got 87 degree slopes on the sides of my neck and will angle them inward 5 degrees to facilitate flossing when the time comes. Does this sound correct to you?

But here's this trussrod and I'm not exactly sure where it terminates? If I follow the Grellier plan the truss rod starts well into the headblock (less than 1/2) and the nut end of the trussrod ends about 3/8 AFTER the first fret. I "thought" the rod was supposed to extend to the middle (between the first fret and nut)?

No instructions were included with the Stew-Mac low profile truss rod. I am aware that a rounded, 1.5 inch channel needs to be cut at the adjustment end. But otherwise lost.

Do I unwrap the black plastic around it?

Flat bottom channel or rounded to match the trussrod profile?

Filler strip on top?

Silicone on bottom of channel?

Thanks for your help,

-j

I found these instructions on the Stew Mac web site:

http://www.stewmac.com/How-To/Online_Re ... s_Rod.html

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It will probably be alright.

Don't unwrap it. I don't think you need a round bottom channel either but you could certainly do that if you wish.

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Bryan Bear PMoMC

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

You sure about that ? The neck plane is angled down 3 degrees from the plane of the tops of the sides ? That seems steep for a flat-top guitar.

What sort of radius are you planning on making the top?

It's a 25 foot radius on the top. I'm following the Grellier OM plan and I measured 87 degrees for the heel. Maybe I measured incorrectly? I was tad confused at the 1.5 degree slope on the upper bout and 87 for the neck angle. Am I missing something?

Firstly, I'd really like to know where the truss rod should terminate. The stewmac website instructions are for an electric guitar. They show it ending at the neck which it could assume it should terminate at the end of my tenon?

Good call, I meant to comment on that and forgot. 1.5 degrees is more typical but the angel really will be determined by the radius of the upper bout and/or the planned bridge height/fretboard thickness depending on the build method you are using. You really can't just take the angel off the drawing (actually you should never scale anything off the drawing) it can get you close but you will need to adjust it to the body or build it in with a particular build method.

Decide where the adjustment nut needs to be with your neck joint and heel block arrangement and let the other end fall where it may. You should be fine.

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Bryan Bear PMoMC

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

Thanks, I didn't realize that I cannot follow the drawing. This throws a serious wrench in my plans. Because I'm planning on using LMI neck bolts (the type with the brass insert) I need to get the neck angle pretty close beforehand so I can drill the bolts square.

I'm a tad worried now.

Don't get too worried. I like to finish the box before I put the angle in the neck blank. That way I can get really close before I do the bolts. You probably have enough heel left to adjust the angle on your neck blank, just set it aside and work on the box. In the mean time read up on all the various methods of determining neck angle. The first few times you do it, it can be intimidating. It's just part of the growing pains you'll encounter and get over. Almost anything can be fixed and you usually learn something from the fixing. Just remember it is as easy to get ahead of yourself as it is to paralyse yourself with fear of proceeding. You just need to find a good balance, in the end you'll learn from doing (and sometimes re-doing).

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Bryan Bear PMoMC

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

Sincere appreciation for the tips and encouragement. I'll go back to the box now, which is whole other set of complications. Despite the perils I am enjoying this build.

For a 25' radius I used to use 1 1/2 degree on the heel as a starting point and then work from there (now I use Simpson jig that sets the angle for me). If the upper transverse is close to flat this usually works well. Point is, you're close, so like Brian said, get the box closed and do some measurements then you can do a final trim on the neck.

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Steve Smith
"Music is what feelings sound like"

Be sure the tenion does not bottom out in the mortise, the neck needs to rest on the shoulders. I usually leave at least 1/16" gap.

That's going to be too much neck angle, especially if you're tapering the heel down to 1" wide at the bottom. The 5° on the shoulders may be enough to get the angle you need, depending on how much you taper the heel. As the heel tapers, you get further from the original edge and the original angle. That's the method Cumpiano uses to get the neck angle, it starts out square.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

It would appear that I've got to just cut it straight for now and cobble the fitment to the box later. I foolishly thought I was doing good to advance the layout. I'm still a bit stressed about the bolts but that time will come. Thanks for the replies.