Yet another neck angle question

[peachtree]

Hello everyone! I'm partway through the process of building a single cut and am ready to cut the neck angle into the body (/have already started). I *think* I understand conceptually what I'm trying to do, but I'm a bit confused about some of the advice I read/watch. In particular, I was watching this great video by Crimson Guitars: 

 

Ben seems to be laying a straight edge along the neck plane, compensating for the fretboard and width of a fret, and lining this up with the top of the bridge (with a couple of mm to give some room for adjustment). My question is - shouldn't we be allowing in room for the action also? That is, I want to lay a straight edge flat on the neck angle, and it should hit the plane that's perpendicular to the bridge at (the height of the bridge + compensation - (width of fretboard + width of fret + action)?

The setup I have is below (apologies for my crappy drawing). I don't know if it's obvious but just in case it's not, the drawing is supposed to be a cross section down the centreline of my body, with a straight edge (the notched rectangle) along the top. I forgot to draw it in but there's ~3mm or so between the bridge and the straight edge. I've started cutting my angle in at 4.5 degrees, which I think is wrong, given the below, but I've got 6mm of top still left to cut away before I hit my binding.

I have:

14mm bridge

6mm fretboard

1.5mm-ish fret wire

Given this, I think I should be aiming for my neck plane to intersect my bridge plane at 14 (bridge) + 2mm (wiggle room) - 6mm (fretboard) - 1.5mm (fret wire) - 2mm (action) = 6.5mm above the body. Do I have this wrong? Any other opinions very much appreciated 

 

[Crusader]

I personally never have any idea what angle my necks are on, I just go by a straight edge simulating the line of the string

Correction: It seems I go by the bottom of the fretboard, but initially go by the line of the string. Here's one of my crappy drawings...and a photo

 

 

What I actually do is take a ton of measurements from my Les Paul and just try to copy it exactly

This is a box I made to router the angle. I go by the distance and rise, so the distance to bridge is 252mm and the rise is about 8 or 9mm. Its an approach I've taken from roof carpentry

 

[Bizman62]

I share @Crusader's thoughts. Actually, I've never even measured the neck angle on my guitars! I've just used the method #1 Uncle Ben mentioned: Draw a full size picture either on paper or directly on the neck if it's a neck-thru like mine have been. The video you linked to is one of the early ones with less advertising, in a later one he used a hanheld power planer the same way.

Remember that any neck break angle is right! Well, not exactly, but any feasible one is. You have three pivot points: The nut, the bridge and the neck joint. The string always creates a straight line and you'll have to align the neck with that by creating an angle:

As you can see, there's some impossible options and some that are harder to play. The orange neck with the green string line is the goal.

 

[Bizman62]

I gave a further thought to the process and here's the result of my pondering:

• If/since you use a tall height adjustable bridge, take into account the collars of the threaded inserts of the studs. They add some 1.5 mm.
• For thicknessing the block for planing, take the combined height of your bridge and subtract  the thickness of the fretboard (including frets and the potential amount of neck you want to show above the body)

Hopefully this makes sense:

[mistermikev]

in answer to your question... sure.  you COULD factor in some mm for action... but you have already kind of done that with your 2mm of slop.  That said... if you lay out your items in a simple graphic editor like paint even... you'll find that there is a LOT more variability to it than one might first suspect.  esp if like a les paul... you put a pickup plane AND a neck plane in... you can literally make any angle (1deg to 5deg) work by just lowering or raising the neck.

getting back to what you are asking... I think giving yourself 2mm of slop is more than you need... and giving more you risk issues with the bridge sitting too high.  It's not enough imo to get it to work... you need it "not too high" and "not too low"!

EDIT: forgot to mention... you also may consider that the typical tom bridge - you are going to file down into the saddles approx 1mm for string grooves.

[Crusader]

On 5/31/2023 at 12:57 AM, mistermikev said:

... you need it "not too high" and "not too low"!

So true, I made my ES neck angle too low for a Tunomatic and too high for a bone saddle, had to make my own (intonation is not the best)

[peachtree]

Thanks everyone for the replies! I've stumped up the courage and below is what I have so far - I don't know if it's super clear from the pic but the fretboard laid across the neck plane basically comes in just above the bridge when it's sitting on the body (which is a clumsy way of saying a straight edge across the top of the fretboard extended over the bridge clears the bridge by 6mm, if it's just sitting on the body.

I think this is usable but probs not ideal - especially after frets/action etc my bridge is probs going to be sitting a little too high. I'll decrease the angle a bit I guess. Do you guys agree?

[MiKro]

3 hours ago, peachtree said:

Thanks everyone for the replies! I've stumped up the courage and below is what I have so far - I don't know if it's super clear from the pic but the fretboard laid across the neck plane basically comes in just above the bridge when it's sitting on the body (which is a clumsy way of saying a straight edge across the top of the fretboard extended over the bridge clears the bridge by 6mm, if it's just sitting on the body.

I think this is usable but probs not ideal - especially after frets/action etc my bridge is probs going to be sitting a little too high. I'll decrease the angle a bit I guess. Do you guys agree?

 

First off you have no posts in bridge, so that will help add height to the bridge.

If the bridge is too low then In reality though I would maybe look at it like an Archtop style bridge setup. using some type of wooden saddle to raise the TOM bridge to spec. This would add visual continuity as well as fix your issue.

If the bridge is too high you can always recess the body some.

Just  my 0.02 cents though.

MK

[Crusader]

Yes the fretboard does look a bit high to me (but not much) Here's some photos of my 59 Reissue LP, hope they help, keep in mind your bridge may have different dimensions

 

Line of top of frets is 14mm at the bridge

 

 

 

Looking at it another way, the underside of the 4th string is 16mm, in other words the height of the saddle. But also note how much space there is between the body and the bottom of the adjusting wheel, its about 5mm

[ADFinlayson]

23 hours ago, peachtree said:

Thanks everyone for the replies! I've stumped up the courage and below is what I have so far - I don't know if it's super clear from the pic but the fretboard laid across the neck plane basically comes in just above the bridge when it's sitting on the body (which is a clumsy way of saying a straight edge across the top of the fretboard extended over the bridge clears the bridge by 6mm, if it's just sitting on the body.

I think this is usable but probs not ideal - especially after frets/action etc my bridge is probs going to be sitting a little too high. I'll decrease the angle a bit I guess. Do you guys agree?

 

I'd like to see some more pics of that build, looks amazing. 

I used the crimson method of doing this with a hand plane many times. it's simply just the height of the bridge minus the height of the fretboard + frets defines the height of the block which is stick to the body at the scale line then plane down the front until you angle starts at roughly the back of the neck pickup position, then smooth it all out. 

height of planing block = (height of bridge + 2mm) - (height of freatboard + height of strings).

For a tunomatic bridge a planing block of about 8mm will do it. 

I still (kind of) use this method now but I do it with the drum sander 

If you watch my vid from 26:28, you will see what I mean