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LarryH
PostPosted: Fri Jan 18, 2013 10:20 am 
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I've read more than once the importance of getting the neck and heel block square (or if I've misunderstood that please inform) but I'm trying to think of what those items would be square to?

They wouldn't be square to the top or back with their respective radii, nor the sides for the same reason, would/could they? So where/what are they built square to?

Or are they more parallel to each other, let's say plumb or vertical to some imagined or real plane?

And what REALLY occurs if they are not 'square,' or plumb, or vertical, or parallel? Is the instrument compromised in some way? How?

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Bill Higgs
PostPosted: Fri Jan 18, 2013 10:50 am 
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Larry,
I think most of this has to do with neck blocks that already have an existing dovetail/slot in them. Otherwise, I would think that any minor discrepency in the actual neck block would be alleviated during the actual cuttiing of the dovetail/slot.
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meddlingfool
PostPosted: Fri Jan 18, 2013 10:51 am 
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When your frame is face down on the bench without top
or back, your blocks should be at right angles to the bench top. If your bend went well, your sides should also be at right angles to the bench all the way around. This will make life easier come binding...
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DennisK
PostPosted: Fri Jan 18, 2013 11:01 am 
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If you're talking about that Cumpiano method thread, then it's just an aesthetic thing, where the headblock is square to the soundboard, even though the upper bout area is angled back relative to the plane of the rest of the rim. Results in the shoulders being angled a bit along with the neck angle, when looking at the guitar from the side.

But what's important in any case with a glued down fingerboard extension, is that the upper bout of the top is coplanar with the neck's fingerboard gluing surface. That is, if you lay a straightedge along the neck and over the body, you don't want a dip at the body joint, or a falloff past it. Although even if there is a little bit either way, you can leave the fingerboard a little thick before you glue it on, and re-level it afterward to take out the dip/hump.
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LarryH
PostPosted: Fri Jan 18, 2013 11:17 am 
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meddlingfool wrote:
When your frame is face down on the bench without top
or back, your blocks should be at right angles to the bench top. If your bend went well, your sides should also be at right angles to the bench all the way around. This will make life easier come binding...


I think this makes the most sense and I can see that having those two items 'square' also creates parallel, vertical planes around the entire guitar that will indeed be easier to get the binding correct. Not something I was concerned with on the current build and haven't really checked for 'square.' I'll bind it soon and check (too late of course) then.

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LanceK
PostPosted: Fri Jan 18, 2013 11:21 am 
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With out trying to over think this process, I draw a centerline on both my neck and end blocks, I then line up the sides with the center line and glue. That works for me.

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LarryH
PostPosted: Fri Jan 18, 2013 11:25 am 
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LanceK wrote:
With out trying to over think this process, I draw a centerline on both my neck and end blocks, I then line up the sides with the center line and glue. That works for me.


Did I just feel a breath of fresh air? :P :P

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Joe Beaver
PostPosted: Fri Jan 18, 2013 9:28 pm 
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I to am a little baffled by what is a 'square heel block'. I started with Cumpiano and a work board. I still do that occasionally (if I don't have a body mold). I've always made my heel blocks the same way, with or without a mold. Maybe I am doing it wrong. As for being square, I put 1.5 degree up angle on the soundboard mating surface and a 5 degree down turn on the back mating surface. I leave extra material on both so I can finalize before the plates are joined. When I'm gluing them in place I use the channel cut in the top for the truss rod to align the block to the tail block

They look like this:


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theguitarwhisperer
PostPosted: Fri Jan 18, 2013 11:02 pm 
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My neck block is square to the neck heel, and orthogonal to the soundboard arch created by the UFB while remaining square to the soundboard. I just have to make sure the block is square where the neck block is glued to the soundboard and also the ribs.

It really just depends on how you are building.

Other methods yield neck blocks square to the ribs, yet the soundboard dome creates a greater than 90 degree angle at that neck block/soundboard junction which needs to be transferred to the neck heel and also the neckblock where the soundboard is glued to it, which is accomplished using a radiused sanding board for the neck block and a neck routing jig assembly for the neck heel,although you can do it by hand with a little more work.

If you have the jigs and power tools it's quick and easy, although it takes time to measure and set everything and is somewhat self correcting for minor imperfections in neck block construction.

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theguitarwhisperer
PostPosted: Sat Jan 19, 2013 12:33 am 
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Todd Stock wrote:
theguitarwhisperer wrote:
Other methods yield neck blocks square to the ribs, yet the soundboard dome creates a greater than 90 degree angle at that neck block/soundboard junction which needs to be transferred to the neck heel and also the neckblock where the soundboard is glued to it, which is accomplished using a radiused sanding board for the neck block and a neck routing jig assembly for the neck heel,although you can do it by hand with a little more work.

If you have the jigs and power tools it's quick and easy, although it takes time to measure and set everything and is somewhat self correcting for minor imperfections in neck block construction.


Some folks cut a 1.5 degree angle in their upper rim from UTB to neck joint, but not me. I radius the top on a 28' dish...use 60' radius on UTB and 28' on X, fingers, tone bars...close box. You are ready to fit neck...no need to sand or touch up anything...the angle from neck block to UTB is already where it needs to be.

For the neck...

- No jig...tenon or dovetail: Cut the neck at 88.5 degrees, taper the heel if you find yourself drawn to that sort of shape, and floss until a straightedge on the neck shows .080 height at saddle location. On a square heel, there's little or no flossing - you'll be right at the required angle. Or do the Cumpiano neck - 95 degree shoulder on a 90 degree miter and a tapered heel will give you the 1.5 degree setback angle.

- Jig: If doing tenon or dovetail and clever enough to have built a Woolson neck jig or have the other production shop neck jigs, hold body in place, adjust until pin touches saddle location, and then rout the neck joint. There is a good reason why so many pros have gone to these jigs....perfect angle and minimal fitting. Mine was built from scrap...the neck joint templates are pretty easy to make.

- No jig...butt joint: Simplest...crosscut neck blank at 88.5 degrees, relieve, stick 220 peel'n'stick to body and touch up as necessary for perfect angle....080" at saddle with straightedge on neck. Neck joint of the future...stupid simple.

Shoot body and neck...put neck on...level the board if not within .001"...bevel the edge of the board at 35 degrees to prevent finish chips as you seat the fret...

Takes 20 minutes from closed box to fitted, flossed neck joint with butt joint, and 30 min with a jig. I usually do three or four bodies as at a time, so an hour to do all of them is not bad. Dovetails take longer and require greater skill to fit and glue...I see lots of otherwise good repair guys that have nasty gaps in reset necks...I'd have them pull and get it right if I were the customer.

Neither approach requires any transfer of angles other than by neck jig, which - like the neck block squaring above - is automatic due to the method. If you can set a mitre gauge or chop saw to 88.5 degrees, you are good. Done this with a back saw as well - anyone that can hand-cut passible casework dovetails should have no issues turning out a neck joint in 15-20 minutes of layout and saw work...none of the work shows (unlike through dovetails), so just cut outside the layout lines and pare to them if your ability to saw to the line is not adequately developed.


So what you are saying is that you cut the neck heel to the correct angle to match the soundbox geometry at the neck joint, and floss it to fit to take up any minor disrepancies.

That IS, in effect, transferring the neck angle, but forgoing the actual physical measurement of the neck angle because you know the angle of the top and simply cut it into the heel when you cut the tenon, plus flossing takes care of the minor saw cut imperfection if any and also wood movement, if any.

And 20 minutes extra work, plus you still have to route or cut the neck mortis in the body, another ten or 15 minutes, no big deal.

Not a criticism nor a personal attack, I rather appreciate the time you take to explain your process as it confirms what I'm thinking.


Todd Stock wrote:

On a square heel, there's little or no flossing - you'll be right at the required angle. Or do the Cumpiano neck - 95 degree shoulder on a 90 degree miter and a tapered heel will give you the 1.5 degree setback angle.


I'm just wondering where you get this from, I'm genuinely curious.

On a Cumpiano neck, the neck is square to the neckblock, so yes there is little to no flossing, but he doesn't taper the heel at all to give the 1.5 degree setback angle. At least, not in my book copy nor in my tutorial notes. I think some people trying his method may be confused by this statement, as tapering the heel 1.5 degrees would yield a 3 degree or more neck setback.

Also, the neck block mortis is cut ahead of time on the table saw when the block is manufactured, an extra 1 minute.

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theguitarwhisperer
PostPosted: Sat Jan 19, 2013 2:07 am 
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Robbie does exactly that with the sliding bevel at about a minute thirty. You haven't seen that?
He actually doesn't measure the guitar, he measures the angle the neck should lie to match the bridge, and you can see a small gap under the straightedge where the fretboard attaches, which will induce falloff if the fretboard is not shimmed.

You're doing the exact same thing but you forgo measuring exactly to the body and simply subtract the 1.5 degree neck angle from 90 and arrive at 88.5 degrees. Presumably your top dome matches, otherwise you would also get falloff.

Incidentally, videos and description like this one are what made me go with Cumpiano's methodology, as I do not want that falloff.

In other news, I see what you are saying, by beveling the saw blade and tapering the heel a'la Martin VS Gibson non-tapered heel, the cheeks would end up angled back after the final shaping is done, as far as the portion actually contacting the body is concerned.

The 5 degree bevel is no longer done which leads me to believe that it was an error in methodology that Cumpiano noticed and corrected (or someone pointed out to him) as the goal in Cumpiano's build is to have the neck heel square to the neck block.

Makes me wonder. I've never actually tried building straight from that book and am rather glad I didn't, even though I enjoyed my tutorial and still espouse the building method in it's CURRENT form for those who would like to use a minimum of tooling.

I will likely stop recommending this book to the beginner, even with his web page and updates. If they want to do this method they should attend his tutorial or wait for his new GMT&T web site with all the updated and correct techniques.

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LarryH
PostPosted: Sat Jan 19, 2013 1:25 pm 
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Great tips and insights from everyone, thanks for taking the time.

The video of RO's does show a 'gap' under the straightedge that I presume the fret board will not follow and indeed have to 'fall off' as it is glued down to the sound board to close that gap. If that's true this particular method needs some work IMO.

I think ideally if your bracing and sound board are truly ready for the neck and fret board that 'gap' has been eliminated by a couple of methods that angle the entire sound board to match the neck angle.

If I understand Todd's method, doming the top at 28' and the UTB at 60' gives a built in angle on the sound board that will accommodate the neck at +-88.5 degrees. I domed the top @ 25' and glued in a flat UTB and the angle of the sound board was just about perfect for the small guitar I'm building.

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theguitarwhisperer
PostPosted: Sat Jan 19, 2013 2:31 pm 
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LarryH wrote:

The video of RO's does show a 'gap' under the straightedge that I presume the fret board will not follow and indeed have to 'fall off' as it is glued down to the sound board to close that gap. If that's true this particular method needs some work IMO.


In the old days some falloff was acceptable as it got those last few frets out of the way and also because the guitar was going to age, and having some falloff leaves a little wiggle room.

This gap can be eliminaed by shimming the fretboard.

I do that when I reset necks.

LarryH wrote:
If I understand Todd's method, doming the top at 28' and the UTB at 60' gives a built in angle on the sound board that will accommodate the neck at +-88.5 degrees. I domed the top @ 25' and glued in a flat UTB and the angle of the sound board was just about perfect for the small guitar I'm building.


Interestingly enough, both methods build in a "neck angle" to the soundboard. With the outside mold, the block is glued square to the sides, and the neck block is move out of square to the soundboard IE not orthogonal, hence the 88.5 degree cut when making the neck tenon.

With the workboard method, the block is glued to the soundboard and held at that angle orthogonal to the soundboard as the sides then back are glued on, so the shoulders tip back square with the neck block, hence the 90 degree cut.

All my necks get wood binding, and I do the final radiusing prior to fretting after the neck has been attached anyway, for extra trueness.

Todd Stock wrote:
On methods...there's so many different ways that folks learn that there will always be a market for classes, vids, books, etc. Some folks just can look at a project and figure out what to do and how to improve the process...for these folks, the best way to help is stay out of their way...Chris V was this way...way smart. There are folks that cannot make a move without a detailed explanation of all the steps and the final outcome...these are the folks that need very structured, organized courses and extensive hand-holding. Somewhere in between are those folks that need a little guidance and enough course corrections to keep them moving in the right direction.


I taught myself how to build electric guitars all the way from scratch with no woodworking experience prior.

I wanted to shorten my learning curve so I took a tutorial, then went home and adapted everything to my small workshop in my garage.

It was fun!

If I lived closer I'd likely hang out at your shop here and there just to annoy you.

The guy who uses molds over here isn't very friendly.

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Trevor Gore
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