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I've seen a couple of pictures where the neck angle is being set before the back is glued on and thought I'd try it for the current guitar.

Upside - Getting the holes drilled for the M&T are way easier to line up and get right.

Installing and removing the neck is way easier as well to set angle, floss etc.

Downside - The neck block can flex quite easily as the back is not there to stabilize it and change your neck angle.

I assume (still waiting to replace the back I ruined) that making sure the neck block is at the proper angle while gluing is important to preserve whatever neck angle you've achieved.

In which order do you install neck, set angle, back install?

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Are you using the outside mold method or the workboard method?

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Old growth, shmold growth!

Outside mold.

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I would worry things could shift or flex making the final setup much harder,especially the centerline

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MK5acoustics.com

I'm actually worried about the flex right now as I've seen the flexing effect the neck angle. Center line seems stable but had not thought of that. I could always set the neck again, re-tune fine tune the angle after the back is on which would have to be done any way.

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It sounds to me like a way to make things much more complicated than they already are. MHO.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

What kind of linings are you using? Reverse kerfed linings stiffen up the sides quite a bit, and would reduce the flex without the back. I usually fit the neck prior to closing the box for the reasons you mention. Haven't had a problem with the neck block shifting when the back is installed, but I use solid laminated linings that make the sides very stiff.
Scroll down & you'll see.
viewtopic.php?f=10133&t=37283&start=50

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

With mike here. I just can't see the benefit. Too many things could change

Thanks Rodger. You're the only one who responded so far who uses this method.

Yeah I'm using solid laminated linings and the box is pretty stiff without the back. I love the ease of installing the M&T neck and if all I have to do is keep neck block angle consistent (and there's a reasonable way to do so) then I'll do it again. I just don't have any experience with this yet and I'm committed at this point.

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This actually makes it much simpler to get the neck right, working right through the open box. It will indeed get complicated if gluing the back on changes the neck angle drastically, but if the angle can be preserved then it should be OK. Where's that crossed fingers emoticon?

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LarryH, my best wishes to you. If you have a way to do this without the risk of the headblock orientation changing, then that's good. But I would not attempt it for those reasons.
Please ignore thre paragraph I deleted. I misread your original post.

Which is why it sounds like a waste of time, or doubling up on work you already need to do. Just making the process a lot longer, IMHO
Please don't take me wrong, because I really do wish you great success. And Rodger has much more experience than I do.
Just giving my opinion, since you were seeking them.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Yes Mike and thanks so much for your opinion. I hope I didn't diminish its importance to my thinking and process. I did not intend that.

What I was trying to say (badly) was that setting the neck is simpler with the back off, and if the back goes on without incident, then the whole process will indeed be simpler. If the back goes on and the head block orientation changes - then it gets complicated - and by leaps and bounds. I'm not a very experienced guitar builder so I'm thrashing on a continual basis so when I see a pic like Rodger's I think, "I'll try that. What could go wrong?" I'll let you know of it goes wrong:)

And again thanks very much for your input.

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Larry, I edited my post because I thought it might come across as either aggressive or rude, which I in no means intended.
As far as being an experienced builder, you probably outrank me on acoustics. I've yet to build a single one. My experience is with set neck electrics, where everything stays put. I can't imagine trying to set a neck angle on an unstable neck block.

But each of us use the methods that we find work best for us. Find your method, use it, and build great guitars.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Although I've been building for 13 years off & on, I've only built half a dozen acoustics, so I don't really have that much experience. I'm still developing my technique, and I've only done the last 2 as I've described. I actually started doing it that way to help align the neck with the centerline of the body, I don't use any neck angle.
I wouldn't recommend following my method, it's well off the beaten path. I've developed it to suit my skills and tools, and it works for me because I understand how it all works together. I draw my own plans because I cut the sides to their exact profile based on my top & back geometry, which is a little different. The top is flat to the waist, and transitions to a 15' radius in the lower bout. This give me enough drop at the bridge so that the neck doesn't need any angle. I set the head and tail depth, and the back radius is centered over the tail, and the radius is whatever it needs to be to hit the correct depth at the head. That usually works out to also be about 15' radius. I use an outside mold, but only until I have the linings glued in.
It comes out of the mold for gluing the top & back so that I can use my spool clamps.

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

I set my neck angle before I glue the back OR the sides.

I build on a worboard a'la Cumpiano.

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Old growth, shmold growth!

At first glance that would seem to be true. But, let's think this through.

What if the neck block is cut incorrectly?

What if the sides of the mold aren't true? After all, plywood warps, and the spreader thingies y'all use can push the molds out of shape.

even if the block is true it has to be positioned correctly.

But let's say all these things are correct, or you were able to "fix it in the mix", so to speak. You are guaranteed trueness, for sure.

HOWEVER,

If I myself start with a square neck block, I'm ALSO guaranteed a straight square side and neck block, since my neck block is glued to the soundboard flat, and as long as the neck block is square, the sides are square when glued down onto the neck block, so you can't REALLY say that's a guaranteed advantage. Also, since I've set my neck angle ahead of time, and kept my neck block and neck heel both square at 90 degrees, there's no measuring and transferring of the neck joint angle from the body to the neck heel, no flattening of the area under the fetboard due to doming the entire top, and reduced fussing of the neck joint fit, all to get everything to sit together straight and true in order to have a straight fretboard from the nut to the end of the fretboard, and no extra bulky equipment to do it all. Now that IS an actual advantage, if only in the time saved to do the extra steps, and the space saved in my small limited size shop!

If one doesn't care about the time, or space, the end result is the same.

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Old growth, shmold growth!

When I consider that 1/10 of a degree change on neck angle will change the string height at the bridge by about 1/32" I think its a fools errand to try and set the neck on an open box. At least if you are looking to build with precision.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

I am not a fan of free building. You want to control the variables in the process as much as possible. If you want a great playing guitar , the mold is one of the best ways to control the symmetry of the body and the neck block position. As Todd points out , a good mold will hold the block square.
There to 2 key points ,
1 is the plane of the fretboard needs to be straight
2 that plane needs to match the top geometry to allow for both planes to match so the final fretboard plane can match the string plane.
jamming the neck block to accommodate a neck angle often distorts the sides and can flex the top in a way that will make this a fruitless endeavor. Make the body , get the body geometry correct and match the neck to the body.
Without proper control you will end up with the dreaded 14 fret hump.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Yeah that's the challenge Brian. As I was working on the guitar I had the neck angle set then I had built a neck rest for future guitars and I set the guitar on the neck rest to test it out. The body was slightly elevated at the neck block and I check the neck angle and it had changed as the weight of the guitar was lowering the fret board clearance by that little bit you are talking about.

Being aware of that problem will probably allow me to get this built and preserve the proper neck angle but the future will bring a different technique.

I can see a scenario where I use both methods because of the ease of drilling the neck block/neck heel holes but may have to abandon it completely. I'll see how this build goes.

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Thank you for the comments John.

I am NOT advocating for this technique as I fell into it through pure ignorance and am simply trying to understand its real flaws and potential for ruining the guitar's existing neck angle.

The fret board and its need to be straight do not seem to be affected and the neck block angle is fairly solid with the solid linings so working on the neck angle at this stage is the same as if the box were closed. Measuring, flossing etc. all remains the same process. Again, please, I am NOT saying this is a good thing or a recommended practice - just sayin'.



In this case there would no 'jamming' of the neck block. In fact, if I understand the term, it would be just the opposite. The challenge is to NOT jam the neck block and preserve the existing neck angle.

I'm waiting for new back material before I continue and am now thinking of ways to preserve that angle. Should be an interesting challenge.

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How do you know I haven't?

I'm simply responding to the things you're saying. You describe your processes as if they're the only way of doing something, and anything else is doomed to failure. That's simply not true, and all I'm doing is pointing that out. If your criticism was constructive, that'd be one thing, but it simply is not. You have to understand a process before you can constructively criticise it.

It actually seems to me that you are in fact the one who can't handle someone disagreeing with what you say without attacking or putting down people.




You can build with precision no matter what, if you are precise.


John, I don't jam the neck block. I don't think you understand the technique either.


However, I agree that he should close the box first and then transfer the neck angle in this case.

I was just pointing out that it's possible to set the neck angle, with precision and repeatability before the box is even constructed. Moving forward, if he likes to use spool clamps, maybe he should consider a different technique.

It would probably work for him.

It seems that there's a small group of people around here who can't stand the thought of not using an outside mold for building, and try to convey the impression that any other method than the one they use is doomed to failure. This is simply not true.

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Old growth, shmold growth!

There are a variety of methods for removing the outer covering of a feline.
The primary reason I fit the neck prior to the back is that I cut the mortise in the headblock prior to glueing it to the sides. I also drill the holes for the barrel bolts in the headblock. I don't drill the tenion until I've got the top on, and it's drilled with the neck clamped in place. That allows me to align the neck with the body.
If you're waiting until after the headblock is glued to the sides to cut the mortise, there's no real advantage to fitting the neck before the back. You're still going to have to make final refinements on the neck angle, I just like to get in the ballpark before I start swinging.
Might I reiterate, I don't recommend following my method, your tools and skills are not the same as mine!

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

If gravity had that effect, what makes you think the instrument will survive 140 pounds of string tension and remain playable? I think there is something wrong.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Brian, What was 'wrong' in that scenario was that there was no back on the guitar at that stage and the neck block was flexing. That was the observed phenomenon that brought me to post here to see how/if I can preserve that angle while gluing on the back.

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Sure! I know a really nice restaurant just up the street. They have great steaks.

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Old growth, shmold growth!