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I have recently noticed something that has never occurred to me. I've seem side sets joined to neck and tail blocks with about a 1/8" gap. This makes so much sense! Gonna cut that away on tail block and neck and heel and binding solves problem at neck. And no more gymnastics to get sides straight!! Is this what everyone else does? (I use M&T bolt on).

Mike

Pretty much. You can use shorter sides too!

Pat

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Pat

I go for seamless with a single piece of purfling at the butt that is installed with the blocks...

Why?

It IS easier to line up the center line on your blocks with the sides if you have a perfect center seam. Without that center seam, I make a centerline on my table that the mold is aligned to, then I align the center line on the block with that. Bottom obviously.

Pat

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Pat

I use a butt joint for the neck so it has to be perfect there but at the tail block I don't care. None the less I have adopted a method of setting the sides to the right shape on my work board, clamping them together and running them through a band saw so they end up being flush anyway.

So many ways to do everything! At the headblock I glue a scrap of "side" material between each of the sides and the headblock, positioning the ends of the sides apart with a 2" wood spacer. This forms a 2" wide by 0.15"-0.2" deep mortice for my tilt-adjustable, bolt-on, elevated-fretboard neck (which is constructed with a 2" wide heel). At the heel block I let things fall where they may, as I often use rather wide tail grafts. (My headblocks and tailblocks are, typically, around 6" wide, allowing braces between the headblock and the tailblock on either side of the soundhole. This frees the soundboard from most structural duties, allowing very light soundboard bracing other than what's needed to control bridge rotation.)

I go for a seamless joint at the tail for the same reason Pat mentioned above and just because it's something to aim for as a kind of a personal challenge and I see it as practice for getting tight joints in other instances where it matters more. Sometimes I end up with a small gap like 1/32", but that's fine. I mark the ends of the sides in the body mold and then cut them on the band saw using a method I picked up from one of John Hall's videos that works really well. At 7:00 https://www.youtube.com/watch?v=MYNibtaUhs4

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

+1

Sounds like a good practice.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I've always tried to get mine to line up perfectly but I've never really nailed it, except maybe getting lucky a couple times.

I remember seeing someone's method somewhere that they cut both sides at the same time on the band saw and somehow used a little shim that was exactly the same thickness as the band saw kerf. Never got around to trying it and don't know where I saw it. Anyone remember that?

Check out this one!
https://www.instagram.com/p/CIiqRRGnL0V ... cxqa9wbi85

Pat

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Pat

I also try for "seamless" joints, but if it doesn't happen I don't fret about it. If I get a nice grain matchup at the tail joint I will sometimes skip the end graft. The neck end is also nice to get tight but again - not critical.

I like to have the sides butt one another, Usually use it to tension the sides right into the mold. Also when I am gluing on the blocks I position the block right on the joint. I do not stress a perfect joint but I usually get one. I cut close on the band saw and touch it up on a bench sander giving a square edge to the top.

On classical guitars or if I have an end graft instead of a wedge I preinstall the end graft on the end block and joint the sides right to the graft. This eliminates cutting out the sides for the end graft.

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http://www.Harvestmoonguitars.com

I do seamless joints. Mark with a square, saw with dozuki, and then drag on sandpaper to refine it. Use a tape hinge to pull the two sides together during glue-up.

But if you're going to do a tail wedge and you're building with an outside mold, then I don't see any reason to bother with accurate side cutting. Cut them short, clamp into the mold with spreaders, and glue the tail block according to the mold centerline.

removed double post

To help me better understand what you are getting at, what do you mean by "And no more gymnastics to get sides straight!" and "achieving balanced sides"?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Here's how I cut sides to length recently. No end graft needed if the sides' grain is well matched (mine wasn't). The fit was tight and centered on both blocks. First, clamp the mold sides together. Then the side is clamped tight in the mold and a backup block is clamped to the inside even with the mold end. An oscillating multitool is used to cut the end off flush. Thanks to Clay for pointing out the many possible uses for this tool.

Sorry for the double post, how I did that?

Gymnastics: getting everything lined up and sides perfectly straight while no gap appears at tail.

Obviously, this can't be done for a cut away at the neck block.

Someone asked: I saw John Hall do the end seam cut on a bandsaw.

I clamp each side in a separated half of the mold, trying hard to make sure each side fits to that half of the mold as tight as possible. I mark it with a pencil, then cut it just a little short on the bandsaw. When I glue the blocks in, this gives me a slight gap at each end, which help to make sure everything will fit where it is supposed to go when it is all glued up. The gaps don't cause a problem, because I use a tail graft on that end and the heel/heel cap cover anything going on at the other end. I have to be careful when defining the center line, because it might not match up with the precise centers of the gaps. But that's not a big deal.

I mark them in the mold, cut them in the bandsaw a bit proud of the line then clean them up on a 10" disc sander with 120 grit paper (I use 120 on the belt/disc sanders and 80 on the drum sander). I also go for a flush fit and usually get it. I don't spend a lot of time on it and it's no big deal if I miss.

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Steve Smith
"Music is what feelings sound like"

I would not have brought this up had I not seen it in person and in one of Robbie O'brien's videos. Sometimes. achieving a perfect seam at both ends AND getting the sides snug to the mold can be difficult. If I am using an end graft (I do), why sweat that? We all use necks with heels.. same thing. I have had some time to think about it. I think the same thing could be done for cut aways.

Regarding cutaways, I think I would recommend the same bit of care that I exercise when I use just a piece of binding as the tail graft instead of a wedge: Don't let the gap be too big. Binding tends to be 1/4" wide at the most. You have room for the gap to be there, and to be imprecise, but not as much room for error as when the tail graft is a big wedge.

I cut a slot in a piece of scrap with my BS blade, then fit a spacer in the slot - loose fit. With the two sides clamped where I want them in the mold, I spread the 2 halves of the mold with the spacer and cut the 2 sides. Works perfectly with virtually no touch-up

You are right Mike,
It isn't necessary to make a perfect seam if you are going to later cut through it, or cover it over completely. If my sides are a little short and I need to gain an inch or so I will leave a gap at the end blocks. Even when doing that a modicum of care is needed to make sure you don't leave too much of a gap on one side or the other.
One advantage to making a tight seam as a matter of course - when you do need to do it you have had some practice.

Very nice! Can't get any more invisible than that with an endgrain joint in maple. Did you use the tape hinge method to pull them together during glue-up, or just a tight fit in the mold?

And off topic, but is there any reason other than habit to do stealth binding on the back? Soundboard binding is important to protect the softwood edge from impacts, but back binding seems functionally unnecessary to me. And unbound backs have the advantage that they can be peeled off fairly easily for repairs if it ever becomes necessary. I mainly leave it unbound to facilitate the heel slip neck reset procedure, since I like integral necks. But I am curious if there are any factors I haven't considered.