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The runout question has spawned a number of threads recently and rather than hijack those I am starting another with a more tolerant viewpoint.
This question was revisited recently with jfmckenna's post about a persnickety client. Somehow the notion was embedded in the customer's mind that any visual evidence of runout disqualified the guitar outright. I think it is safe to say the customer's opinion did not stem from knowledge of tree anatomy. No doubt he read an opinion somewhere online and adopted the concept as gospel.
My points are: if runout were such a cardinal sin then why have I played a number of vintage guitars with visible runout that sounded great? I have played some very early Gibson J-45s that were as rough as a cob inside. Coarse saw marks on the braces, mismatched mahogany pieces for sides and back, visible runout on the soundboard. They still sounded great.
Conversely, I have played numerous luthier-built guitars with all master grade materials that left me cold.
Point is materials are just one part of the equation.
If we were building guitars pre-WWII we could afford to be more picky. The world's forests were more vast. Sawyers were not nearly as knowledgeable or efficient as they are today but the sheer quantity of wood could allow for more "skimming the cream".
Well folks, it is a different world today. I think we are lucky to still have any old growth spruce at all given the mismanagement of our forests. And we cannot "eliminate" runout. We are just selecting based on a parameter. Twist of conifers will still happen.
So, yes, there can be "too much" runout that disqualifies a particular soundboard. This qualification is left up to the individual builder to ascertain.
And woe is us as luthiers if more nightmare customers like jfmckenna's start rejecting guitars on visual parameters based on something they have read rather than how a guitar sounds and feels.

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Stay with the happy people.
--Reynolds Large

I have always wondered why bear claw is so desirable. To me, it looks like a lot of localized, variable runout, which supposedly would be prone to fracture.

I have never seen a spruce top that did not show the refraction variance from one half to the other.

If the grain is evenly spaced, why not slip match to avoid the visible variation in refraction from one side to the other.

I do not like the look of giant curl marks on a top, which I suppose is some kind of runout.

We are just finishing a Lutz top flamenco guitar that has no runout at all. I'll try to remember to post a photo of the top before we deliver it to the customer. Perfect tops are still available although not as common as they used to be.

I bought a few Engleman spruce tops from a Canadian Sawyer that have significant runout. But the way they were sawn was designed to have one edge with no runout, and the top diverts from that ideal as you progress to the edge of the lower bout. I haven't built with one yet, but I did join a center seam and plane it smooth before adding a bit of shellac. I was surprised that this board with obvious runout didn't have any color difference jumps along the center seam.

I don't know how this fits into other builders and customers vision of runout is perceived. I thought it was clever that the obvious change in color can be minimized by a clever Sawyer.

As a luthier my main worry with run out is not the loss of stiffness along the grain. I measure the stiffness and take it into account when thicknessing the top. One with run out will end up a bit thicker and heavier than it would have been without it, but usually the difference is not large on an acceptable top.

What I worry about is what's going to happen when (not if) the bridge starts to lift. The side with the run out rising toward the neck will start to lift a little sooner; the glue line seems weaker. The other side, with the run out dropping toward the neck, with see wood peeling, which splits downward into the top. This can be a real problem if you don't catch it right away and take a lot of care removing the bridge.

Many tops I see have some variation in the run out from end to end. In that case I'll do my best to have the section with the least run out fall where the bridge will go. Ideally you can put the worst section under the fingerboard. That's if you can't minimize the issue some other way, such as by using a 'heart' match instead of a 'bark' match; most tops that show run out are worse on the bark side.

I've always rather liked the results I get with bear claw tops. The localized changes in stiffness seem to make the tone more 'interesting' in the high end. You do, of course, need to be careful about where the bridge goes, as said.

I accepted nominal runout a long long time ago. I do have two brands, and I'm much more selective in the top tier budget, but in the 'daily' tier it owes with using aa wood...

I used to be really worried about this sort of thing... Until I saw some fantastic pre-war Martin, Gibson, Lyon and Healey, and some cool old European guitars.... Most of these were over 100 years old.

I noticed that most of these old guitars used a sort of "ground" under the top finish coats which obscured the shimmer of the wood while allowing the grain lines to be seen. Looking inside with a mirror - you could see fairly pronounced runout - the ground simply obscured the underlying wood such that runout doesn't show...

Interestingly - the "natural" tops on some of these were a spruce colored ground under the clear finish... If you didn't know any better - you would swear it is the natural spruce... But the few worn spots gave it away....

And never mind the painted guitars.... As I looked more carefully - I was surprised to find that some of those fine painted guitars don't even have matched tops. They may be made of 2 or 3 pieces of unmatched spruce.

Maybe we need to learn a trick or two from the old masters.

You can probably place a fair amount of the blame on me. I've spoken about runout for years on the AGF forum. Aesthetically, I don't like it at all. But that's all it is - a visual preference. However, I have also spoken out about how difficult it is to eliminate slight runout and I have advised customers to either seek out a luthier like me (who will make certain there is none in the final product) or just buy guitars that are already built. It is absolutely unreasonable for any buyer to expect ultra high-end guitars to never have runout. Runout is a part of the way these trees grow and it does not infer lesser quality if a top has some runout. There are quite a few guitar buyers who don't understand this salient point and we should do our part to educate them on the matter.

I'd advise builders to not "defend" themselves if they don't mind runout. Just say you either don't mind or like the look and recommend these players find someone who has an aesthetic more aligned with their own. Or if you take their commission, learn to identify runout and not let it into the final product.

Minor runout on spruce is a non-issue in any way other than counting fairies on the head of a pin. Just remove a few hundred bridges on old guitars ... every day guys ... every day ...

I've had customers that have complained about slight variation of string angle coming off the back of the nut to the tuners. "The customer is always right" is just another one of the stupid phrases that is meant to shut off someone's brain instead of critical thinking. Just like other phrases, "our policy is ...". Not to digress but likely time is better spent discussing topics that are more relevant to advancing the cause. In fact, nearly any cause. This is not one of them.

As I mentioned in another thread, if you have a top that has grain lines that are "even spaced" top to bottom, you can do a "flip match" and hide the runout. The top can have uneven width grain lines edge to edge and they will appear to be in their proper position with a flip match, where a slip match would make them more obvious.
I was looking at some tops I glued together several months ago, and after examining one very closely I noticed I accidently did a flip match on one of them. Oh well!, It is really hard to spot, so I will leave it that way.

I for one am happy to read the comments of this thread. As stated in several posts, Most trees have some twist. How a sawyer dissects the material into soundboards, and where he/she puts the little bit of slope in the board, by the way it's sawn, will determine both how it looks and where the most strength is preserved.. But to build a GREAT sounding guitar, that is where your craftsmanship, knowledge , understanding and application of the art of lutherie comes to play. Keep up the great work of building and we will keep up the great work of producing soundboard products..
CF martin is a stickler about grain slope, At least that is what Albert- the new wood buyer, told me. I had been knocking on that door for the past 15 yrs. After a well received meeting at Winter NAMM, I explained grain slope to him, we received an order for 100 #1's. I didn't send any of our top shelf product, because that's not what they ordered. They received the shipment. And last Friday Albert called with the report. It was SOO Cool. The comments from the purchaser[Albert] and the production manager.,. It was pretty much like they gave us hugs on the phone. So of the 100, 33% made their top shelf and another 24% was just 1 point lower. So 57% for the top 2 in house sorts. Then the fact was mentioned, of their appreciation about the salvage aspect of our acquisitions. That put big smiles our our faces, again. This is GREAT News for you folks. With increased product sales, we can increase production, open up and see more material. This new factory was built for this, and has been at pretty much an idle, compared to our capabilities.

Brent,
I haven't had the pleasure of working with you guys yet (my inventory is well stocked at the moment) -- but it sounds like you're doing a great job. I'm sure I'll be in contact with you in the future.

Well done! Next batch of Sitka will come from ASW.

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Tony Thatcher
Bozeman, Montana

]I am somewhat confused about the term runout. It seems that some talk about the physical arrangement of grain lines, and others about the grain flow of the wood. I think better in pictures.

The top shows what I think some people talk about. Perfectly straight grain lines from the end view. On a guitar, this is even hidden by the binding so who knows? But I have watched videos where well known makers even say that a 5 piece top would be better its it could be perfect, and perfectly split. Now I guess there he is talking about perfectly split.

The middle is what I think of as runout. The way that the grain runs. This isn't seen except by the maker either, but in many cases can even be 'felt' by him, as he is trying to plane against the grain. Isn't that what gives the color differences?

But sometimes the color changes aren't there. I had a maple violin back that had it really bad. But I kinda liked it. Now that it is varnished, it isn't as noticeable. Maybe with a more clear finish it would be.

I had a Sitka top that was very curly. Had to watch how I planed and scraped it. I think of it as having a spring built into the long arch. Maybe; maybe just wishful thinking. All that grain changing, and you would never know it from the outside. Was trying for red over gold, and it looks brown except in bright light. Looked better at 1.8 m pixels! Photos are so hard to do.

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Why be normal?

When you cut a flat board from a spiral growth tree, the runout will vary along the width of the board. It could have zero runout on one edge, and 2 or 3 inches on the other edge. The goal as a sawyer is to cut it so that there is zero runout on the joining edge. That way, there will be no difference in reflection at the joint, even though there could be runout on the outside edge of the top.
When selecting red spruce trees or logs, I always tried to keep the spiral to less than 2 inches in a 2 foot long block.

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John

Ken,
The middle sketch is what most people are talking about. To determine runout I usually split off a piece of wood from the edge I'm checking and then split it through the middle of the thickness. As the split runs along the length it will tend to "runout" of the piece. If you split an 1/8th inch thick top in the middle it will start at two pieces of 1/16th inch, one of which will probably run out eventually. Measuring the distance in 1/16ths will give you a ratio. If it runs out in an inch and a half it would be 1:24, 2 inches = 1:32, etc. How much runout you tolerate is a personal matter.
You will find tops where the runout is different from edge to edge, so measuring both sides and joining the edges with the least runout will minimize the color shift at the joint.
Like many of the grading criteria for tops, runout is mostly a cosmetic problem, unless it is extreme. Most of us evaluate an instrument with our eyes before we play the first chord.

Ken, As Clay stated the middle diagram best illustrates runout, and second is your illustration of the curl, of how the islolated and specific slope of the fiber, that is the result of the curl. In a log the curl will be lumps on the outside.. like your knuckles. However, one should realize the distinction between the growth line/rings and the fiber itself. You know there is taper in a log, and most lumber and boards cut on a sawmill will have the slope of growth lines in the length of the board. The more taper there is in a log, the more you will see this type of “slope”. But grain slope when referring to runout is referring to the fiber, and is from twist of the fiber in the tree/log. I cut some rounds off a log this afternoon and dissected them into blocks for re-sawing into archtop fronts... I will bring some photos and describe whats going on for you guys tomorrow.

Yesterday I cut 3rounds off a 30’ x 27” sitka bridge stringer log. I ripped the rounds into resawable quadrants after reading the round. In these instances, “we’” rip the block with chainsaw to reduce waste and maximize recovery. After 24+ yrs, we know what we’re doing. Instead of loosing roughly more than 1 full archtop front due to the pulled grain and fiber of an uneven split, we minimize that waste to the 3/8” kerf of a sharp chisel ground chainsaw chain rip.
I also took a couple pics of larger log. 46” diameter, but I am not able to reduce the size on this ipad to post. One log is absolutely straight, while the second had the same 1” twist per foot. But because of the size, the field of 12” VG face width, the twist in the resawable block is reduced to under. .3” per foot. But the same technique would be used when resawing, by determining which edge would best be used for the join edge, by reading the texture and color of the field, then crowd the slope for “no apparent runout” tops.
Here is the video of show and tell of the smaller log for archtops. I cut20 today. And went to the dentist too LOL! https://youtu.be/RKWSvCQ747Q

That's an excellent video thanks for that. So Is that just the way it grows? If I am understanding correctly, on the bark edge the slope only goes in about an inch or so then it straightens out till it gets towards the pith and then slop occurs again but in the opposite direction?

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Also I always here knowledgeable luthiers talk about joining tops on the bark edge or the opposite edge but I've never bought a top that has bark on it

How does one know where the heart edge or the bark edge is?

Yes John, There are just a few out of the millions with no twist. But Most trees have some twist, and as described in the video, that is how they grow. There are a few though that have what we call a rind twist. I don’t know how it happens, except some trees after a “big Event” that changed the tree’s growth pattern drastically, and usually accompanied by a pitchy growth line, That the tree grows with extreme twist. In those trees, we can split the outside 2-4” of meat from the round, and then the rest of the heartwood can be split, or ripped without any significant grain slope/twist.

There is no way of a receiver of tops to knowing which edge of a bookset is the heart side or sapwood side at least from old growth timber source. Knots can show up after 200 yrs of growth. And changes in the forest, due to blow-down event can have acclerated growth and wide grain after 300+ yrs of very slow growth. Only the producer knows after getting personal with the tree, LOL. I mean finding it, dissecting it and seeing the recorded history in the makeup of the fiber, and then dissecting the tree into product.

Brent Cole wrote:
"There is no way of a receiver of tops to knowing which edge of a bookset is the heart side or sapwood side at least from old growth timber source."

Generally that's true, particularly on the really old growth stock he's getting. Sometimes it's possible though. The key is that, in general, the earliest growth in the spring is the fastest, because there's lots of warmth, moisture, and sunlight. Later in the season as things get drier the growth slows, and eventually stops as the winter cold sets in. The early growth has relatively large cells with thin walls, and as the season progresses the cells get smaller and the walls thicker, until the growth stops for the year. The thinner cell walls make lighter colored 'early wood', while the later growth is darker. Thus the year's growth in a ring tends to start out lighter and softer, and shade into darker, redder late wood, which comes to a sudden end at the start of the next year's light and soft early wood.

The width of the growth rings and the pattern of their shading provides clues as to the life history of the tree. Sometimes you'll see a wide growth ring that shades off gradually into a very narrow late wood line: the sign of a good year. If the lightest early wood is very narrow in the ring, with a wider darkening line, it can be a sign that rain has been scarce. Correlating these sorts of things over trees grown in an area over time is part of the science of dendrochronology. By finding trees with overlapping dates they can step things back thousands of years and provide very reliable dates. But I digress.

The point is that it is often possible to tell which is the bark side of a piece of wood by the way the ring lines are shaded. Groves of big trees in a sense make their own weather, and that reduces the amount of such shading that you see. And, of course, narrow grain lines don't give much scope for shading. Still, it can be possible to read this in many cases.

When I join and glue up soundboards I do several at a time. I was looking through the tops I have glued up and ran across one that on close inspection I noticed I accidentally "flip matched". Since the grain lines are relatively the same top to bottom it was hard to spot. This top will have the run out running in the same direction on both halves, which should make it hard to discern. If you orient the runout rising toward the neck it may avoid the issue Alan mentioned of a lifting bridge peeling wood, so in addition to the cosmetic difference it could make a structural improvement.

Can you see that it is not book matched when you stand back from it though? It looks fine otherwise.

I know you are not saying this but I often hear others say you can 'eliminate' runout by joining the tops in succession like that. Obviously that's not the case but seems to be one of those things often said. It might hide the appearance of runout but it's still there. So I guess that is a trade off. You forfeit the appearance of book matching for the appearance of a runout free top.

Because the grain is fairly straight and there are no obvious "markers" the top does appear to be book matched to the casual observer. Even with book matched tops the "outside" of the book can be less well matched than the "inside" of the book. This is more noticeable in hardwoods, but close examination will show it in even vertical grained softwoods (to a much lesser extent).
I did take a picture of the entire top, and I will try to post it:

Yeah that is indeed very hard to tell.