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Runout question...
http://mowrystrings.luthiersforum.com/forum/viewtopic.php?f=10101&t=50315		 Page 1 of 3
Author:  meddlingfool [ Fri Feb 16, 2018 11:00 pm ]
Post subject:  Runout question...
So I got this engelmann aaa top today.

Looking at the corners, there appears to be extreme runout at the outer edges.

ImageImage
Image

It does of course fall outside the pattern, and I've had other sawyers attribute it to windshake or fall damage or someought in other tops I've used without a problem.

Looking at the join, there does not appear to be any obvious positive/negative at the seam, and certainly there's no sign of runout looking at the centre edge, but unless there's a crack in it like the other edges, I know of no way to determine runout beyond cutting into a chunk and splitting it to see what the grain does. Which would of course make it 'worked' and unreturnable...

Any thoughts?
Author:  jfmckenna [ Fri Feb 16, 2018 11:53 pm ]
Post subject:  Re: Runout question...
The other thing you can do is sand it real good, or plane it even better, and have a look at it under light. Of course that may render it unreturnable too but at the rate that thing looks like I'd just return it. It's hard enough to see runout in the side cut like that so when you do actually see it you know it's gonna be bad.
Author:  Clay S. [ Sat Feb 17, 2018 9:52 am ]
Post subject:  Re: Runout question...
Engelmann spruce trees often grow with a twist (spiral grain). You can have much more runout on one edge compared to the other. I try to match up the edges with the least run out. That top has more runout than I would accept on any edge. It would go on a strumstick or some small cheaper instrument with a floating bridge where the runout wouldn't matter.
Some people check runout by sliding their fingernail along the edge of the board and seeing which way it wants to run. I have had mixed success with this, so I generally split off a piece of wood.
My experience has been that the "higher grades" have the same variation in quality as the "lower grades" and as long as wood is graded on cosmetics I believe this will be the case.
Author:  meddlingfool [ Sat Feb 17, 2018 1:41 pm ]
Post subject:  Re: Runout question...
The thing is, I have a hard time believing that this amount of runout would make it past any woodcutter...
Author:  jfmckenna [ Sat Feb 17, 2018 2:15 pm ]
Post subject:  Re: Runout question...
You definitely need to cut it in the right direction for sure. In fact planing the wood is a good way to see if there is runout. If you chatter in one direction and not in the other then you got run out. But alas that is not even 100% fool proof. The last top I worked with planed like butter all over it but the first wash coat of shellac revealed some obvious runout.
Author:  jshelton [ Sat Feb 17, 2018 2:20 pm ]
Post subject:  Re: Runout question...
meddlingfool wrote:
The thing is, I have a hard time believing that this amount of runout would make it past any woodcutter...

When I was a lot younger my partner and I used to make an annual pilgrimage to Northeast Idaho to get Engelmann spruce. In short order we learned to tell how much twist a tree had by looking at the bark. Straight Engelmann trees are pretty scarce. We would spend days driving the logging roads and hiking looking for the right tree since it had to be straight and harvest-able (damaged, leaning, etc.). Cutting a healthy tree was strictly forbidden by the forest rangers for us ordinary people but the logging companies considered Engelmann a junk tree and would cut it, stack it and leave it to rot.
Author:  Michaeldc [ Sat Feb 17, 2018 7:22 pm ]
Post subject:  Re: Runout question...
I find a cotton glove handy. If I can see a difference in chatoyance in the plates the glove confirms the presence of excessive runout and not so much when I don't see a difference. There will always be a little difference in resistance when run one way or the other, but when you have excessive runout the cotton glove will be stopped in its tracks when rubbed against the grain
Author:  JSDenvir [ Sat Feb 17, 2018 8:26 pm ]
Post subject:  Re: Runout question...
Image

Far be it from me to pee on Kevin Ryan, but would you let this out of your shop?

Steve
Author:  Clay S. [ Sat Feb 17, 2018 8:39 pm ]
Post subject:  Re: Runout question...
"The thing is, I have a hard time believing that this amount of runout would make it past any woodcutter."

Not all tops are cut from split billets, some are sawn to maximize yield. Splitting wood is a somewhat wasteful proposition both from material loss and additional labor. And if you have twisty logs splitting may give you a net yield of zero.

Some runout can be tolerated, and some fine sounding instruments have been built from tops with noticeable runout. Above 1 in 24 (running out 1/8th inch in 3 inches) I would consider it mostly a cosmetic issue (if the top is stiff enough) - you can still see it but the top should be strong enough to hold up and not lose its bridge readily. Measuring from the photos you posted (not the most accurate way to do things, I admit) that top looks to vary between 1 in 12 to 1 in 9. For a soundboard that is 1/10th inch thick the grain would runout (top to bottom) in about 1 inch.

"Far be it from me to pee on Kevin Ryan, but would you let this out of your shop?"

If it was a nice stiff top and the runout was less than 1 in 24, I would. Wood that is slightly off quarter can also create that effect - so wood slightly out in both directions might still work fine but look less than perfect. Looking less than perfect doesn't bother me - I'll settle for "nice enough" bliss
Author:  JSDenvir [ Sat Feb 17, 2018 8:47 pm ]
Post subject:  Re: Runout question...
Really? That can come from wood that’s “slightly” off quarter?

Not being argumentative. Genuinely curious.

Steve
Author:  JSDenvir [ Sat Feb 17, 2018 8:53 pm ]
Post subject:  Re: Runout question...
But even apart from runout/being slightly off quarter, his base price is $10K. So this guitar is probably 13-15K, between the pearl and the bevels.

Perhaps I’m missing something here?

Steve
Author:  Michaeldc [ Sat Feb 17, 2018 8:55 pm ]
Post subject:  Re: Runout question...
JSDenvir wrote:
Really? That can come from wood that’s “slightly” off quarter?

Not being argumentative. Genuinely curious.

Steve


Yup, true...
Author:  Clay S. [ Sat Feb 17, 2018 8:56 pm ]
Post subject:  Re: Runout question...
http://www.lutherie.net/frankford.runout.html

Toward the end of the article Frank mentions that "off quarter" can also create that effect.

P.S. My prices are considerably less than Kevin's, so what I let out of my shop may be different than what he should let out of his.
Author:  Michaeldc [ Sat Feb 17, 2018 9:00 pm ]
Post subject:  Re: Runout question...
Clay S. wrote:
http://www.lutherie.net/frankford.runout.html

Toward the end of the article Frank mentions that "off quarter" can also create that effect.


Also my info source..
Author:  Michaeldc [ Sat Feb 17, 2018 9:06 pm ]
Post subject:  Re: Runout question...
JSDenvir wrote:
But even apart from runout/being slightly off quarter, his base price is $10K. So this guitar is probably 13-15K, between the pearl and the bevels.

Perhaps I’m missing something here?

Steve


If I was buying an off the shelf guitar from T*yor, M*rtin or whoever I'd look for defect in the top hoping it would yield a more responsive instrument due to a weaker top. This has been proven time and again in mass-produced instruments where tops are uniformly thicknessed....
Author:  JSDenvir [ Sat Feb 17, 2018 9:14 pm ]
Post subject:  Re: Runout question...
Interesting. I looked at the FF article and his example was, what, 15 degrees off quarter? I don’t know that I’d accept that from a supplier. Nor would I feel comfortable offering it to a customer.

Maybe I’m just being precious about it. Who knows?

Steve
Author:  meddlingfool [ Sat Feb 17, 2018 9:31 pm ]
Post subject:  Re: Runout question...
I wish there was a way to tell if that amount of runout carried through the whole top, or what the runout was like at the join without cutting into it.

Cause that was a 60$USD top plus shipping and customs. From a good supplier.

i was hoping someone could categorically identify it as windshake...
Author:  JSDenvir [ Sat Feb 17, 2018 9:40 pm ]
Post subject:  Re: Runout question...
Why don’t you send the pictures off to the supplier? If he vouches for it, great. If not, and you discover that the runout is terrible, you can go back to them.

Steve
Author:  meddlingfool [ Sat Feb 17, 2018 10:27 pm ]
Post subject:  Re: Runout question...
Most def...

But not until Monday.
Author:  Bobc [ Sat Feb 17, 2018 11:35 pm ]
Post subject:  Re: Runout question...
I wouldn't ship a top that looked like that. Would probably cut it down to a uke top.
Author:  Clay S. [ Sun Feb 18, 2018 8:23 am ]
Post subject:  Re: Runout question...
"i was hoping someone could categorically identify it as windshake..."

Wind shake is often caused by bacteria that weaken the bonds between the rings, and wind opening them up. I think I'd rather deal with runout.

"Cause that was a 60$USD top plus shipping and customs. From a good supplier."

Most tops are slightly over length and over width. Splitting off a 16th of an inch to check for runout shouldn't kill anything. If you like what you see, keep the top. If you don't, ask the seller to make it good. If he don't, there are several other suppliers who would have, and I would deal with them.
Ten+ years ago I was buying tops a couple hundred at a time with the understanding that they were of uneven quality. Some are quite nice both cosmetically and structurally, and some are kindling quality. Most of them are structurally good, but may have wide or uneven grain ,or color,or "stripey grain", or a pin knot to be worked around. At $5 a top (including shipping) I didn't kick about the losers - they were far outnumbered by the usable ones.
Since you are in the area where the tops are cut, you might consider visiting the mill and check out their "lower grade" stuff. You might find a few gems for not much money.
Author:  jfmckenna [ Sun Feb 18, 2018 6:56 pm ]
Post subject:  Re: Runout question...
I've been having some serious runout issues with a certain supplier that I will never do business with again quite frankly. (not a sponsor here). It's already caused me to retop the guitar once and the top they sent back for a replacement is even worse. It got me thinking too becasue runout for the last 25 years is nothing I ever even considered really. I hand plane my tops so having a good runout free top is a pure joy to plane in any direction but really it all comes down to cosmetics. Some people simply don't like it and I understand and can appreciate that. I just wonder why for the past 25 years I've never really had issues with runout on tops and now within one month it seems to be everywhere.

My guess is that if you split logs into quarters and then saw tops off that then you virtually eliminate runout except perhaps for in the rare case where a tree has some serious twist that shows up in even 30 inch drums. But wouldn't a good sawyer be able to see that? The Carpathian tops that I am dealing with now are very difficult to tell if there is runout. I've done the flash test, split test and rub the hand test and it's only after a coat of shellac and 15 hours of hard work I realize it's crap and needs to be done again. What else can I do to get better at identifying it?

Check this top out. It's actually kind of cool though unacceptable to my client. But it has a mahogany striped chatoyance to it and also the runout doesn't show up as left half/right half but rather checkered almost like the logo for BMW cars if you know what I mean. I've never seen anything like it.

Image

Also look at the diffraction you see with the bracing and bridge patch in this image. It's like poking a stick in water and watching it diffract:

Image
Author:  meddlingfool [ Sun Feb 18, 2018 8:32 pm ]
Post subject:  Re: Runout question...
I wonder if a dose of naphtha would reveal. Think I'll go check...
Author:  jfmckenna [ Sun Feb 18, 2018 9:01 pm ]
Post subject:  Re: Runout question...
meddlingfool wrote:
I wonder if a dose of naphtha would reveal. Think I'll go check...

I think even in that case you need to at least get close to finish sanding. So something like sanded out to 220 grit.
Author:  JSDenvir [ Sun Feb 18, 2018 9:03 pm ]
Post subject:  Re: Runout question...
JF, I’ve got a top just like that on a guitar at the moment, and quite like it. It looks like run out, and in, and out.

It’s definitely weird, but like yours, my top has killer silking, so it’s perfectly quartered.

Thankfully, the guitar my top was on was a test, cause it might be a hard sell to a customer, but I still kinda like it.

But I have no idea what causes it.

Steve
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