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I've messed up again but I'm wondering how big it is at this point. Here's the deal,I had this spruce top that had beautful medullary rays throughout and a nice tap tone. I put the box together and then when I needed to flush the bindings down I found my scraper was too dull to do the job and I wasn't sure how to sharpen it so I used my random orbital sanded to do the job. Big mistake! Now yesterday as I was gluing on the neck I noticed that there is quite a bit of what looks to be runout in the top that I never saw when I started. I'm thinking this came about from using the RO sander on the bindings.

Obviously the best thing to do is take the neck and top off and build a new top. But what would happen if I don't? Will this top hold up? I'm almost thinking it would be worth putting together just to see the results.

I should explain that this is a four string ukulele that's going to be my "take anywhere uke". It's my first solo build (I've built two others in a class) and the first in my new shop so I my main goals are to learn more and start developing my own building style. I never expected a great instrument right out of the shute.

Lastly, from the start this top has always had a nice sound to it. It would be a shame to trash it if it's still usable. So what do you think? Should I replace the top or finish it up and see what happens?

Your thoughts on this would be greatly appreciated.

TIA,

Roy   

Hi Roy,

What's a little runout? No big deal. Martin and other manufacturers, as well as a lot of hand-builders have used wood with runout for years without any real issues. I wouldn't sweat it...go ahead and use it.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I'm confused (no rare thing). I don't understand how run-out can be created by sanding...it's either in the wood or not in the wood. If one sands deep whoopty-dos then end grain can be exposed, but I don't think that's what you mean. Sanding exposed the run-out? Please edecate me

Roy, it was already there. You just uncovered it while sanding. Like Don said, no big deal. Go for it!

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I agree. No big deal. Use it as a learning thing, and let it live and rock on.

Larry, that was my impression as well...it's there or it isn't.

Runout is most easily detected by a light/dark color difference between the plate halves, depending the angle it's viewed at.

Roy, could you possibly mean the exposed medullary rays that can be seen from sanding the wood?

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I would say at least 80 per cent (probably more like 90) of all guitars ever made have some runout (most trees grow with some twist to them). Check out the Daddario poster ad of Dave Matthews and his high end shell bordered 12 series Taylor ( I have it in my shop to illustrate to students). The photo clearly shows a difference in colour form one top half to the other - thats runout baby.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Differences in color is run out. If you look at darn near every piece of quartered and book matched wood you will see this difference in color. Seeing this is important when doing a bridge removal to avoid tear out when separating the bridge from the top with your knife. Go against the run out and you are likely to tear out a good bit of top wood. go with the direction of the run out and you minimize the tear out.

It really is not a color change but a refraction change caused by the run out being in mirrored planes

I certainly would keep it Roy! Go for it!

Thanks for the advice. I'll continue on with it and post a pic or two when finished.

Larry: Sorry about the confusion. My "rookieness" comes through even when I'm trying to explain myself here.

You can check for runout in a top by examining the angle of the grain at both ends of the top. If there is runout, one end might have perfectly vertical grain & the other end will be off quarter.
If you see near perfect vertical grain on both ends, there is little or no runout, as long as the top was cut from split (not sawn) billets.
If the grain is off quarter a bit, & it is off quarter in the other direction at the opposite end there is runout.
Now comes the confusing part. When you flip the top end for end, if the grain *appears* to be reversed (looks like a back slash on one end & a forward slash on the other) and the angle is about the same on both ends,the runout is minimal.
If both ends *look* the same on an off vertical grain board there is runout.
Another way to check is to cut of a small piece in the waste area & bend it 'till it breaks. If you get a jagged break line, the runout is probably minimal. If it snaps cleanly at an angle across the board, you can see exactly how much runout there is.
Runout is normally caused by the tree growing with a twist. Poor milling practices can introduce runout, but this is rare, as most soundboards are cut from hand split billets.
In my meagre experience, if you can see a distinct colour shift at the centre line, the runout is fairly extreme.
I've played some beautiful guitars which had a very noticeable colour shift, & though I like to avoid these tops, they can make very fine guitars.
So... To sum up this long winded note... I would't worry about it a bit!
P.S. The only way you can see runout on the face of a top is through lack of rays or a strong colour shift. Sanding can hide your medular rays. When you finish the top, they might pop right back out at you.
So... Be of good cheer & carry on, as if we were all in our right minds!

Daniel M38820.5550694444

Thanks for that great input Daniel, i always thought that tops were sawn instead of hand splitted, seems to make a lot of sense if you want to detect runout before it gets in your shop! if something has to go wrong with a top, the way the billet splits should tell us a lot more than when they're sawn right?Serge Poirier38820.5643518519

Hey Serge;
The billets are hand split. They can be fairy wide, or quite narrow, depending on the size of the tree.
Once the split billets get to the sawyer, he trues up the face & saws tops from the billet. A billet will usually yield 3 to 6 tops.
It is not practical to hand split each top. There would be far too much waste... & a ton of extra work trueing up every piece. Even in a "pefect" log, there is some twist or bend.
Sawing tops from hand split billets assures the best yield & quality while minimizing the waste.

Exactly what i understood Daniel, thanks for the clarification with better words than mine, great info!

Heheh - Sitting here at work listening to Tony Rice's "Misty Morning", and Serge's bear avatar is keeping perfect time!



-Mark

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Thanks Daniel. I'm going to print your explaination so I can take it to my shop and look through my wood to get a better understanding.

Cheers,

Roy

"If you see near perfect vertical grain on both ends, there is little or no
runout, as long as the top was cut from split (not sawn) billets. "

Not necessarily...
If the runout is caused by lousy milling, as the tops milled from the same
log in this photo illustrate,
you will have quartered wood on both ends, but still have run-out...

And I would venture a guess that more runout is caused these days by
lousy
milling than by twisted logs...

But that's just a guess...

[QUOTE=MichaelP] Differences in color is run out. If you look at darn near every piece of quartered and book matched wood you will see this difference in color. Seeing this is important when doing a bridge removal to avoid tear out when separating the bridge from the top with your knife. Go against the run out and you are likely to tear out a good bit of top wood. go with the direction of the run out and you minimize the tear out.

It really is not a color change but a refraction change caused by the run out being in mirrored planes
[/QUOTE]

Micael - Cool tip! Thanks. Now, how do you tell which way the grain is running out (on an already finished guitar I mean).

_________________
Jim Kirby
kirby@udel.edu

to say that the colour difference is runout is not strictly correct. the apparant diffence in colour is merely a visual effect of runout.

on one half of the top the runout is going one way, and on the other half it is going the other. hence the effect of the light on the end grain is different giving the appearance of different colour which will shift as you change the viewing perspective.

Although this topic has been very informitive it also headed off from what I saw as my "problem". You see what I had after using my ROS on the bindings was something similar to this on my top


In my muddled memory this was discribed in a recent thread as being a sign of runout. So after seeing the responses here I finally did what I should have done before ever posting..... I looked up the thread and reread it. For those of you interested, here it is: Figure in Top . I now see that this is not a sign of runout nor was it ever discribed as runout. It was simply caused by my use of the ROS on the top and can be sanded out if desired.

I humbly apologize for the confusion this caused and thank those who took the time to respond and try to help me through this.Roy O38821.5884606481

Those just look like gorgeous medularies, with no sign of runout that I
can see...

You say it's spruce, but it almost looks like redwood to me....

Nice!

Is it to late to ask question in this thread?

If runout is displayed as different color because of the reverse orientation of bookmatches tops, why not reverse one of the halfs so the runout goes in the same dirrection? Seems to me like in a nice homogeneous top the fact that the halfs were not bookmatched would not be noticeable.

Any thoughts?

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Joe Beaver
Maker of Sawdust

[QUOTE=Joe Beaver] Is it to late to ask question in this thread?

If runout is displayed as different color because of the reverse orientation of bookmatches tops, why not reverse one of the halfs so the runout goes in the same dirrection? Seems to me like in a nice homogeneous top the fact that the halfs were not bookmatched would not be noticeable.

Any thoughts?[/QUOTE]
'Cause then you'd wind up with the wider grain in the center on only one half.

Joe,

You could do that but runout usually results in a weaker top. At least with the runout going in opposite directions you might not loose quite as much strength.

Just for those who don't really understand what run out is (that may be nobody but here goes anyway!) Spruce is chosen as the choice for instrument top wood because it has a VERY long fibre. It is most desirable to have that fibre string run as long along the length of the top as possible. Runout is when the ends of these fibres run out on the face of the top. As cutters, guys like Daniel and I hand split our billets so we can make decisiions on how to cut each piece. THe nice big straight spruce trees are easy, I can hand split them into near perfect rectangles and they are a joy saw, high yeild and the only down grading factor is just the wood itself. As Bruce (spruce) said you can definately introduce runout with poor cutting, but I don't agree that that is the significant cause of runout. As Daniel said most trees have some amount of twist or wave to them. The tree that supplied the Lutz that most of you have bought from me split absolutely straight, even on the 36" long billets I processed for some weissenborn sets, but the tree has a bit of curl so you see the top halves. Lloyd Loar used woods from entirely different trees in some of his mandolins, a tight grained section for one half and loose grained section for another (IIRC). The only reason you don't mix and match, again in my most humble opinion, is asthetics. Switching sets around may give you a different end result but not nessecarily worse than using bookmatched sets. For me I think I will stick to bookmatched sets but I don't see anything wrong with switching wood around, but I wouldn't do that to adjust an asthetic in favour of structure. I might go the other way if I didn't typically have a few hundred sets on hand to paw through .

Roy, you top looks PERFECT! The spruce I have looks exactly the same when sanded down the grits with my ROS. I know you are already carrying on but I just want to lend my note of encouragement! Post a picture once the finish is on!

Shane

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Canada

Roy; That top is truly exceptional. You're a lucky dude to find one that nice. Just wait 'till you get the finish on that puppy! Yeeee Hah!