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Hello All,

I have a nagging question, prompted by a couple hundred pounds of red spruce in my basement. I'm going to try to describe something that is best seen so please bear with me.

I got a 6 foot length of red spruce last May. You should have seen me splitting it, more than one neighbor was worried for my health - and sanity - and offered to swing the sledgehammer for me. I had to use 4 wedges to split the log pieces in half (it was cut down to 25 inch lengths at the lumber yard). Took me a while but now I have these roughly wedge-shaped hunks drying in my workshop.

Resawing the spruce is next on my to do list. There is a bit of twist in this log but it is still acceptable. (I believe the twist falls within limits set by Martin and those who build wooden airplanes out of spruce - I found them on the web several months ago, can't recall the details or urls.)

Anyway, I can get well quartered slices but because of the twist the lengthwise axis of the grain in the center of the tree differs from that of the outside (bark side). In resawing it I will follow the lengthwise axis of the grain on the exterior (bark side) surface - this will keep the runout to a minimum in what will become the center of the soundboard. The part of the soundboard that will be towards the outside edges (what was in the middle of the tree) will have more runout.

My questions:
1. Do any of you builders and wood-meisters know what effects this may have on
a) the soundboards' tone?
b) the stability of the soundboard?
c) the appearance? I just LOVE silking. Big time.

2. Any pointers on working with this wood?

Thanks for your interest and help.

Best wishes,
Viv

Hi Vivian.

You've discovered that in billets with any twist at all, you can either saw for ideal quarter or for no runout, but not both. If you saw for quarter, you'll get better silking, though that's not a real strength in red spruce relative to some of the other spruces (though I've seen some nice pieces). If it were me and the twist was appreciable, I'd saw for no runout (i.e., saw along the split line) and live with imperfect quarter, but that's me. To some degree, my choice would depend in part on how much runout there is...

And you should buy some Sitka billets simply because they often have zero runout and sawing stuff with no runout is a joy!

Good luck.

Wow....that's a real mouthfull....

I suggest letting me come over and remove some of those hunks of wood from you, so you don't have to agonize over this too much.

The real problem with runout, as I understand it, is that it can cause issues when severe. Issues such as a bridge tearing off with hunks of the wood attached. Or when bending sides, it can cause the wood to split and fracture.

But you're talking minimal amounts of runout here, so I don't think it's an issue for you. You may see one half of a top looking darker than the other at different angles, but that's about it.

Hopefully Bob Steidl will see this post of yours and chime in...he has lots of resaw experience with the spruces.

Oops! Nevermind!Don W38393.7063078704

_________________
"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."

Bob,

Thanks for your reply. The problem with the twist is that the split line twists, too. So the split line in the outer 1/3 of the log is different than the middle 1/3 is different than the inner 1/3. It rotates along the long axis.

Maybe I'm just splitting hairs...Like Don W. said, It's not toooo severe so perhaps all be well, or well enough.

So, where can I get me some of that beautiful Sitka with no runout or twist?   

Thanks again,
Viv

Hi Don,

Thank you for your kind offer. That's awfully nice of you.   

Seriously, I appreciate your words of wisdom. You have given me courage to put a new blade on the bandsaw and start making dust.

Hope to see you Sunday at NEL!
Viv

Vivian, sounds like you're sitting on a pretty good stock-pile of spruce.
Bob knows what he's talking about. He pretty much taught me everything I know about resawing. So this words might be repetive of his.
But here's my insight anyway. If I were you, I'd go for no runout vs. perfectly quartered. This can be a bit of a bugger as you physically have to twist the billett as it's going through the blade. It's much easier to lop off a slab and then have a perfect flat surface to put against your fence. In some of the billetts I've cut up, I've done it both ways. The appearance of a less-than-perfect runout guitar looks bad in my opinion. A dark side and a light side, oh, wait, I mean a light side and a dark side...hey somebody stop moving the light source!
So the ones I sawed with a twist looked MUCH better. Once they're stickered for a couple of months the twist is gone and you've got a great looking top set.
Hope that helps. Good luck. Paul

That "two tone" bookmatch just doesn't look good to me even though it may make a fine soundboard. I think this is fairly typical of Adi that I have seen. I have a set like that right now in my shop and can't quite decide what to do with it.

For a recent classical guitar commission, I had to decide whether to go with a German spruce set with some run-out or a perfectly matched Engelmann set. Both sets were equally stiff and sawn on-quarter. According to my builder, either set would make a good top, but I remember him telling me that he preferred to see the run-out rather than saw it off-quarter. Perhaps this isn't the case for steel string guitars?    

Paul, give it a sunburst!

_________________
Tickle your guitar daily, and it'll tickle you back.

Vivian:
I'd cut it as you suggested you might, with the runnout minimised along the join line and the twist causing increasing runnout toward the wings.

There are four things I can think of as issues here.
1) Most important: if there's much runnout where the bridge glues you're (or the first repair person is) in for problems down the road. The bridge _will_ lift in time; they all do within the limits of experimental error, and pulling a bridge from a top with significant runnout is not fun.
2) Cosmetics; it makes the runnout less visible.
3) Runnout decreases the stiffness along the grain. Having the least runnout in the middle of the top gives you the most stiffness where the stress is higher.
4) Trees the grow with some twist tend to untwist after they're cut. Lots of runnout = lots of built-in stress. This can cause warps and cracks down the road: it's a long-term issue. It does seem to me that cutting to minimise runnout in the center might minimise the the stress over the long term. Not a biggie, maybe, but what the heck.

Dear Al,

It seems that we understand each other. Thank you for your reply. As
always, edifying! Now how about edible?

Bestest wishes,
Viv