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I’m sure that pretty much everyone here cuts their braces from split billets. But just out of curiousity, who splits out individual braces?

Steve

I am so glad you posted this question. I haven't been very actively building for a few years, but I'm tooling up to re-start. I have some red spruce split billets that I got from Ted Davis before he passed away. I also have some from the Hampton brothers that may have been from some of Mr. Davis' old stock. I would also like to know how to properly process these with the respect they deserve. I'm guessing the original concern is for obtaining brace stock with as little run out as possible....?

I'll hush now....all ears.

curtis

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"I need to hurry up, the years are going by far too fast"

I used to, but it resulted in a lot of waste and probably worse grain alignment. A split will only follow the grain if the wood on either side is roughly the same stiffness. Otherwise one side bends outward and the split tends to wander across the grain in that direction. The longer a piece is relative to its width, the more precisely centered the initial split has to be. So it's better to stop with a medium sized piece and saw the rest of the way.

Also, when you're splitting a piece with unknown runout, sometimes the runout is enough that following the grain carries it far enough off center that then the flexing/cross grain wandering starts to happen. Almost always happens on the 1x2" bracewood billets sold by luthier places (which IME usually have terrible runout, not at all worth the price). I always buy bigger pieces nowadays.

Nope. Just plain old sawed stock leftover from top sawyers. Runout is almost always there to some extent. The only place I know of personally to get split stock is in Alaska, so shipping costs more than the product which makes it a non starter...

I am set to experiment a bit with splitting. Thus far, I have only sawn from split stock. No apparent problems up until now, but I thought I would see if it feels worthwhile after some actual experience with it.

I've found that trying to split out smaller sections results in too much waste as the splits "wander" off the grain lines.
If splitting larger billets, I split them in equal halves, then split those at right angles to the first split.
Then straighten two adjacent edges, and bandsaw from there.
Best smaller split bracing billets (3/4" x 3-4") I've had so far came from Shane, very little runout, can be sawn straight from the delivery box.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

This sounds like the same thing I've been doing.

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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

I saw out my classical fan braces to width from thick bracing stock, making sure that the grain is completely vertical. Then I split out individual fan braces from that stock to get just over the desired brace height. These braces are so thin, that any runout will significantly weaken them.

For back and major transverse braces, I just use off the saw without splitting out the stock.

I start with a split and then saw parallel to the split face until that chunk is used up. If you buy quantity from Alaska Specialty, it’s actually quite economical compared to other sources. I buy their box of split face pieces. It lasts a long time and makes it quite easy to select appropriate pieces per brace.

I used to watch for close grained spruce pieces at the big box stores and then split braces out of them, but it’s easier to just buy from AS where almost all of the wood in the box can go into a guitar. My only waste is the short cutoffs and the pieces that are too narrow or small after the braces I need are cut out of the bigger board.

I often source my braces from old lumber - window sash, door material, shelving or 2X stock. I split it and don't worry too much about waste. I wind up with some short pieces, but many guitar braces are short. Some of it is only good for kindling, but since it is "scrounged" material the cost is negligible. Most of what I use is spruce, but if I find another species of softwood I think is good for bracing I will use it.

How much are you,paying for shipping, Bob?

I had 12 tops and bracewood shipped from them for $25 ish about a year ago.

From Alaska?

A few months ago I purchased 4 pieces of Sitka Spruce from them at 4/4 X 6" X 36" and the shipping was $60.

Ed

How much "off vertical", with the grain lines, do you consider a problem on braces? What are the negative effects of being off vertical? Loss of stiffness? Possible twisting later? Other?

How much variance from the split line, or run out, do you consider a problem? What are the negatives here, other than the obvious of braces splitting later. You certainly don't need more negatives than a brace splitting, but I am just curious.

Last time I ordered a box of brace wood, he sized it to a flat rate postal box and shipping was $35, or maybe twice that, if I remember correctly, for a lot of wood. I’m still working on the second box I got many years later, so my memory might not be accurate. But, if you call them (at an appropriate time—remember they’re probably in a later to rise time zone), they will help you figure out the optimum way to order. I ordered the hand split. Most of it was usable.

Being off-vertical has very little effect on longitudinal stiffness. It affects cross-grain stiffness greatly, but that is of no concern with braces.



Runout should be negligible in braces, but a grain slope of 1 in 20 should not affect strength appreciably.

I see no reason to split individual braces. If the stock is straight-grained (as all brace stock should be), then all you need to do is joint one split surface, then saw parallel to that.

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John

I cut a test brace to help me understand the negative effects of run out in braces. The original size was 5/16" by 3/4".
I split the brace in the center of the vertical height and the run out is severe. The end grain is close to vertical as shown below and the grain line for the length of the brace is fairly straight. So the big problem with this example is the amount of run out. What problems can result from this much run out in a brace. Just to be clear, I don't intend to use this brace. I always strive for the least amount of run out in the braces, but I am curious of the negatives of severe run out.

Negatives, well, I believe there is strength (more liable to break), stiffness (reduced), and the speed of sound propagation (sonic qualities) are all influenced by runout.
At the extreme, imagine a brace with vertical runout, bit like a back-strip with grain across it but on it's edge.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Right, Colin. I stated in my first post above that splitting was an obvious problem with run out. The others, like reduced stiffness and sonic qualities are more difficult to quantify. Thanks for the input.

In my example, I think I interpret your 1 in 20, to be 1 inch of movement in 20 inches of brace length. So the run out in this brace would be .375" in 4.875" of brace length, which computes to 1.5" in 20". Am I understanding correctly? If the run out of .375" happened over a brace length of 7.5", then it would be on the border line of acceptable. Correct?

I realize that splitting a piece of wood this small will not give an accurate split line, but I use it for discussion.
Thanks for the help.
James

Ed, That long stock will not fit in a flat rate gameboard box and weight based rates are used. It weighed 17lb 15 oz.[18# ]Good thing we use USPS, because UPS would have been double the cost, or more, and slower service., In which case I'm sure you would have to say, "Forget that!"

Since cutting tonewood product is our business, I can shed some light on the fiber. It's really a bad idea to split braces, it's a terrible waste of wood. Here is why. Do you know what split tapers are in cedar or spruce shakes? They are produced from the straightest fiber logs. It happens, because the fiber rips and jumps growth lines as it splits the length. one starts with a 1" split with the froe and it tapers to maybe 5/8" at 24" length, then the block is flipped over and a taper is split from the other end.
However when the block is thick and the split is extremely fast, like hammer strike fast. BAM FAST!, there is less fiber tear. Wet fiber actually splits better than dry.. It is GREAT to see the orientation of the fiber, such as you get in split face brace stock, But at that point, it's best to saw parallel to that face and avoid tearing fiber to then cause work and waste cleaning up.

So if one buys split stock from you, what's your suggested process to turn it into braces?

Regardless if one purchases sawn bracewood stock or split face bracewood stock, and whether they purchase the flat sawn sort of the more common VG cut sorts. I would think making a GREAT part with it less work and best recovery from material, to be the common goal. I don't know how you make your braces. I have never made a one. We don't build guitars. Some customers take billets and cnc carve a profile, and then I believe rip the shaped braces from the billet on a table saw or other., and maybe some use CNC to do it all. It sounds like some cut a dimension stick from the billet and shape it. Whatever the process, I would suggest just resawing to specific dimension from the billet, either shaped or not..following the orientation of the fiber of the split face, or just trust the sawn face. if using sawn bracewood stock. Even sawn bracewood far exceeds the very stringent technical physical strength requirements/specs. of Aircraft wing spar material.