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I read an old post by Rick Turner that said the following:



Do you agree? (note: I'm asking about the bridge, not the bridge plate)

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Formerly known as Adaboy.......

That actually does make sense to me.
The strings would be against the hard grain structure.
Interesting!
One more thing to think about.

Strange, I thought
Peghead.........neck............body..............////////.............tail
would maximize the strength of the bridge in front of the saddle slot, which I see as (admittedly intuitively) the point of maximum stress
and not
Peghead.........neck............body..............\\\\\\.............tail
where I would think the stress is tending to separate the growth rings - ????
Someone correct me by all means, I've just made a bridge "my" way and will be fitting it soon!

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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.

There is missing information in that diagram to know exactly what Rick wanted to tell us. Are we looking at the guitar from the face or from the side? It makes a big difference. If the diagram shows the guitar from the top, than I agree with him. if it's from the side, then either way it is prone to cracking, IMHO. What is important is that the grain lines are not in line with the saddle orientation or the bridge pin line.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

My guess would be we are looking at it from the side. If so then that is what I always thought would be the best assuming the \\\\\\ is the annular rings. Wen orientated as such the lines compress at the top, the thinnest part of the bridge slot. I should say that I 'used' to think this way. Now I am more of the opinion that it doesn't matter so long as you slot the bridge and the ball ends are fit properly to the bridge plate.

I always make them the way Rick showed. It seems to me this way the saddle momentum compresses the grains together rather than trying to pull them apart. On the other hand I've seen a number of bridges made by very reputable classical builders were they were angled the other way. Or the wood was perfectly quartered (ughhh) or flatsawn.

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Build log

Good point asking if the view is from the side or from the top.

I'm guessing the view must be from the side.......and I'm guessing it must be from the player's perspective (everything is reversed if viewed from the bottom of the guitar). It's my best guess though and I didn't see where the perspective was questioned and cleared up in the original post.

So for this discussion, let's assume the view is from the side......viewed from the bass end of the guitar (the players perspective when if he looked at the end of the bridge). With that in mind, do you agree this is the best grain orientation?

And a followup question, if you had quartersawn bridge material, would you use it?

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Formerly known as Adaboy.......

Darryl: I think Rick is saying in a side view and I tend to agree with him. Rick puts out good info. More importantly to me is the type of saddle and how close it is to the front of the bridge. I think the old style through cut saddle slots result in the most split bridges. Even if glued. Also slots cut too close to the front of the bridge can give problems. I have tended to make smaller and smaller bridges and as a result am pushing closer to the front edge of the bridge with the leading end of the slot. Approximately .125"minus,but not sure where that fits as compared to normal. Bridge size about 1" by 6". As to using quartered sawn,I have and would again.
Tom

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A person who has never made a mistake has never made anything!!!

I agree. As long as the guitar is treated well, it shouldn't matter much. Also, if the guitar is rift sawn, it would be floppier along its length. Consequently, the bridge wings would be less efficient at transferring torque to the X-braces. Whether that matters at all, though, is a different question i suppose...

Still, I can see the point of making a guitar that can handle abuse, in case of unforeseen circumstances

Thanks,
Sondre

Split in two, never yet. But cracked, several times. On old guitars indeed (albeit younger than 50 years old...), but still within a normal lifetime of a guitar.

The cracks I've seen were always either in line with the bridge pins, or in line with the saddle slot.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Woops... What I meant, of course, was "if the BRIDGE is rift sawn" Please don't rift saw your guitars

I had one bridge split there. Luckily before I glued it; I was working with a chisel in the slot when the front simply fell off. It had little meat there (like you see on a Torres, that guy was crazy) and the rosewood was quartersawn. Never again for me. I now leave the front at least 5mm wide, and use rift (not a problem really, truly quartered bridge blanks are rare)

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Build log

I have one sitting here in my office. Split at the saddle slot (Not one of mine ). Indian Rosewood, grain in the opposite direction from the diagram.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I've seen several over the years. Usually they were perfectly quartered, and had the slot 3mm or less from the front edge. I started making mine of rift cut wood some years ago, before I heard about it from Rick: small minds in the same gutters. I have not worried too much about which way the rift cut goes, but I make the slots about 5mm back from the edge, which helps.

Another of Rick's Tricks that helps is to slant the saddle backwards. In theory, if the saddle bisects the break angle, there is no net tipping force on the top, and it will never split out the front of the slot. In practice, I use a nine degree slant, which goes some way to minimizing the tipping force, and also more or less automatically compensates for changes in action height. Smart fella, that Rick...

Thanks for the comments everyone. I wouldn't mind hearing other opinions on using quartersawn bridge stock. I have several quartersaw (or very near quartersawn) bridge blanks that are too small to be re-sawn with a different grain orientation.

Also, if slanting the saddle back at a 7 deg angle, do you think it's safe to start the saddle slot 1/8" from the front of the bridge? (rosewood bridge)

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Formerly known as Adaboy.......

If you're worried about your bridges splitting, a layer of CF will help you sleep better.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Any time you combine stress risers(slots or pin holes) with quartersawn rosewood, they are prone to crack. Rosewood is crackprone by nature to start with, so i would not use quartered rosewood for a bridge on my guitars for that very reason. I've started to not use rosewood at all for bridges because of it's crackprone nature. I would think that running the grain lines on an angle to the saddle slot would be the best if useing wood you are not sure of.

Has anyone ever use flat sawn bridges? I would think that you would reduce the chance for cracking, like a flat sawn bridge plate. Is the resulting flexibility in the wings that big of a variable on the tone?

Cracks tend to happen along the line of the medulary rays, which are weak places in the bond between cells within a given growth ring. A flat sawn bridge would tend to crack straight down, say, between the bridge pin holes, especially when wedged by tight fitting pins.

For starters, neither of you has a small mind....

A long time ago a repair guy in my area told me that the bridge failure thing he saw most was from having the saddle slot too far forward. Another aspect is the grain orientation and how the pin slots are laid out on the blank. Those that were in line with each other and the grain tended to give way.

The saddle slot that angles slightly backward also helps with getting a more firm pressure on the bottom of the slot should you have an under-saddle transducer in there. Rick's advice is right on target. Usually, the guys who are the most successful in the industry are that way for good reasons. I tend to listen to those guys when they speak...

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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."

Don Williams wrote:
"Usually, the guys who are the most successful in the industry are that way for good reasons. I tend to listen to those guys when they speak..."

Yup; if you're going to steal ideas, steal them from the best...

An idea is not "stolen" if the originator freely passed-on the knowledge, no? Rick freely discussed his ideas with us, so I never thought of myself as having stolen any of his(or anybody else's) ideas, but I do try to give credit if I can remember the source of the idea. And yes, sometimes we all come up with the same ideas, and it's only when one mentions it that we're reminded that we do something similar.

So to that extent, I'm no longer certain if the original idea of tilting-back the saddle was Al's or Rick's or mine(or all of us), but I began tilting-back my saddles in the late 90's. Not for added strength or to help under saddle pickups(ughhh), but simply in an attempt to have the saddle "self-correct" the intonation if we raised or lowered it. I ended-up with a (methinks? it's built-into my saddle slotting jig, so I don't even have to think about) 8 degree tilt.

As for split bridges, well, they happen. Chose your wood carefully, try to design it wisely, and offer a warranty. Some will split... A few years ago, I had what seemed like a lot of bridges that were failing in front of the saddle. I hadn't changed the design of my bridge, so after a few reports of breaks, I went and looked at my bridge stock. I had begun using bridges all cut from the same batch, and it turns out that this particular batch of blanks were all rather weak. A simple "destruction" test with a couple of rough-cut "dummy" bridges showed that these blanks would consistently break at less than half the "pull" it took to take most other blanks to failure. Problem solved! I haven't had a split bridge since(I believe).

A month or two ago, the original bridge on my 1951 Martin 000-18 split and broke-off completely at the saddle. It had held solidly for over 60 years, then without warning, snapped. I just happens. Gotta love wood...

You know, now that I think of it this pattern \\\\\\\\ viewed from the top does seem to have some good sense to it. That way your saddle slot is not on one particular plane and your bridge pins are isolated as well.

grumpy wrote:
"An idea is not "stolen" if the originator freely passed-on the knowledge, no?"

Yes, Rick did share that one, and many such ideas are pretty freely passed around among North American luthiers. It's one reason we've come so far in the past thirty years or so.

There are always ideas that are just 'floating around', and seem to be adopted by a number of folks more or less at the same time. My old partner and I discussed the problem of necks shifting, and came up with the idea of using an 'A' brace inletted into the neck block to cure it. Later I heard about the Martin patent. I'm pretty sure I started using this before they took their patent out, but, at any rate, I know it was an independent invention.

Short of taking out a patent, and defending it strenuously, I'm not sure how you could retain intellectual property rights on most of this stuff: keep people from 'stealing' these ideas. I remember Chris Martin musing at a convention once that it would have been nice if they'd taken out a patent on the Dreadnought shape, but then somebody pointed out that it would have lapsed by now anyway. Still, they might have made some money while it was in force.

Anyway, the real import of what I said was simply that there are a lot of good ideas out there, and it pays to keep your eyes and mind open. Often it's the best makers who seem to have more of the good ideas, so it's wise, as Don says, to pay particular attention to what they're doing.

Should I make a surrogate saddle to locate a bridge with a tilted saddle slot? Should it be located to the front edge of the saddle or the middle? Does the .020" that I removed from the nut end need to be factored into total string length? Thanks.

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Good judgement comes from experience. Experience comes from poor judgement.