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I'm working on a new bridge design. It will have a back-tilted saddle. I'm thinking 10 degrees back. I've never done one of these before. I'm debating whether to rout the saddle slot before gluing the bridge on or after. I'm sure I can come up with a jig to rout the back-tilted slot after the bridge is on, but I must admit I find the idea a bit daunting. It would certainly be much easier to do it on the router table as I'm making the bridge. But I like the idea of precisely locating the saddle for best intonation on all strings (perhaps avoiding an unnecessarily wide saddle) after the bridge is on. I wonder if any of you who tilt your saddles back rout the slot after the bridge is on, and, if so, if you might give me a little encouragement and perhaps a suggestion or two as to how to do it as simply and efficiently as possible.

Thanks! Stay tuned...another related topic post to follow...

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Thanks for your reply, Hesh. I'm not at all set on making my own jig. As a matter of fact, in a fit of tool-buying a while back, I got the stewmac jig, but haven't used it yet. So far, I've done saddle slot routing before putting the bridge on.

I'm not sure what "legs" you're talking about. I also haven't really looked at what modifications would have to be done to this jig to use it with one of my laminate trimmers rather than a dremel, which is something I would want to do - I don't trust a dremel to cut a clean and accurate slot.

My understanding of the back-tilted saddle idea is that it puts the down-bearing force of the strings more in line with the vertical dimension on the saddle, because of the way the strings break over the saddle as they go down into their anchoring points (in my case, it's a pinless bridge, but the angles are similar to a typical pinned bridge). The energy of the strings then goes more directly down to the floor of the slot rather than into the front wall of the slot. It's been said that this difference is especially noticeable with the use of an under-saddle pickup... better response. It makes intuitive sense to me that it would improve, however slightly, acoustic response as well. Even from a purely structural standpoint, it makes intuitive sense to me that it's better to have the strings pushing the saddle straight down into its slot than tending to pull the saddle forward.    

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

just stick a ship on the underside of your router base.

I know Paul Woolson is doing this on his bridges. Maybe he will share his methodology.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

I use a saddle with about 7 degrees of tilt to it. I usually put pickups in my guitars and it helps a whole lot there! It also gives you an added benefit of helping with the intonation, since the higher you raise the action, the more the saddle tips back, and the other way 'round. To me, it has lots of positives and no negatives.
I route the slot before I glue the bridge on, and I made a jig that holds the bridge and use a router table to cut the slot.

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Mark Swanson
Swanson Guitars
http://www.MarkSwansonMusic.com

I put about 4 degrees back tilt on my saddles for all the reasons mentioned above. I broke down and bought a small milling machine from Grizzley. It sure does give you control.

Go to the Santa Cruz Guitar forum
and read all about backward canted/sloped/angled saddles as now done on their guitars. Lots of input and fact direct from the boss, Richard Hoover.

http://santacruzguitarplayers.com/forum/viewtopic.php?t=300

Interesting.........I have a 1991 Gibson Nick Lucas Special Reissue. I notice that its saddle has a definite tilt, but towards the nut. It appears to be built that way, the slot looks like it was cut at an angle. Seems like there's different opinions about how to do these things. Anyone know about Gibson's?

CrowDuck

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Chris Nielsen
Soquel, CA.

[QUOTE=crazymanmichael] just stick a ship on the underside of your router base.[/QUOTE]

I suppose it could be just that simple, but I'm still having a hard time visualizing how I'd plunge the bit into the bridge with precise control unless I had some sort of carriage that supported the router base in this tilted position as it's lifted up and lowered down for the plunge. Plus, it seems like it might be tricky to design such a table and carriage set up to sit on top of the guitar that wouldn't then have the router base up to high off the bridge (the tilt adding to that height). It's entirely possible that I'm making a bigger deal out of it in my head than it needs to be. It's just the way my mind works that until I can visualize something pretty clearly, it's hard for me to design it. Probably I should just start playing around with possibilities on scrap. Or forget about it and just rout the slot on the router table and trust that I'll get the compensation close enough and have enough wiggle room on the saddle to dial it in just right for each string.

Now that I think about it, though, however I rout the slot, I guess I'll have to take the back tilt into consideration when measuring the compensation, since the front edge of the slot will no longer be the front edge of the top of the saddle. That would seem to add an extra measure of guesswork - maybe another reason to plan for a wider saddle, at least until I've done a few of these and get the feel of it.   

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Hey Todd;
I agree with your last paragraph emphatically. I was going to mention it, but you came to the realisation before i got around to it.
With a narrow saddle you might be limited when lowering the action sometime down the road.
The tilt back sure seems like a good idea, both structurally & for efficiency of energy transfer into the top.
I hope you'll update us as you go.

[QUOTE=Todd Rose] [QUOTE=crazymanmichael] just stick a ship on the underside of your router base.[/QUOTE]


Now that I think about it, though, however I rout the slot, I guess I'll have to take the back tilt into consideration when measuring the compensation, since the front edge of the slot will no longer be the front edge of the top of the saddle. That would seem to add an extra measure of guesswork - maybe another reason to plan for a wider saddle, at least until I've done a few of these and get the feel of it.   [/QUOTE]


Go read the link I posted re: Santa Cruz Guitars back angled saddle. Explains the reasons and what occurs when you have to lower saddle height later in life vis a vis string/scale length.

I read that, Hank, thanks. It didn't tell me anything I didn't already know, but I'm sure it was helpful to others who weren't already familiar with the concept of back-tilted saddles, and how they provide the extra benefit of self-adjusting compensation, as it were, when the saddle is lowered, so I appreciate you posting it.

What I was talking about in my last post was getting the intonation right in the first place - that when I'm positioning the bridge, and therefore the saddle slot (assuming I've cut the slot before gluing the bridge), on the guitar, I need to be thinking in terms of where the top of the saddle will be, not where the slot itself is. Since the saddle will tilt backwards, the slot will have to be slightly more forward then I would otherwise put it. That was something I just hadn't thought of until this discussion, and it made me think I'd give myself an extra margin of error, at least on my first few guitars with a back-tilted saddle, by giving them a wider saddle.

It's also, in my mind, another argument for routing the slot before the bridge goes on. As I see it, the advantage of routing the slot with the bridge on the guitar is that you can use mock saddles of some sort to mark the ideal peak point for each string, then rout the slot very precisely using those marks as a guide. But since the saddle is going to be tilted back, I couldn't use those marks directly anyway; I'd have to put the slot slightly forward of where the marks would indicate. The inherent imprecision of that, as I see it, defeats the purpose of doing that method. Might as well just rout the slot first, use a wide enough saddle to give myself plenty of wiggle room, and make my best guess as to where the slot should be as I'm positioning and gluing the bridge. Then I'll do what others do to mark the precise peak points for each string on the saddle itself, and shape the saddle accordingly. I'm confident that in the end, I'll get it spot on with that method. After doing a few of these, I'm sure I'll get a better feel for it and be able to make narrower saddles if I want to.

I think I've come to a decision on how I'm going to do it, thanks to all your input... but if anyone else who does back-tilted saddles wants to jump in with comments on your methods, I'd still be glad to hear them. Thanks!       

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Maybe a little late, but:

I don't beleive the tilted saddle effects the acoustic sound of the guitar any, so long as it's a stiff material, like bone, and it's fitted properly. You were going to do that anyway, right? It does seem to help the sound of a UST. It also helps minimise pressure on the front of the slot that would widen the slot over time, and eventually break the bridge.

I rout the saddle slot on my drill press, using it like a milling machine, as one of the first things in making the bridge. I locate the bridge on the top by clamping it in place and measuring carefully, then drilling the outer pin holes in the top to use as locators. If you are looking for the last word in precision, why not make a saddle of about the right height and put that in the slot when you're measureing for the bridge location? Then you'll _know_.

Ok, I'll ad my two cents here.
First, if it's possible, I respectfully disagree with Alan about it affecting the sound. I did an apples to apples comparison with the only thing being different was that one had a straight saddle and one angled at 8?. I noticed a big difference in volume, the angled saddle was noticably louder. This is a by-product of why I started angling them in the first place. I was only after the structural effects. My theory behind this, and it's only theory as I don't have the scientific mind like Alan, is that the pull of the strings force it down into the slot rather than waste energy trying to twist it out of the slot.
As to how I make them, I do it prior to glueing them on the top. I wrote a pretty indepth article in AL (AL#79 p. 46) which might make things more clear. But basically I angle the bridge up at 8? and then route the groove. With a plunge router I think it makes more sense to angle the piece and keep the router verticle for lowering. This might be kind of tricky if it's on the guitar.

I understand what Paul is saying, but being that I'm not sure how his experiment was done, and there are so many variables involved in why he achieved different results that it is hard to quantify those results as being strictly attributed to the angle. That said, I used to angle my slots to 7.779 degrees. Ok, kidding...about 7 degrees though, because the *theory* is that it helps with under-saddle pickups, by vectoring the forces more perpendicular to the break angle. It should make a difference in sound, but how much is hard to quantify. I no longer do it because mostly I have switched to using K&K pickups.

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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 just made a quick sketch with a sharp pencil to see what dimensions changed. Assuming a 5/16" thick bridge (like on my SC OM), and a saddle that is routed 3/16" into the bridge and stands above the bridge 3/16" (again what's on my OM which is now 16 years old) then the 10 degree tilt back takes the leading edge of the saddle BACK just a bit shy of 1/16" .

One could therefore either adjust the initial placement of the bridge that much at the leading edge of the slot, or, as mentioned, have a dummy saddle at close to finished height, and use it in the bridge for the locating measurements.

My hat would be off to anyone who could consistently place a bridge to perfect intonation without further tweaking of the saddle after the fact...ramps to adjust string lengths for intonation. Heck, even Taylor, the most "roboticized" big boy, can't nail it perfectly and uses a compensated saddle for at least the B string.
And over time, even the most perfectly placed bridge is going to need saddle adjustment as the guitar settles in and adjusts to it's owner and the climate it resides in.

As for the sound/tonal benefits, that will be in the ear of the beholder. The added strength, or reduced stress, of the saddle in the bridge proper certainly has long term value, but could also be gained by just having a tad more bridge material in front of the saddle slot and staying with a vertical saddle.

Anyways...a million ways to skin the cat, or in this case build the guitar

[QUOTE=Don Williams] I understand what Paul is saying, but being that I'm not sure how his experiment was done, and there are so many variables involved in why he achieved different results that it is hard to quantify those results as being strictly attributed to the angle.
[/QUOTE]
Sorry Don and others. I neglected to give the details of this experiment. Same guitar, two different bridges. Exact same shape and size, just the angled saddle was different. Same glue and everything. Apples to apples as close as I was able to do so. I did indeed hear a difference.

[QUOTE=Alan Carruth] If you are looking for the last word in precision, why not make a saddle of about the right height and put that in the slot when you're measureing for the bridge location?
Then you'll _know_.[/QUOTE]

Great idea, Al. Thanks! Thanks, also, for your thoughts on the acoustic effect, or lack thereof, and structural effect.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

[QUOTE=Pwoolson] I did an apples to apples comparison with the only thing being different was that one had a straight saddle and one angled at 8?. I noticed a big difference in volume, the angled saddle was noticably louder.
I wrote a pretty indepth article in AL (AL#79 p. 46) which might make things more clear. But basically I angle the bridge up at 8? and then route the groove. With a plunge router I think it makes more sense to angle the piece and keep the router verticle for lowering. This might be kind of tricky if it's on the guitar. [/QUOTE]

Paul, thanks for sharing the results of your experiment. I hope this proves to be true on my guitars as well.

Thanks also, for referencing your article in AL #79. I remember seeing that, now, and have gone back and read it again. I think I'll be doing mine on a router table, but I still appreciate learning about your ideas and methods.

As for using a plunge router on a bridge already glued to a guitar, that hadn't occured to me. When I was talking about plunging the bit into the bridge in my post above, I was just thinking of tilting the router up and bringing it back down. Actually, the idea of using a plunge router base makes it easier for me to visualize a jig for doing it with the bridge already on the guitar. Still, I think for now I'll do it on the router table.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

[QUOTE=HankMauel] I just made a quick sketch with a sharp pencil to see what dimensions changed. Assuming a 5/16" thick bridge (like on my SC OM), and a saddle that is routed 3/16" into the bridge and stands above the bridge 3/16" (again what's on my OM which is now 16 years old) then the 10 degree tilt back takes the leading edge of the saddle BACK just a bit shy of 1/16" .

One could therefore either adjust the initial placement of the bridge that much at the leading edge of the slot, or, as mentioned, have a dummy saddle at close to finished height, and use it in the bridge for the locating measurements.

My hat would be off to anyone who could consistently place a bridge to perfect intonation without further tweaking of the saddle after the fact...ramps to adjust string lengths for intonation. Heck, even Taylor, the most "roboticized" big boy, can't nail it perfectly and uses a compensated saddle for at least the B string.
[/QUOTE]

Hank, Thanks for taking the time to do that sketch. That makes a good reference point. Using a dummy saddle while locating the bridge, though, is the best idea I've heard yet.

Just for clarity's sake, I never imagined making a saddle that would not be tweaked after stringing up to dial in the best intonation for each string. My thinking on being as precise as reasonably possible on the locating of the saddle slot is just to have the outline of the slot, or, rather, the outline of the top surface of the saddle, closely encompass the ideal peak points for each string, so that the saddle needn't be unnecessarily wide. Actually, I'm not sure a wide saddle is such a bad thing, but it does seem that it would add a bit of unnecessary mass to the bridge.   

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Paul:
Thanks for posting on your experiment. Just to dot all the i's and cross the t's; did you weigh the two bridges? Check the stiffness/resonant frequencies of them? Was there any change in the top modes before and after? Yeah, I know: too much to think of in a 'simple' experiment. ;)

Your theory about why you got the effect you did makes as much sense as anything I can think of. I'd be willing to bet that that any differences between the two bridges _other than_ the saddle angle were minimal, but it's nice to _know_.

I've been looking at strings for about a year now; it's time to start thinking about bridge experiments. Let's see if I can come up with a quick way of altering the saddle angle without swapping the whole bridge....

BTW: I _know_ that changing the angle of a violin bridge makes a huge difference, but that's another beast in many ways.Alan Carruth38750.6684606482

Rats! I knew your scientific mind would catch something. No, I didn't think to do any of those things. They were however both ebony and cut on the same jig so, in theory, they were exactly the same size in all dimensions. So my guess is that weight and deflection were very minimal.

One more thought to throw into your equation, Todd. What angle do you use when routing the saddle...1st to 6th string "set back"?
I use a 5 degree angle (off the straight front face of the bridge blank) and find that I come pretty close to getting an initial "good" intonation. When I build with a 25.4" scale, I add about a sixteenth of an inch to my "scale" on the 1st string when I place the bridge...so it's 25.4 +1/16"..if that make sense. It leaves only minor initial ramping to get on the intonation, although as the guitar settles in, there will probably be more "adjustments" needed.
Oh, and I use a 1/8th wide saddle. The difference between that and the 3/32" (like Martin) in negligible and does give you a bit more saddle "meat" to work with for adjustments.