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So..... I have had my stewmac saddlematic setup as I thought was correct according to videos, etc. I have been studying a guitar I built a few years ago. High e is spot on for tune and intonation. The rest tune well, but intonation measures high. Looking at saddle string marks, there does not appear to be much room to move contact point towards rear of guitar (to lower intonation).

So, I'm at a dead end. First, what do you recommend to fix this? Saddle is thin 1/8" Not much room to move backwards. I'm ok with reslotting.

Second, clearly my saddlematic is not set up correctly. With those curved points, its difficult to get it right. Does anybody have some kind of measurements that are solidly referenced that anyone can use?

Mike

The stew Mac fret calculator seems reliable, and includes compensation suggestions...

I made little shims to set the pointer on the saddlematic. I found it impossible to try to measure and set it.

The instructions for the saddlematic say that with the recommended settings the pointers indicate the front edge of the saddle. Perhaps back then you routed the slot with the pointers as the center of the slot?

If it’s ebony I would just reroute after filling. I tried to widen an existing slot once and that was a disaster.

Brad


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Just had a thought... gonna see if I can measure a diff way

You could try trimming a small amount off the nut end of the fingerboard to give it a little nut compensation.

So, I lined up some paper with back edge of saddle-matic on a scrap fingerboard. Used a pencil to trace front edge of saddle-matic. Then pressed points into paper. Both of my saddle-matics are well set according to stew-max (1/16, 5/32). Why do I have two? Because can't seem to keep track of them in the shop move.

Anyways, I remeasured slot with "calibrated saddle-matics" and its clear I screwed up. Poor bridge placement. Only 1/16" error, but is enough. Owner has agreed to a reslot at my expense, glad to do. Its a cocobolo bridge, but I am confident I can hide it well.

Btw, I recommend this measurement method to assure yourself that pins are properly spaced. Looking back in my records, I built this guitar at the same time I was building a left handed guitar. I'm sure messing with the pins to work with south paw guitar caused this.

Here is a simple jig I use for slotting bridges that are glued to the guitar body. I have also used it to widen slots. The pencil lines are marks to show when front edge of the base is at the end points of the rout. A more complete explanation is on the MIMF in the Wood and materials section.

Once you’ve determined that you’ve got a bridge in the right spot, you can reverse engineer a bridge placement jig that indexes off the saddle position.

I’ll show you my system in the morning. Allows you to only do the thinking once.

^^^^ Same. I have an acrylic template I made that registers in the nut slot and is cut off a the front edge of my saddle, at the correct angle. I agonized over the first one, using the plans as guidance, and once that worked I made the template and never thought about it again. This, of course, assumes you make the same model multiple times. FYI.. I use wide saddles and file each take-off point individually per string once the guitar is strung up.

Just two days ago I used a Saddlematic for the first time. I agree that setting the distance for the points is a nuisance and a mystery. What I did was measure the thickness of the straight shank of the wire, subtracted half of that from the distance S/M suggested the point needed to overhang the end bar and used a stack of feeler gauges to offset the wires from the bar that holds them, there being two different distances.

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Peter Havriluk

Just two days ago I used a Saddlematic for the first time. I agree that setting the distance for the points is a nuisance and a mystery. What I did was measure the thickness of the straight shank of the wire, subtracted half of that from the distance S/M suggested the point needed to overhang the end bar and used a stack of feeler gauges to offset the wires from the bar that holds them, there being two different distances.

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Peter Havriluk

With Stew-Mac’s fret calculator in one hand and a 36” PEC blem rule that measures in hundredths in the other, you’ll never look back.

Although I’m really interested in seeing Ed’s jig.


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I’ll share an idea that I have not yet tested, but I like it a lot:

The center line finder from Luthier Suppliers has an add-on block that aids in squaring the bridge to the center line. It clamps to the center line finder with a thumb screw. But a person could make a slightly different version of that screwed on block, one with a saddle slot at the proper angle, and a slot width matching the slot in the bridge that needs placement. You could put a very tall saddle in the slot on the jig block, use the same 1/100” rule James just mentioned to find the perfect location of the jig block on the center line finder, then put the jig on the guitar and the bridge mated up with the extra tall saddle that is in the jig block. All the measuring happens on the jig before putting it on the guitar, and since the bridge is locked on the saddle, and the saddle is locked in the jig block, and the jig block is locked on the center line finder, and the center line finder is locked on the guitar, it should be less prone to scootching around.

As I said, it’s an untested idea, so be cautious in experimenting with it. I know I will.

Hi Don,
For some reason your post reminded me of a song

Dry Bones:
https://www.youtube.com/watch?v=cLi55MV04a8

So here’s my system. Remember, the locating jig is reversed engineered off a tested, accurate guitar.

First step is to route the saddle slot (4mm back angle over 71 mm, which works for the TUSQ saddles I use)

Then the bridge pin hole drilling jig etc locates into the saddle slot. This ensures that the saddle slot and bridge pin relationship is a constant, so that when you correctly locate the saddle slot, you are correctly locating the string path as well. No more eyeballing with taped down strings or straightedges.





Next, make a tapered jig that follows the contours of your fingerboard taper. Make it start at the nut and extend a few inches past the bridge location.

On the guitar that is known to be accurate, make a dummy saddle that fits much looser that an actual saddle. Loose enough to fall out if you turn the guitar over.

Sand it so the top is flat and sits above the bridge about 1mm.

Put some medium or gel ca carefully on the saddle top (don’t get it on the bridge, lol). Place your tapered jig so it aligns with the fb and hold it down firmly on the dummy saddle top.

When the CA takes, lift out the dummy blank and voila! Not you can locate your saddle and pins off the dummy saddle jig without measuring.

On mine, you can see how there’s a fretslot template. Before I use it, I pop it on the frets and it locks in. This prevents using the wrong scale jig.

If I were to make it again, I would slot the bottom of the jig so that the back and forth location registered off the frets. For now I just feel that it’s flush with the nut end of the FB.

Anyway, I like this system cause you can measure everything very carefully, get it exactly right, and then never have to think about it again. Cause the answer is the same every time...



Hope that’s helpful!


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Ed--

That second jig looks a lot like what I was talking about above. Glad to see that I wasn't crazy. At least not based on this evidence . . .

Lols. Easy, cheap, fast, accurate. Everything I like in a jig!

Brilliant.

Here’s my take on a saddle/bridge jig.
One end snug in the saddle slot, the other in the nut slot.
Its been very accurate for me. Took a few attempts to get it right on.
Of course its only good for 1 scale length

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My memory is so good, sometimes I remember things that never happened.

This is just pinched from my time at the Larrivee shop...