The fake through-saddle bridge: stronger than vintage
Issue 26 April 19, 2007
This bridge has two big problems:
- The saddle’s too far forward for proper intonation (the guitar plays sharp)
- It’s got too much hardware on it. The thumbscrews and metal saddle support are tone-killers.
I made a new bridge with some trickery, and now this guitar sounds lots better.
Here’s how I made a fake through-saddle bridge:
A “through saddle” is a wide, vintage style.
The wide saddle extends out into the carved wings on each side of the bridge. I like this look, but such a long saddle slot weakens the bridge — because it removes so much wood. This bridge looks like a through-saddle, but it’s not: it's a fake I made using the technique I'll show you here.
Here's why it's called a through saddle: the saddle continues through the raised middle of the bridge, and out onto the lower side wings.
The problem: weak bridges
Take a look at this 1951 Martin D-18. The bridge is split entirely, because the slot was too deep and too close to the front of the bridge. I’ve seen quite a few like this, and my “fake through-saddle” technique is how I avoid sending more of ‘em out into the world.
Here’s my secret:
I made a saddle with a tab in the center that sits in a typical saddle slot. The wings on either side are just for show — to make it look like a vintage through-saddle.
My fake through-saddle is this shape: The center installs like a typical saddle and the "wings" are just for looks.
This was important in this case, because a low neck-set angle meant it this guitar had to have a low, thin bridge. Thin bridges don’t have much wood for deep saddle slots, so a real through-saddle would be especially weak. I’ve used this technique for years on vintage Martins and Gibsons. It looks and sounds great without weakening the bridge.
With the new bridge dry-clamped in place, I strung it to pitch and used my Peterson tuner and the Intonator to find the correct saddle position. Two bridge bolts hold the bridge in place, and since this is such a wide, thin bridge, I added a pair of mini cam clamps to secure the wings.
I also moved the bridge pin holes on this guitar, to get a better string angle over the saddle. No room here for this part of the story, but it was the BridgeSaver that let me quickly patch all six old holes before drilling new ones.
Usually, I cut the saddle slot after I glue on the bridge, but this time was different: I’d just made this bridge on the Luthier's Friend Sanding Station, using a plywood pattern to hold the bridge while I shaped it (the subject of a recent Trade Secrets). Today, I continued this approach in cutting the saddle slot.
The plywood pattern has two 3/16" wood dowels pegged into the bridge’s E-string pin holes. This gives me a substantial chunk of wood to hold onto when working on the bridge. With the bridge on this pattern, cut a saddle slot running at a typical 4° angle, with the treble side angled closest to the neck.
I made a 4° tapered wedge and double-stick-taped it to the front of my bridge-shaping pattern. With the wedge in place, I cut the saddle slot using my drill press and a 1/8" carbide downcut bit by simply sliding this assembly along the fence of the Luthier's Friend.
My first slot was the full-length through slot, but I only routed it deep enough for the ends of the saddle to extend into the curve of the bridge wings. Then I lowered the cutter and deepened the slot in the center to accept the tab in the middle of my fake through-saddle. In the photo you can see that the cutter bit is down in the middle section.
Using a thin piece of maple (quick and easy to cut), I made a template that fit the saddle slot. I traced its shape onto a bone saddle blank, clamped the blank in my vise, and went to town with saddle shaping files to notch the ends.
Here I’m set up to feed the pattern-mounted bridge into the sanding station to shape the ends of the saddle, making them curve smoothly down to meet the shape of the bridge.
I mounted the pattern onto a scrap of plywood in my repair vise while I smooth the tapered ends with a scraper.
Along with this new bridge, I gave this guitar new frets and a bone nut. This makeover turned a so-so instrument into one that sounds really good!