Making bridges for vintage guitars using minimal tools
– a layman’s approach (Part 4).

I’ve approached this subject in 4 separate posts.  It’s necessary to first read the Introduction post, Part 1, or the other posts (Parts 2, 3 and 4) may not make much sense.

Part 1. Introduction, tools and a jig.
Part 2. 20th Century pyramid style bridge.
Part 3. Truncated pyramid style (or Chicago) bridge.
Part 4. 19th Century pyramid style bridge.

Part 4.  19th Century Pyramid Style Bridge.

A  pyramid bridge from the 19th Century is characterized by the elongated pyramids on the ends.  Used on 1800’s Martin and Bay State guitars plus others.

Keep in mind that pyramid bridges can look very different from maker to maker.  You can also buy a ready-made pyramid bridge online from Stewmac.com and others, but I like to tailor-make them.  There are other sites online showing how they make a pyramid bridge, but once I’ve made the jig to cut the valleys, the bridge is relatively easy and quick to make, and the results are accurate. Because they are all hand made with minimal electric tools, it gives me more control and I have very few rejects.

This 19th Century style pyramid bridge I am making here will be a stylized version of the 19^th century pyramid bridge for a beautiful c.1890’s Bay State Grand Concert guitar I have.

I’m making a stylized version of the original bridge because:

• Originally the Bay State guitar would have had gut strings and I want to set it up with light weight steel strings. I think the width of the bridge needs to be a bit wider than the original 7/8”,
• This guitar has already been somewhat ‘hot rodded’ (with X-bracing and modern frets) and setup as a ‘playing’ guitar rather than a collector’s guitar. So, I’m not trying to copy the original bridge exactly, but I do want to pay homage to the original bridge design. (There was quite a bit of damage with multiple splits in the soundboard, that once again limits its’ value as a collector instrument), plus
• I’ve never made this style of 19^th century bridge before, so it probably will look a bit different than the original anyway!

Marking the bridge design on the blank

I’m using an existing Bay State guitar bridge as a guide for the general shape of this bridge.

The ½” (12mm) diameter rod is very close to the curve on the ‘valley’ of that bridge.  I narrowed the gap for the rod on the jig from 5/8” to ½” by dropping a box over one of the guide blocks on either end of the jig.  (I could have just as easily screwed the guide blocks onto the main board from underneath and moved one of the blocks closer and re-screwed):

I mark out the measurements on the blank:

(The ½” ‘valleys will finish a bit wider because of the added thickness of the sandpaper wrapped around the ½” rod).

Positioning the Bridge Blank on the Jig

Once the ‘valley’ positions are marked out I position the blank in the very center of the jig, with one of the valley positions under where the rod will be, as I did with the other style bridges:

If I want the valley floor to finish 3mm from the base of the bridge,  I screw 3 mm ply strips either side of the bridge in that area.  It means when I sand down to this I have the correct depth of the bridge.

When the bridge blank is held in place, and before the ends are put on, it’s good to wrap one of the sandpaper strips around the rod and run it back and forth a few times to make sure it starts sanding in the middle of where I’ve marked the valley.  The bridge position on the jig can be moved up or down a little if needed before screwing on the end strips that hold the bridge tight into position for sanding.

Sanding and Filing

Once the jig is screwed onto the workbench I sand back and forth with the sandpaper strips wrapped around the metal rod (the rod moves too), starting with the coarse paper that does most of the cutting, then moving down to the smaller grit papers.  Using a  1000 or 1200 grit paper at the end will give a mirror finish.  All in all, sanding both valleys on the bridge only takes a few minutes.

Once the 2 ‘valleys’ are cut it’s time to shape the rest of the bridge.

If you have a belt or disc sander this can be also used but extra care needs to be taken, one slip and the bridge is ruined. (Filing takes a bit longer but is safer):

After filing and sanding the pyramid:

Shaping this bridge

As I mentioned, this is the first bridge of this style I have made.  Fortunately, I have a small Dremel-like hand drill that I used to help shape this pyramid:

After some smoothing I get to this:

Then to shape the main body of the bridge I use the profiles of the existing Bay State bridge as a guide:

Shaped with a file and then sandpaper:

Because the ebony was not really dark I added some black wood stain at this stage, then polished with the finest sandpaper I had and then 6000 Micro Mesh (see TIPS at the end of the post.  The result:

 

Routering this bridge for the Bay State guitar saddle.

This is something I don’t tackle myself.  My luthier friend, Matt, from Matts Guitar Service (see CONTACTS page) is doing this for me here.  I’m not game, one wrong move and the bridge is ruined!

The bridge has now been glued onto the guitar and this photo shows placement of the saddle with a pencil line.  For a guitar with 12 frets to the body I’m told the placement from the nut is twice the distance from the nut to the 12^th fret plus 2mm for the tenor end, and plus 4mm for the bass end of the saddle.

First photo shows Matts custom made plexiglass jig clamped onto the guitar with the router. The jig is then positioned so the router follows the saddle line when the router is run along the plexiglass (perspex) guide-rail. Then the next photo shows the jig clamped into place and routering.

And the final result:

(I’ll do a separate post about this guitar soon when it is finished and set-up).

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Some other guitar bridges I have made:

(Repeated from the end of The Introduction: Part 1).

Well, full disclosure, I didn’t make the bridge on the last guitar, the 1930’s-40’s Harmony with the birds eye maple bridge.  Made by my friend John Davis from The Guitar Repairers, Brisbane (see CONTACTS page).

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End of Part 4;  Links to the other posts about this subject:

Part 1.   Introduction.
Part 2.  How to make a 20th century pyramid style bridge.
Part 3.  How to make a Truncated (Chicago) style bridge.
Part 4.  How to make a 19th century pyramid style bridge.

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