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10 steps to a simple, easy-to-make maple bridge


Several of the other bridgemakers (see the links on the main bridge page) have included instructions and hints on bridge construction. Here are a few steps of my own in making a good-sounding bridge.

These bridges can be made using simple tools, such as a coping saw, hand drill, files, and sandpaper. I want it to be easy for musicians to make their own!

Bridges sound fine when made from several different kinds of maple, and will work and sound good on a wide variety of mandolins.

Any mandolin bridge illustration on this website may be used as a pattern. The line-art illustration at the top of this page, showing a 11-hole bridge, is especially intended to use as a template. This a good-sounding and reliable design which I recommend that you use for any bridges over 3/4" high. To download a bridge template, just click here, and then print it out.

For bridges less than 3/4" high, I recommend a 6-hole bridge. A template is here.

For bridges much lower than 3/4", I suggest that you adapt a 6-hole design to fit the shorter vertical space you have available. For flat-top mandolins I have adapted this design to bridges as low as 3/8", and obtained much-improved sound from those instruments. The holes can be as small as 1/8" on a very short bridge, and the sound will still be good.

Best length for a mandolin bridge seems to be between 4" and 4 1/4" long overall. Longer or shorter bridges seem to lose sound.

A mandola bridge template is here.

A mandocello bridge template is here.


Three stages in bridge construction:



Here's a strip of maple, a little over 5/16" thick, with a bridge template pasted right onto the wood. I often paste 4 or 5 templates on a strip if it is long enough, and make that many bridges at a time:




A typical bridge with the cutouts made and rough-shaping done:




Now here's another typical bridge, with the feet fit and the top cut to height, ready for the compensation cuts
and final installation:





Now, how do you get there? Here is a list of the bridgemaking operations, suited to the use of small hand tools. If you have a band saw or scroll saw and a belt sander, you will go faster, but take the steps in the same order:


1. Obtain a strip of hard maple, at least 4" long, 1 1/4" high, and 1/4" to (preferably) 5/16" thick. This can be American or European maple, slab-cut or quarter-sawn. The bridge will work fine with a variety of different maples as the raw material, although quarter-sawn maple is preferred. Ideally:

For an f-hole mandolin, European maple is preferred for richness.

For an oval-hole mandolin, American maple is preferred for clarity.

(Click here for a discussion of grain direction.)


2. To make an 11-hole bridge (the design at top, which I currently recommend), print out the picture with the bridge about 4 1/4" long, and paste it directly on the wood as a template (Thanks to Mike Conner for this hint).

If you need a taller bridge, just allow more material at the top of the template. If your mandolin needs a much lower bridge, try to cut the blank so that the line of holes will be about at the center of the finished bridge.

If you want to design a different bridge, simply draw the design of your bridge right on the wood, first in pencil, then in ink. I encourage you to experiment with new bridge designs, but I also urge you to make a regular 11-hole bridge at the same time and compare its sound with your experimental bridge. You may discover a new, good-sounding design!


Follow the template everywhere except for the feet. USE YOUR OLD BRIDGE to mark the feet for your new bridge, and make the inked line as precise as you can. Mark the outer 1" or a little more of each bridge foot, and then mark the space between them for a gently curved cutout, as seen above. I recommend that you make the bridge feet no more than about 1 1/8" long, and the bridge a total of 4 18" to 4 1/4" long.


3. Make the internal holes and other cutouts. For this design, these are 3/16"" holes. The hole centers are marked on the template.


4. If you are making a winged bridge, make any saw cuts now. The center cut will require a coping saw or jeweler's saw. The 11-hole bridge design should not have any side "wing" cuts.


5. Cut the outline of the bridge. Leave a little extra all the way around for safety. Follow your bridge foot outlines as closely as possible in this step and the next.


6. Reduce the bridge thickness as desired. This bridge will work best at about 5/16" thickness at the feet, but 1/4" will also work fine. You can leave the top as thick as 1/4". It is good to start thick and thin the bridge later if you want.


7. Fine-shape the bridge using files and sandpaper. (A belt sander and a Dremel tool can help a lot here, but are not essential.) Clean up the drill holes and the center saw cut using small round and flat files. Now you are to the stage of the scan below. Mark one side of the bridge in pencil as the "T" or treble side, or make some other mark so that you can tell which end is which.






8. Fit the feet to the top. This can be done with sandpaper on the top (Frank Ford's method at frets.com is useful), or for those with less experience, just get the mandolin, the bridge, and a small file close to a bright light, and start to work. This file method is slow but safe, and has less risk of scratching the mandolin finish.

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Here's how I fit a bridge, myself:

I use the sandpaper method. To protect the mandolin finish, I usually cut a piece of medium sandpaper about 1" x 7", and then cut a piece of heavy paper about 1" bigger each way. I attach the sandpaper, centered, onto the heavy paper with spray adhesive, Elmer's, or even a gluestick. Now the sandpaper ends and edges (potentially scratchy) will be physically isolated from the top.

I loosen the mandolin strings enough to leave a slight pressure on the top of the bridge. I take the old bridge off, then lay that two-layer paper/sandpaper thing down on the mandolin across the centers of the f-holes, then tape the ends of the paper onto the mandolin with masking tape extending over the binding and part way down the sides.

The strings keep pressure on top of the new bridge as I move it from side to side on the sandpaper. This seems to help a lot, both in sanding both feet the same way at the same time, and in keeping the bridge standing at the right angle. I use sanding strokes about 1/2" long, and the string pressure regulates it to about this far, anyway-- this seems to work fine as far as getting a good fit goes. I usually sand from the bass side for a while, then turn the mandolin around and sand from the treble side.

I take the bridge off every hundred sanding strokes or so and check it at a sharp angle to a bright light bulb to see how the fit is doing. Since my preliminary foot shaping is with a belt sander, the part of each bridge foot which now fits the mandolin top is much smoother-- it's easy to see. Sometimes if I was lucky with the belt sander to begin with, a bridge will surprise me and fit after only 200 or 300 strokes. Other times I can spend 15 or 20 minutes or more on this step.

Some bridges are really recalcitrant and never really look like they come to a great fit, but sometimes these are among the best-sounding bridges. All that goes to show that there's a lot yet to be discovered about mandolin bridges!

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9. If you want to preserve the same string-height as before, mark the top of the new bridge from the old bridge. Leave an extra 1/32" or more for now-- you can always take it down later. Cut or sand the bridge top down to the line. Mark the string slots in pencil on the bridge top, using your old bridge as a guide. Make sure the slots are centered not only on the bridge top, but also above the bridge cutouts.

(Click here for more details and suggestions about setting the bridge height.)


10. Make narrow, sharp file cuts on the pencil marks. Then enlarge the string slots slightly to fit each string, making sure that the slot bottoms are smooth and not in a "V" which will bind the strings. Slant the string slots a little downwards from front to back.

Now compensate the bridge with a small triangular or flat file.

I compensate most bridges very simply, leaving the E and D strings all the way forward and cutting the A and G strings about 3/32" back. You can also cut the D strings back from 1/32" to 1/16" if needed. Up-the-neck intonation should be excellent. Here's how some quick compensation cuts looked (this is a winged bridge):








...and now the bridge is ready for its first trial! You might plan on making not just one, but a few different bridges, in order to discover just what's best for your own mandolin. If your bridges are like mine, the workmanship on each one will be better and better.



Now for a few guidelines and observations:


Your first bridge may take a few hours to make, but after that it will go faster. If you have a band or scroll saw and a belt sander, the work can go really quickly.

It really is easier if you make the cutouts first, while you are working with a large, rectangular piece of wood which is easier to hold or clamp in a vise.

The oval cutouts in my earlier bridges took a lot longer to make than these simple ones, which are based on just round drill holes and short saw cuts. My first bridges took me four hours or so to make, and much of the time savings is in the change to round cutouts. The rest of my time savings came from learning just what has to be done, and in re-learning to use the tools.



Some frequently-asked questions are answered here.

To drop me a line with questions, click here.

Red Henry.






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