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Just
a reminder: this is the bridge we don't want anymore:
Now we make the bridge that's better. Ah!
First I find a nice piece of rosewood that matches the fingerboard,
and I trace to outline
I cut the piece out on the bandsaw, true up the gluing face and the
long straight side,
The rough end is OK since it'll be gone shortly.
I fine-tune the bridgepin holes first, using dividers to ensure perfect spacing. They must be a precise distance from the back edge, and from the ends,
as well as from
Then I drill the holes with a brad-point bit on the drill press. 3/16" holes are just right. Then I lay out the slot for the saddle, making sure first that it is located just right.
Once the slot is laid out, I use a jig on the drill press to route that
slot. I use a 3/32" carbide
Here's a look at the simple but effective jig. I have made hundreds
of bridges with this jig.
Now I begin to refine the surfaces of the bridge, starting with the ends and the long curved edge. Using the bridgepin holes with 3/16" bolts through them as guides, I
check the ends first. Remember
Check all sides to make sure the edges all line up. Then proceed to refining the bridge's top surfaces. The bridge should be higher on the bass side:
I finish-sand the surface, and particularly the wings, by hand with
abrasive paper mounted to
OK, now the bridge is ready to put in place for a dry run of the glue-up. First though, I make a caul for the inside of the guitar, so I can clamp the entire bridge safely. I use the bridge as a guide for drilling the #1 and #6 holes in the caul.
The diagonal masking tape marks brace locations; the caul (this one's
scrap walnut)
Now I take off the diagonal tape and go for the final refinement of the gluing surface. While the bridge is temporarily but firmly affixed with 3/16" bolts
and wing nuts,
You only get one chance to do this right. No mistakes allowed.
The scored line will make the lacquer break like glass. Below is the business end of a mezzotint rocker. It's a tool art engravers
It's about 7/16" wide. Sometimes I use it like this:
The finishes just shatters and pops off, but it doesn't remove wood. I can now use the rocker upside down as a horizontal saw
I also use my violin knife, the large one, to clean the back surface. You essentially inlay the bridge into a precision hole in the finish. Again, no slack.
The top's spruce is now patched, dead flat, precisely cleaned to
Now I put a double-thick pad of cork on the bridge caul; remember, it
has
A dry run to make sure everything fits perfectly, then the real operation:
I run two bolts through to wing nuts inside on the other side of the
caul and make sure the bridge
This means taking off the tape, and completely washing the entire
After the glue has dried overnight, I leave the caul in and remove
the bolts and two of the
Do not drill bridge pin holes clear through the back! The caul prevents tear-out inside. It's usually slightly glued on after
the gluing procedure,
Now the bridge is ready for all the little setup procedures:
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