Acoustic Guitar Construction

Cumpianos book has a pretty basic bridge and a full size template plan. I will be making one soon.

Ha, the saddle on that twelve string must have been epic work! Frets link is great just what I was after, ordered the teeter book too after reading ken's review.

Do pinless bridges not usually have bridge plates? I have a steel string with a classical bridge that has one.

mike-p wrote:Do pinless bridges not usually have bridge plates?

Definitely need a bridge plate. I have both Teeter books, you'll love them.

Mike-p - it was a lot of work, but worth it. The standard compensation is especially ineffective on the "octave" strings of the upper four courses on a 12 string. The compensation works, to the extent it works at all, only for the wound string.

Tim, why is a bridge plate necessary on a pinless bridge? On the Harmony 1260 there is a strip of spruce running horizontally under its pinless bridge that does not couple with the sides, but the 1260 is ladder braced and the bridge is set between two of them. On an X-braced instrument, presumably the ends of the pinless bridge would extend to the lower legs of the X, forming the usual triangle, which is intrinsically strong.

This is a question, not an objection.

Many old timey and modern Classic guitars and hybrids all nylon stringed, have a reinforcement under the bridge. I believe the thinking is that plate will help prevent the bridge from rotating over time -- as well as crack prevention. So if this is the case -- perhaps a plate makes even more sense with the higher tension steel strings?

Since the stiffness of the X-brace varies as the cube of its height, a slight increase in height there seems like it would go further in preventing rotation than a thin piece of maple spread all around underneath its surface. But certainly, the plate adds some strength, especially if it is let into the legs of the Xes. And I have noticed that Greg Smallman increases the use of CF under the bridge, despite the incredible overall intrinsic strength of his lattice I-beam design.

John Monteleone makes the point that it is "10 times easier" to spread string energy along the length of top grain than across grain, so I can see the point of having the spruce underneath the bridge in a ladder braced top where the bridge is not attached to any brace that crosses grain. But X-bracing kind of takes care of spreading energy across the grain by virtue of its "all-overness", just as does lattice bracing.

It is not unthinkable to make an instrument with a pinless bridge without a plate and waiting to see how it does, while retaining the option of adding the plate later. May not make much difference either way. Certainly, if one leaves off the plate on a pinned bridge, the ball ends will soon chew up the soft top, and that would make a difference.

There's no need to experiment -- some of the msot prized guitars around today are from "George Lowden" and happen to be made with pinless bridges -- I won't spoil the surprise -- but I'd check out what he does.