Pinless bridges

[ZekeM]

Ok so I been thinking about Pinless bridges. I hate fooling with bridge pins and it seems like it could make restringing a much more enjoyable process. So what's some opinions? Also some questions I have.

When using a Pinless bridge is it still necessary to have a bridge plate glued on the inside of the soundboard? You no longer have the strings pulling up against it so it may not be necessary?

Also I could foresee a problem with the balls on the ends of the strings pulling into the wood at the back of the bridge. Is this a problem? What if you pressed metal ferrules like used on some electric guitars? Would those be a tone killer?

Thanks for all the input everyone.

[runamuck]

The only disadvantage I'm aware of is that one needs to be more careful
stringing up so as not to scratch the top.

Jim McCarthy

[redir]

I've never built a steel string guitar this way but many classical guitars and some luthiers still put a Popsicle bridge patch under the bridge some don't. I used to but have since stopped doing so as I've changed my design philosophy about it. So basically my guess is it's ok with and it's ok without but wonder what other steel string builders think. Also I wouldn't worry about the ball ends on the bridge if you are using ebony or rosewood.

[ZekeM]

Thanks for the info so far. I was worried that the balls on the strings could cause wear over time and thought the metal ferrules could be a good thing to prevent it. It's my guess that a patch may not be necessary though I'd love to hear from someone more experienced

[Ken Donnell]

A pinless bridge works just great for steel string. It changes the dynamics of how the strings pull against the soundboard, so that the bridge is rocked forward more than for a pin bridge. so, you may want to make certain there is sufficient reinforcement from the internal braces between the bridge and soundhole. The only disadvantage I have experienced from pinless bridges is that they are more prone to having the bridge come unglued in a spectacular fashion since there are no pins to hold the bridge to the soundboard.

[John Arnold]

It changes the dynamics of how the strings pull against the soundboard, so that the bridge is rocked forward more than for a pin bridge.

If the height of the strings above the top is the same, the torque is the same.
I would be reluctant to build one without a bridgeplate, because the top would be more flexible. If the top is able to flex more, the bridge could peel off more easily.
My main complaint with pinless bridges is that it makes it harder to remove the strings without cutting them off. I have a habit of saving old strings, and pulling the coiled end through the hole in the bridge is tedious.
Also, it makes it harder to do saddle adjustments.

[ZekeM]

John and ken thanks for the info. I'm contemplating doing a pinless bridge now. I'm thinking That instead of the traditional bridge plate maybe just a brace to stiffen the area under the bridge will suffice. I'll have to do some experimenting before proceeding. I know some guitars have pinless bridges that are bolted to the top so they won't be as likely to lift but that has got to kill the tone so I'll just hope the glue holds.

[John Arnold]

Small screws like Gibson uses (#4) are not the tone killer you may think.

[ZekeM]

#4 is tiny. I guess those couldn't effect tone much.

[brad4d8]

There are some who claim that the upward pull of the strings with a pin bridge imparts more energy to the top. There is, or maybe used to be, somebody who took old Harmony Sovereigns and replaced their pinless bridges with a pin bridge and claimed that it improved the sound. Don't know personally.
Brad

[murrmac123]

Originally Posted by Ken Donnell

A pinless bridge works just great for steel string. It changes the dynamics of how the strings pull against the soundboard, so that the bridge is rocked forward more than for a pin bridge.

Originally Posted by John Arnold

If the height of the strings above the top is the same, the torque is the same.

It is by no means universally accepted that the torque is the same (ie that the saddle breakover angle and the string height above the soundboard are the sole factors determining the torque exerted on the soundboard)

Far from the bridge being rocked more in a pinless configuration, I would contend that the reverse is actually true, and that you have to consider the anchor point of the ball end when calculating the leverage exerted on the soundboard.

If the ball end is located underneath the bridge, there is more torque being exerted than if the ball end is above the soundboard.

[John Arnold]

It is by no means universally accepted that the torque is the same (ie that the saddle breakover angle and the string height above the soundboard are the sole factors determining the torque exerted on the soundboard)

I think you are confusing break angle with torque on the top. More break angle means more downpressure on the saddle, and more pressure on the bridgeplate from the string balls. But the torque on the top is only a function of the string height and string tension. That is Statics 101.
What more break angle does do is increase the energy transfer from the strings to the saddle, and to the bridge.
In other words, any improvement in the sound when converting to a pin bridge is due to an increased break angle.
'

[arie]

well, however it is sliced and diced the bottom line is that you are establishing a basic lever.

i wouldn't bother with metal ferrules because you will just add weight to the bridge. what i would be careful about is preventing the bridge from cracking apart (like many ovation bridges) no thin walls, no sharp edges, no weak areas.
choose your wood carefully and keep your hole distances reasonable.

i would also think about using a bridge plate because they do much more then keep string balls from plowing through the top. the classical builders have a bit more leeway in this area because string tension is about a hundred pounds less on the top vs steel string so they can choose to use one or not.

[ZekeM]

Ok arie thanks for the excellent advise as always I hadn't even thought of the bridge cracking in half. I'll have to think a little more about that

[Ken Donnell]

Originally Posted by murrmac123

It is by no means universally accepted that the torque is the same (ie that the saddle breakover angle and the string height above the soundboard are the sole factors determining the torque exerted on the soundboard)

Far from the bridge being rocked more in a pinless configuration, I would contend that the reverse is actually true, and that you have to consider the anchor point of the ball end when calculating the leverage exerted on the soundboard.

If the ball end is located underneath the bridge, there is more torque being exerted than if the ball end is above the soundboard.

Afraid we will have to agree to disagree on this. it's all theory, but it is great to have such a lively discussion with multiple points of view. Thanks to everyone in this thread.