Acoustic bass...string pins keep popping out!

[Irishbass]

I was given an Ibanez acoustic bass guitar by our singer who owns it but never plays it, to try on some unplugged gigs... some time ago I had a Rob Allen MB-2 which I sold, but had a spare set of la Bella tape wounds lying around. I think they will be nice on this little bass but I cant get the pins to hold them on the bridge, when I put any pressure on they just keep popping out! So I figure it must be these strings it doesnt like? Any tips on how to get the pins to hold the strings in? I tried stuffing bits of cardboard down to tighten up the gap but still no good...

[202dy]

There is a common misconception about bridge pins. That is that they are meant to hold the strings in the bridge. They are not. Something under tension cannot be anchored with something that is mobile.

The ball end of the string should come to rest on the bridge plate. The bridge plate is a piece of wood, usually spruce, that is glued under the top directly below the bridge. It reinforces the top to minimize the hump caused by the bridge being in rotation from the pull of the strings. It also serves as a mounting surface for the ball end of the string.

Put the string through the hole in the bridge. Place your hand through the sound hole. Reach down and find the ball end. bend it slightly while installing the bridge pin, making sure that it is contact with the plate rather than the bottom of the pin. Install the end of the string and tune. Repeat with the other strings.

Some folks feel that doing this correctly will increase the tone and volume of the guitar.

On a side note, incorrectly installing the strings so that the ball end is at the bottom of the pin is the major reason for bridges splitting through the pin holes. A bridge pin is a conical wedge. Repeated pushing and hammering them into place in an attempt to use friction to hold the end of the string results in splitting the bridge as neatly as using a wedge when splitting logs.

[walterw]

well, a spruce bridge plate would last about a month (they should be maple or rosewood), but otherwise +1 on all counts.

too many budget acoustic basses have bridgepins and bridge holes with too narrow a slot for the strings, so they jam up in there, not allowing the ball to rest against the edge of the hole like it's supposed to.

[dannylectro]

One of the many reasons I love my Breedlove...

[T-Bird]

Hi.

Since the Kodak ad department said it best back in the day:

Originally Posted by dannylectro

One of the many reasons I love my Breedlove...

Up until the bridge separates from he soundboard or splits in two.

Regards
Sam

[202dy]

Originally Posted by walterw

well, a spruce bridge plate would last about a month (they should be maple or rosewood), but otherwise +1 on all counts.

too many budget acoustic basses have bridgepins and bridge holes with too narrow a slot for the strings, so they jam up in there, not allowing the ball to rest against the edge of the hole like it's supposed to.

Absolutely 100% correct. Thank you.

Maple, typically, and sometimes rosewood are the choices. Both work well.

My apologies. Must be getting axheimer's disease.

[Irishbass]

great info guys.. and why TB is such a useful source... many thanks!! Dave

[bassbenj]

Originally Posted by Irishbass

great info guys.. and why TB is such a useful source... many thanks!! Dave

You said it you lucky dog! I had to figure all this out myself the HARD way! Like everyone else I had the misconception that it was the friction of the end pin that held the strings in. And after a huge hassle trying to somehow increase the friction of the pins, it finally dawned on me how these things work!

All the people reading this are now lucky enough that they don't have to go through the stupidities that I did. Let's hear it for TB!

[walterw]

Originally Posted by T-Bird

Hi.

Since the Kodak ad department said it best back in the day:

perfect!

Originally Posted by T-Bird

Up until the bridge separates from the soundboard or splits in two.

yeah, pinless bridges always bugged me. rather than relying on the mechanical strength of the bridgeplate to take the string tension, the strings pull sideways right on the bridge, so the whole thing is only held on by glue.

plus, you can't pop the strings out without undoing them from the keys. makes these guitars harder to work on.

[202dy]

Originally Posted by walterw

perfect!

yeah, pinless bridges always bugged me. rather than relying on the mechanical strength of the bridgeplate to take the string tension, the strings pull sideways right on the bridge, so the whole thing is only held on by glue.

plus, you can't pop the strings out without undoing them from the keys. makes these guitars harder to work on.

Yes, they are a bit more fussy to work on. However, the theory is that since the string pull is straight(er) than on a pin bridge that there is less rotational force on the bridge. The advantage touted is that the top tends to stay flatter.

Ovation uses this style of bridge. Many older Ovation tops would hump. The factory claimed this was due to the use of fan bracing like a classical guitar rather than the X braces used on steel string flat tops.

One thing is certain. When the top lifts on a pin bridge, there is a hump behind and a dip in front. Pin-less bridge tend to dome the top.

Either way, a pin bridge is easier to relocate when re-gluing.

[scotch]

Originally Posted by 202dy

... Something under tension cannot be anchored with something that is mobile...

Well, violins, violas & cellos don't support this claim!



Friction still working after 100's of years!

[scotch]

Originally Posted by T-Bird

Hi.

Since the Kodak ad department said it best back in the day:








Up until the bridge separates from he soundboard or splits in two.

Regards
Sam

That illustrates it perfectly!

Regarding pinless, straight pull acoustic bridges - I agree that it is inconvenient for string changing and repair/setup work. However, I've played 15-year old Lowden's and some older Taylors with pinless that still play perfectly, have no hump and haven't cracked at all. Seems to be a perfectly sound design, although not my preferred approach.

[202dy]

Originally Posted by scotch

Well, violins, violas & cellos don't support this claim!

Friction still working after 100's of years!

Many differences here. The peg box and the peg in the violin family are matching tapers. That is rarely true in the guitar family of instruments. It is almost unknown on acoustic bass guitars. The violin peg is resisting rotation of the string. The guitar pin is attempting (when incorrectly installed) the pull of the string on the bottom of the wedge shape, opposite the direction the pin is inserted. Violin users quite often use peg dope on their pegs to increase resistance. Peg dope is basically weak adhesive.

Acoustic guitar pins are designed to lock the string in place. When correctly installed, the pins can be removed and the guitar will still function correctly.

In the interest of keeping this debate friendly a restatement is in order: Something under tension cannot be held in place by something that is mobile in the direction of insertion.

[walterw]

there you go. the string is not pulling the bridge pin directly out of the bridge, nor is it pulling the violin peg out of the pegbox.