Author Topic: Bridge Problem (Read 790 times)

terryc · « **Reply #15 on:** October 05, 2009, 02:40:01 AM »

Brass screws are soft but it still would take a lot of tension to do this and if you notice all three have failed..this is strange as if all three must have been pulled at the same tension..each string is at a different tension due to their guage.
The string retainer looks odd..a thin brass plate with a thick piece of wood??? surely Alembic would not build a item like this as the wood would wear quicker than the plate where the ball ends of the string are located.
You could drill them out yourself but the bass would have to be firmley anchored in a jig and a drill on a fixed vertical stand would have to be used utilising a hardened bit and turned very slowly to gently drill out the remaining brass remains.
This is an unusual event, if you want help from Mica then supply her with all the relative info(serial number and a pic if possible)
Good luck in the repair

adriaan · « **Reply #16 on:** October 05, 2009, 03:26:37 AM »

Terry - the brass/wood combo for the tailpiece is actually how Alembic did it for the first couple of years. Nowadays it's a standard feature on the Brown Bass.

David Houck · « **Reply #17 on:** October 05, 2009, 06:16:46 AM »

As Adriaan suggested, a brass tailpiece with a wood shim, is not unheard of. A relatively thick piece of Ebony can often be used for a nice visual effect, setting off the tailpiece from the body in a manner similar to accent lams setting of a top body wood from the main body.

georgie_boy · « **Reply #18 on:** October 05, 2009, 06:51:00 AM »

As David said.........The wood is how it was done back then!
I have the same tailpiece, and it's wood on the underside. They didn't have the facilities at the time to machine the solid brass.
This looks to be a real bad problem here, and I would say that it's nothing to do with heating a house!
I live in Scotland, and during the Summer, my windows are slightly open...no probs. In Winter, the windows are closed, and the central heating is on.
Result??
NOTHING!
Seems that, no matter what I do at home.or even live, she doesn't move at all. Great for me, but not so good in this case!!
I'm sure, that a competent luthier could fix this no problem.

George

terryc · « **Reply #19 on:** October 05, 2009, 06:52:44 AM »

Well you learn something everyday..personally I prefer the solid metal approach, the BadAss II was a great improvement on my old P bass.
Adriaan/Dave..what did you think about my comments on the tri fracture of the screws?? as I said they would all have to have equal tension to cause that..it is very bizarre how it has happened.

keith_h · « **Reply #20 on:** October 05, 2009, 07:39:07 AM »

Terry,
You are talking apples and oranges here. The Fender style bridge also contains the tail piece. On the Alembic the tail piece is not part of the bridge so it has minimal if any effect on the tone or sustain.

Keith

David Houck · « **Reply #21 on:** October 05, 2009, 07:47:28 AM »

I really don't know; I suppose the screws could have fractured one at a time over time, with the last holding everything together until it too let go.

FC Bass · « **Reply #22 on:** October 05, 2009, 08:19:36 AM »

I think (I?m almost sure) the solid Brass tailpiece has a huge impact on the sustain of Alembics, but that's a bit of topic I guess... :-)

Ugly sight... :-(
Clearly moving wood/metal (brass) fatigue case if you would ask me.
I think everyone with Brass screws should follow Mica's advice as stated in 811952's first post in this topic.
Whether or not he recalls it right, it makes a lot sense to me and I think it will prevent more birds from flying out...

Hope you get her well again soon.

(Message edited by fc_spoiler on October 05, 2009)

keith_h · « **Reply #23 on:** October 05, 2009, 10:02:15 AM »

The bridge is where the largest effect on sustain and tone comes from. Keep in mind the vibration of the string is between the bridge and nut not the tailpiece and nut. The whole idea behind the bridge block and massive bridges is to keep the energy in the string and not let leak outside of the area between the saddles and nut.

Keith

811952 · « **Reply #24 on:** October 05, 2009, 11:21:10 AM »

Once the first screw lets-go, there is increased tension on the remaining two. Once the second screw lets go... it's going to be a chain-reaction of failure (not unlike many things I've been involved with, but I digress..).

John

terryc · « **Reply #25 on:** October 05, 2009, 11:42:14 AM »

keith h..I wasn't talking about the sustain factor, merely the durability of the string retainer, if the ball ends were digging into the wood than along would wear the retainer out.
Sorry for the confusion.
811952..I agree that as one goes that the other two would go due to increased strain..I am going to try something like this in the garage later this week to see if a brass screw is really that weak..but I ain't using my bass!!!

toma_hawk01 · « **Reply #26 on:** October 05, 2009, 12:06:50 PM »

I would Gorilla glue it back.

Tap all the ends, and around base, and clamp it down.

How can anyone go into the wood, and extract the broken screws, without adding more damage?

Also, if you try to make an attempt to remove the broken pieces, you are definitely going to have to make the holes (which are trapping the screws) larger than the original hole.

I would glue it, and if that failed, then I would perform major micro surgery.

Secondly, As how this happened?

Heat didn't cause this...

I believe it is highly unlikely that all three screws broken at the same time. I believe they were broken from somebody tightening them too tight, or if they were on too tight, somebody tried to remove and possibly broken just enough to go undetected!

From the closer looks from the breaks, they look to be at different areas. Also, I see no corrosion. The breakage looks sharp and jagged at the ends, and I don't see the broken inner core giving a new sheen, as a fresh break. Those breaks look old.

I would like to take look at the heads of the screws. I would bet, machine was used by someone years ago.

I suspect it was an hidden accident, waiting to happen.

PS...

Oh, wait a minute.... do I see silicon around the screws and on the body of the bass and screws?

Looks like it, maybe this bass had the problem before you knew about it... Hmmmm mmmmm

Good luck.

(Message edited by toma_hawk01 on October 05, 2009)

toma_hawk01 · « **Reply #27 on:** October 05, 2009, 12:53:08 PM »

Warning!

Consider the risks when removing brass screws in general.

keith_h · « **Reply #28 on:** October 05, 2009, 02:30:33 PM »

Terry,
I just assumed you were talking about the effects on sound as opposed to the general construction.

I own a Brown bass which uses an ebony shim under the brass tailpiece. There is very little wear on the wood as all of the stress is on the brass. I cannot speak for the earlier basses but on my BB the brass is thicker at the front and the ebony is thicker at the back.

Keith

toma_hawk01 · « **Reply #29 on:** October 05, 2009, 02:55:01 PM »

Here's another solution...

Fill the holes with wood a wood filler, let it dry, and hand screw (with a screw driver) the screws back into the wood filled holes. With the additional compacted wood dust should hold the threads of the screws. I would still tap the tail piece with glue just for assurance.