Double Bass Tailpiece exploded, need to replace

[stanford ekholm]

For a focused strong sound, the tailgut shouldn't be too long. Read a scientific report done on the cello tailgut length were this was confirmed, think it was about 1/2" optimal. Guess on a bass it shouldn't exceed 1". Put it in this position and measure after length to 1/6 the string length and you've got the proper length of the tailpiece.This is how, for instance, Radelet make his tailpieces (15").Tailgut length overrides after length by far the impact on the focus/resonance scale.

 

[stanford ekholm]

bear in mind that a drilled-through tp will act like a raised saddle, the distant to the plate will increase by perhaps a centimer, creating a more obtuse angle over the bridge, and consequently less pressure on the plate. Which could prove beneficial or bad depending on the string tension.

 

[robobass]

bear in mind that a drilled-through tp will act like a raised saddle, the distant to the plate will increase by perhaps a centimer, creating a more obtuse angle over the bridge, and consequently less pressure on the plate. Which could prove beneficial or bad depending on the string tension.

This idea has been discussed ad nauseam here in the past. It is simply not the case. While the position of the tailpiece changes, the actual tension is in no way affected.

 

[stanford ekholm]

This idea has been discussed ad nauseam here in the past. It is simply not the case. While the position of the tailpiece changes, the actual tension is in no way affected.

you didn’t quite catch my point, where i’m i saying the string tension changes? Read again! i’m talking about the pressure on the plate, which is determent by your actual string tension (brand of strings) and the string angle over the bridge.

 

[DoubleMIDI]

What is a drilled-trough tailpiece?

Nothing replaces a raised saddle.

I know tailpieces with a large rectangular hole at the lower end which hook into a raised wooden post from the end block.
If that post is long, the tailpiece starts higher than one with a tailgut over a standard saddle height. But no one would change one for the other. That would need a substantial permanent change of the instrument.

As long as the tailpiece can move freely, it will adjust its position so that the shortest line from saddle to bridge top is reached. The underlength and tailgut fit that line.

The only thing that can change the string pressure to the bridge is to change the position where the string leaves the tailpiece if mixed (not if all go from below instead of the above, the tailpiece position simply changes in that case). But the total pressure is the same, just differently distributed over the strings.

 

[stanford ekholm]

What is a drilled-trough tailpiece?

Nothing replaces a raised saddle.

I know tailpieces with a large rectangular hole at the lower end which hook into a raised wooden post from the end block.
If that post is long, the tailpiece starts higher than one with a tailgut over a standard saddle height. But no one would change one for the other. That would need a substantial permanent change of the instrument.

As long as the tailpiece can move freely, it will adjust its position so that the shortest line from saddle to bridge top is reached. The underlength and tailgut fit that line.

The only thing that can change the string pressure to the bridge is to change the position where the string leaves the tailpiece if mixed (not if all go from below instead of the above, the tailpiece position simply changes in that case). But the total pressure is the same, just differently distributed over the strings.

Think you're right, thanks for the input! (wish I could delete my entry, is misleading)

 

[1st Bass]

Gracious concession. Well done!

 

[robobass]

No worries. Lot's of people have held this view, and it has taken no small effort to convince them otherwise

 

[stanford ekholm]

actually, the idea that you could replace a raised saddle with a designed tailpiece was something I read on a pedigree (bass)luthiers website. Thinking a bit harder than usual on the physics, as doublemidi clearly has done, this seems only to work in a cartoon (think Mickey Mouse has this setup on his bass, you know, the clip were he solos in that Christmas song?).

 

[stanford ekholm]

the luthier mentioned above still has it on his site, what do you think of it?
Jeff Bollbach Luthier, Inc.: Luthier Rant

 

[TroyK]

Chris, I have one that I'm not using and am happy to send you. It's about 13 1/4" in total length. I can take other measurements if it helps.

I'm of the camp that this is a very precise and complicted equation and I'm not an expert in it, but it seems that where the tailpiece wire comes in would be an an important factor as would the difference between the string holes (technical terms) and the bar that the strings come over. I'm happy to take more measurements if you're interested.

I look at this thing now and again and ask myself "why am I holding onto this?" It got displaced when Jake built me a custom one. It's yours if you want it.

Having Jake make you one to your specs is not a bad idea either.

 

[DoubleMIDI]

the luthier mentioned above still has it on his site, what do you think of it?
Jeff Bollbach Luthier, Inc.: Luthier Rant

I contacted Jeff by mail and showed him a way to proof that the kind of tailpiece itself has no effect on the string angle at the bridge.
Maybe he jumps in here, I gave him a link.

 

[Chris Fitzgerald]

Thanks @TroyK . The tailpiece that broke is only 11” long. I think I’m going to have to make a trip to the Cellar and leave it with them. At this point, I may try a Krivo on it, and if I don’t like that, then maybe sell the bass. I have seen Rufus travel with a real removable neck bass for years, and though I don’t travel as much as he does, that option seems like the best in the long run.

 

[DoubleMIDI]

Chris, you can either glue the broken end to the tailpiece or round it up a bit for a nicer look.
The missing mass down there has only a very small influence on the sound. The influence of missing mass close to the underlengths would be much larger.

Then drill two holes through the tailpiece just above the broken part or through the broken part, a quarter width from the edges on each side. The underlength might get a bit longer because the tailwire might be a bit too short. But if you drill in the middle of the broken part it should be almost the same. I wouldn’t drill any lower than that for stability reasons.
You might want to drill diagonally from top to bottom to remove stress on the wood.
Start at the top close to the upper end of the broken part and towards the lower end of the tailpiece. I think a 45 degree angle would be fine. There is a bit more stress on the top end of the hole, but less total.
Filing down the broken surface to equal height at the holes on the underside avoids a slightly rotated tailpiece.

Then you need to open the tail wire loop to fiddle the tailwire from below the tailpiece to the top and back through the other one to the bottom. Then close the loop and fix it. Check the underlength before the final fix.

It’s a bit of work and might look a little bit strange, but you can use the bass again and can change to a different tailpiece later if you want.

 

[DoubleMIDI]

I contacted Jeff by mail and showed him a way to proof that the kind of tailpiece itself has no effect on the string angle at the bridge.
Maybe he jumps in here, I gave him a link.

Jeff answered that it was a misconception (“loud thinking” he said) but for various reasons he was (and is) not able to remove that part from his web page.

So no tailpiece can replace a raised saddle because it only changes position of itself if built or connected differently but cannot change the position of tailwire or underlength and therefor not the string angle over the bridge.

 

[stanford ekholm]

I, like Chris Fitzgerald, have a preference for a heavier tailpiece (250-300g), harmonics produced by plucking/bowing nearer the bridge. Makes for a focused, projective and beefy sound. Just wondering if a similar result could be achieved with a light tp by setting the tailgut short and placing the soundpost closer to the bridge?

The weight of the tp has a great impact on the sound, wouldn't it be awesome to have it adjustable? Have an idea of using a couple of the string holes to attach a plate (or several) behind the tp, what you think?

 

[DoubleMIDI]

I, like Chris Fitzgerald, have a preference for a heavier tailpiece (250-300g), harmonics produced by plucking/bowing nearer the bridge. Makes for a focused, projective and beefy sound. Just wondering if a similar result could be achieved with a light tp by setting the tailgut short and placing the soundpost closer to the bridge?

The weight of the tp has a great impact on the sound, wouldn't it be awesome to have it adjustable? Have an idea of using a couple of the string holes to attach a plate (or several) behind the tp, what you think?

That should work nicely for experiments.
But keep in mind that if you put a weight at the string holder side it has more impact than putting it at the other side of the tailpiece. So you cannot just get a tailpiece that is the same weight than your experimental one and expect to work the same. It typically needs to be a bit heavier.

 

[DoubleMIDI]

Thinking about the diagonal holes again you also can drill the holes normally but round the holes on the underside a bit to reduce stress on wood and tailwire (not that much important with your steel wire but can be with a tailgut).
This avoids a hard kink in the tailwire and a high pressure at the edge where the tailwire bends towards the saddle.

The diagonal bore saves you a bit if tailwire length, so feel free to bore any angle between 45 degree and straight through.

It is a good idea to avoid hard kinks anywhere like at the bridge (round the grooves towards fingerboard and tailpiece) and the pegbox side of the nut (I round them at least half of the groove length so that there is no kink at all but the string lifts slowly from the groove).
Not an issue with robust steel strings like Spiros, but can help to avoid breakage for synthetic and gut core strings.

 

[Chris Fitzgerald]

I’m thinking of a compromise and wanted to run it by the brain trust. I tend to stay pretty crazy busy and school is starting up again soon. On top of that, I don’t quite trust my skills or patience to do the glue/drill repair suggested here.

But I don’t think this needs to be a “full day trip to Cincy” kind of fix, either. There’s a local luthier here in town who works on all the school system string instruments and does a good job with that. He’s not a bass specialist per se, but his shop does a good job with seam repairs and the like. I go to Cincy to have fingerboard and fine setup work done, but I bet this shop would do a far better job of making this tailpiece work than I would, and their prices are reasonable.

Where I’m at with this bass: Obviously, it will only get played when I have to travel by plane, and usually only internationally when I know I can’t borrow a DB where I’m going. Plus, I haven’t found the sweet spot for amplifying it. I was thinking of trying a Krivo on it, and if I hate that, maybe just sell it and try to find a full size travel bass. I’m getting closer to retirement and not sure how much international travel is in my future, so the question may be getting more moot.

 

[Don Hergert]

Chris, does this require a Kolstein tailpiece for the time being? If not, your local luthier's shop may have a replacement tailpiece that would work, or could be made to work, as you order a new tailpiece for your model, to be shipped to you from Kolstein. Then you'd have a backup in case the new Kolstein tailpiece repeats the explosion of the original one.

I'd also be curious as to why the original tailpiece exploded in the first place. True, the mounting method and wood grain may have contributed to this problem, but is it possible that the strings might be too high tension for this tailpiece, and if so, for the DB itself? If this DB does turn out to be one you do want to keep, that answer might be important. I know in the smaller fretted instruments, many high-quality manufacturers specify only as high as "medium tension" strings.