Tune-O-Matic replacement bridges' radius

[Aymara]

Hi everybody,

 

I have the Epi Les Paul Tribute 1960 and have two problems with the stock Tune-O-Matic bridge:

 

1. The radius of the bridge isn't the same as the fingerboard radius,

2. the wire over the screws started to rattle/buzz.

 

So I decided to replace the bridge with a better one.

 

Ok, this topic has been discussed several times and we know, that there are metric replacement bridges available, that fit without modifications to the guitar, like the Gotoh, Tonepros or Faber. A tech told me, that a Düsenberg bridge will also fit and is of high quality.

 

BUT ... what I never saw discussed is the radius of replacement bridges.

 

I saw, that the Gotoh has a 12" radius, but I didn't find radius specs about the other ones.

 

The problem is, the LP Tribute has a 14" fingerboard radius, so the bridge should have the same radius, right?

 

Ok, the Schaller roller bridge has a 14" radius, but it doesn't fit without modifications to the guitar's body, as far as I know. Because I don't want to loose my warranty, I'm not willing to do permanent modifications.

 

So, how do I adjust the radius of these bridges ... do I need to call a tech to file down the saddles to get from 12" to 14" radius?

[animalfarm]

Stewmac site:

http://www.stewmac.com/freeinfo/Repair_tools,_specialized/i-4557.html

 

Tune-o-Matic Wikipedia:

http://en.wikipedia.org/wiki/Tune-o-matic

 

EXCERPT from STEWART MACDONALD SITE:

 

"...most Tune-o-matics have a 12" radius, and this is often overlooked when setting up

Tune-o-matic bridges. Use Radius Gauges to determine the fingerboard radius, and match

it when shaping and slotting your saddles.

Often the string slots need to be off-center in order to get the proper radius.

 

I've never needed to change the Radius on any T-O-M bridge, so you are in "uncharted waters"

regarding any input I can provide. Based on StewMac site, it CAN be done....

[Aymara]

Thanks AF!

 

Often the string slots need to be off-center in order to get the proper radius.

I think, that's the wrong way, because the strings should be lined up to the screws in the humbuckers.

 

So I bet the saddles should be lowered instead, which would be a real hassle with metal saddles. Aren't there graphit saddles available ... I have a vague remembrance.

 

... so you are in "uncharted waters" ...

 

I feared, this would come ;)

 

Ok, so I'll need a good tech.

 

Or does anybody know a good 14" bridge, that fits?

[Whitmore Willy]

I might be way off base here but I just tried this and maybe you should do the same.

 

I taped a piece of string to my counter top. Measured to the string from the edge of the counter .

Set the center of a piece of paper the same distance off the edge of the counter and taped it 14" from the pivot point of the sting to the center of the paper.

Use a rule to make several accurate radius marks across the paper at 14".

Wrap the string around a sharp pencil until the point rests on my center mark. Now play connect the dots.

OK...you now have a 14" radius.

 

Untape the paper and move it to 12" keeping the center point the same distance from the edge of the counter.

Repeat process. You will end up with a 12" radius drawn over the top of the 14" radius.

 

Now take about 2" of those radius (About the distance from E string to E string on a guitar)

Now you tell me how much difference there is between a 12" and 14" radius over 2".

Personally, I don't think I could slot the saddles that accurately.

 

Now I'm not saying that I would use a 12" radius sanding block to do a fret level on a 14" radius neck.

You would be sanding the outsides of the frets before hitting the centers....But where saddles are concerned..

How much difference is there?

 

Also tell me what I would do if I had a compound radius neck with a 12" radius at the nut changing to a 14" radius

above the 12th or 14th fret.

 

Not trying to be a wise guy here but....I'm just not sure it's going to make that much difference.

 

Willy

[Aymara]

Not trying to be a wise guy here but....I'm just not sure it's going to make that much difference.

 

Interesting, Willy ... I'll check that out. Regarding the difference ... you might remember, that I visited a tech, because of buzzing problems. He found out, that a few frets aren't leveled and the bridge's radius doesn't fit the radius of the fingerboard.

 

He recommended loosening the truss rod completely and wait, til the neck settles ... it was too straight. Now the neck develops relief ... the open D string buzz is gone already, so I think a new nut isn't needed.

 

I'll wait a bit longer ... it's about a week now ... and then get a new bridge and let the tech take care about the frets and maybe bridge radius too. I'm curious, what he will say about the radius.

 

I'll keep you updated.

[AlanH]

Are you sure the fretboard radius is 14", Chris?

 

I thought most Gibsons and Epis came with a 12" radius, especially LPs. 14" is more in to 'Superstrat' territory e.g. my Kramer has a 14" radius and my Charvel has a 12-16" compound radius. Both fretboards feel distinctly flatter than those on my two LPs.

 

You can buy special metal templates to measure fretboard radii and, if you buy the Dan Erlewine How to make your guitar play great book it comes with a free set of pop out 'plasticard' templates. You could also make your own out of strong card.

 

To measure fretboard radius accurately you need to have the strings off/loosened.

 

Alan

[vomer]

Aymara, your tech will probably increase the depth of the slots in your saddles. I did it to my Sheraton which has the same combination of radii as your LP. As Willy says, it's not a big difference, but it does make a difference. If I recall, I think I mostly just lowered the D and the G on mine. It's a common situation and your tech should handle it easily. Don't worry about trying to find a 14" bridge.

 

The string retaining wire can be bent to curve around each screw to stop them buzzing.

 

Given both of these points, you don't really need to buy a new bridge, unless you really want to spend money on something of much higher quality.

[Hungrycat]

It's design flaw inherent with Gibson instruments. There are many flaws in Gibson designs. They won't fix them because then it would look like Gibson is admitting that they were wrong in the first place.

[Aymara]

Are you sure the fretboard radius is 14", Chris?

 

I was also sceptical about this, especially because the D and G strings were the ones, that buzzed the most. But the reasons were not enough neck relief (solved now) and the 4th fret being higher that it's neighbours.

 

The 14" radius is written in the specs on Gibson's website.

 

They won't fix them because then it would look like Gibson is admitting that they were wrong in the first place.

 

Who knows, why they don't fix it ... maybe costs play a role too ... fact is, it's one of the reasons, they loose more and more potential customers. The competitors don't sleep, as we say in Germany ;)

[james_edward]

After a quick calculation, the difference between a 12” radius and a 14” radius is that the smaller radius sits approximately .005” higher at the crown of the neck.

 

As there is no string in the center of the neck, this means the D & G strings would need to be lowered even less than .005", while the A & B strings effectively are fine where they are.

[Aymara]

Thanks James!

 

After a quick calculation, the difference between a 12" radius and a 14" radius is that the smaller radius sits approximately .005" higher at the crown of the neck.

 

That would be 0,125 mm in the center ... it seems a 12" radius Gotoh should work fine.

[AlanH]

 

The 14" radius is written in the specs on Gibson's website.

 

 

I didn't know that. Is the 14" radius just on the new upgraded models?

 

I thought that the standard and standard plus models had 12" fretboards but there is no detailed spec for these on either the Gibson or the Epi websites.

 

I'll measure mine next time I have the strings off.

 

Alan

[Aymara]

Is the 14" radius just on the new upgraded models?

 

Only a few newer models seem to have the 14" radius ... maybe only the 60ies orientated models? I don't know.

 

The 50th Anniversary 1960 Les Paul also has 14" fingerboard radius, the Joe Bonamassa Les Paul has 12".

[Gordy01]

As a few of the guys have already mentioned, your 12 in bridge will fit your guitar. The bridge saddles can be filed with a nut file, just like filing the nut. That is actually how a tech lowers any high strings at the bridge anyway.

To take .005 off of any one of the saddles is a quick and easy job.

Someone else mentioned a set of radius guages. I bought a set of "Understring" guages that work fine to measure the neck as well. Bought them at stewmac, fairly inexpensive as I remember.

[Aymara]

your 12 in bridge will fit your guitar.

 

Good to know.

 

But I think replacement bridges were discussed too often the last weeks in several forums ... the Gotoh is sold out at Thomann.

 

Gotta visit my tech again. He said the Düsenberg bridge will fit and is of high quality for a similar price as the Gotoh. Because he's Düsenberg dealer, I think he can get it fast. The only current poblem are the outdoor temperatures ... it's snowing :(