Harmonica Bridge

Harmonica Bridge

Postby TI4-1009 » Thu Nov 29, 2012 9:04 am

Found this over on the SG page-

Bridge problems

--------------------------------------------------------------------------------

74-ish SG Standard with harmonica bridge. Chrome is bubbled and it looks like cr@p, so I went looking for replacements.

Trouble is, these harmonica bridges seem to frequently get flipped around. They are not 100% symmetrical on each side and the saddles are sloped on one side, and 90 degrees on the other. Plus they tend to be grooved for whether it was the bass E or the high E, etc.

So here are my questions -

1) Should I care? I found out my other 74 SG seemed to have a flipped bridge and it's played like a champ for years.

2) If I should care, what is the "right" way for these bridges to be positioned?

3) If the saddles are grooved wrong, is it possible to disassemble these bridges and move the saddles to the right spot? I tried but failed.

I now have 3 harmonica bridges and 3 tailpieces. One set is the original, but the chrome is nasty looking. The other set is new OEM replacement but isn't quite to spec from what I can tell, and the tailpiece is heavier and slightly larger. And the third set I just bought off ebay, supposedly came off mid 70s gear, and the bridge looks good but seems flipped the wrong way for where the string grooves are, and the tailpiece is heavy like the replacement one I bought.

================================================================
Off course you should care bro. I like it too - great tone if set up properly.
I think some people flip the bridge around in an attempt to clear the rear edge of the bridge from rubbing the dead strings. But obviously you shouldn’t do that, since intonation will go out of whack.

The Schaller made Wide travel tune-o-matic bridge (aka ”harmonica bridge”) sits perpendicular to the strings and therefore, contrary to an ordinary off-set (angled) ABR-1, requires wide travel saddles for intonation. Hence, the bridge is wider and won’t allow too steep a break angle. (Don’t ever replace the Schaller bridge with any of those replacement Nashville style bridges made to fit the Schaller poles – the guitar won’t intonate since the thin chassis tune-o-matics are designed to be off-set mounted and not perpendicular.)

A steep break angle was never an issue with the stock configuration properly set up. The original 70’s SG’s had “exclusively low frets” and 3 degree neck angle. When people have replaced worn out frets with tall frets, obviously the bridge needs to be raised. If then, the strings rub the rear end of the bridge the proper solution is to raise the stop tail piece.
It’s common that people flip an ABR-1 for intonation purposes. But there is seldom a need to flip a wide travel bridge, since there is plenty of room for the wide travel saddles to be adjusted and intonated. However the slots extends a bit further at the rear end, so you could flip the bridge chassis in the unlikely event you would need more space for forward adjustment. If you do that, you would also need to remove and flip each bridge saddle. It’s very important that the saddle slots fit each individual string, assuming you want optimal tone and sustain.

Now, time for intonation:
The Schaller bridge is not really tune-o-matic compared to an ABR-1 and cannot be adjusted on the fly. (It doesn’t have the thumb screws and there are screws on both sides that need to be turned for intonation.) But it’s not that hard to intonate and once set up, it normally requires a minimum of maintenance.
Sometimes Gibson put a drop of lacquer on the intonation screw heads to prevent them from loosening. You would need to break that seal in order to adjust the saddles.

1. Remove the bridge. Use two flat screw drivers, one on each side. Loosen by turning anti clockwise. First time you need to apply some force (or maybe a solvent) to break the lacquer seal. Apply some oil as well. But be careful so that you don’t hurt yourself or break anything
2. One of the screws works a lock screw – it’s actually a nut. (Once loosened several turns, you can turn the opposite adjustment screw to move the saddle.) If you need to remove the saddles; Remove the lock screw completely and remove the saddles by turning adjustment screw anti clockwise, all the way out.
3. Set the saddles the way you want them. Put the bridge back in place and restring the guitar.
4. Loosen the lock screws, adjust saddles to intonate. Once intonated, tighten the lock screws.
"Do not write so that you can be understood, write so that you cannot be misunderstood." -Epictetus

First show: 8/16/69 (Woodstock)
Last show: 3/19/95 (Unbroken Chain breakout)
Member of the Four-Decade Club
Charter Member, President & CEO of OAD (Order of the Ancient Deadheads)
User avatar
TI4-1009
Senior Member
 
Posts: 1561
Joined: Fri Aug 20, 2010 6:27 am
Location: Upstate NY- Toodaloo

Re: Harmonica Bridge

Postby mgbills » Thu Nov 29, 2012 9:13 am

Awesome. Pete B. has my Tiger LP that I had the wide Harmonica bridge installed on. The intonation was wacky and giving him trouble. When I get it back next week this will help!

Peace
M
"Hi Ho...the Carrion Crow...FoldeRoldeRiddle"
User avatar
mgbills
Senior Member
 
Posts: 829
Joined: Thu Apr 29, 2010 12:04 pm
Location: The Northwest Corner

Re: Harmonica Bridge

Postby softmachine72 » Wed Dec 05, 2012 2:57 am

I can see why Jerry used these bridges they have plenty of travel for intonation and rock solid. Plus when you move the saddles it does not change angle dramatically. You can also change the saddles w/ the graph techs w/ minor mods.. you can flip the bridge but you will have to set the intonation. does any one know where to get titanium or steel replacements?
User avatar
softmachine72
Billy
Billy
 
Posts: 235
Joined: Wed Mar 17, 2010 1:11 am
Location: Dallas Tx

Re: Harmonica Bridge

Postby TI4-1009 » Wed Dec 05, 2012 7:15 am

I find with mine that some of the strings touch the back edge of the bridge- heading down to the tailpiece. Not sure if that's critical, or even important, but I think you want the strings to be free where ever possible. Tailpiece has the wood riser, but maybe should be a little thicker?
"Do not write so that you can be understood, write so that you cannot be misunderstood." -Epictetus

First show: 8/16/69 (Woodstock)
Last show: 3/19/95 (Unbroken Chain breakout)
Member of the Four-Decade Club
Charter Member, President & CEO of OAD (Order of the Ancient Deadheads)
User avatar
TI4-1009
Senior Member
 
Posts: 1561
Joined: Fri Aug 20, 2010 6:27 am
Location: Upstate NY- Toodaloo

Re: Harmonica Bridge

Postby mgbills » Wed Dec 05, 2012 8:46 am

I'm about to try & figure that one out. I had a Les Paul Tigerized a while back by Andrew Olson. Before I started converting strats. Andrew & I didn't discuss string action (I was probably hasty), and it came back with nice low action. I didn't check the intonation at the time.

Long story short (and epic diatribe)...I decided to raise the action to Jerry standard. I built a spacer because it just didn't seem right to have the strings fret out on the harmonica bridge. I loaned the LP to Pete B. while I overhauled his Tiger/Strat (...I wish I could type Tigerstrat). I thought Pete would only have it for a couple of weeks, but do to some part sourcing issues it's been a couple of months. Apparently it's got intonation issues. The Peterson & I shouldn't have done Brother Pete wrong in that way.

Here's the odd thing. When the strings break over the saddles on a Strat...the first thing they encounter is the metal on back of the saddle/intonation slider.

I am also coming to discover that Strats only get close to proper intonation with the action set at 7/64" at the 12th fret (Gary Brawer Tiger spec). I have 3 currently in my possession. Pete's, another customers (specifically in for intonation), and my personal Stat. The low E & G strings remain slightly sharp at the 5th & 17th, with the strings shortened as much as possible (saddles all the way back). I moved the string action down to approximately 7/128th (1/2 of a 64th to the limit of my eyeballs), and the intonation improved. I think that it's very likely that each guitar type (LP, Strat, etc) will intonate best within a range. This point is likely obvious to some here, but it has been fascinating to derive that conclusion.

Can't wait to get the LP back. Everything plays into intonation. Nut. Neck relief. Dimensions of fret wire. Bridge height. Saddle position. And...likely what happens to the string once it breaks over the saddle.

I was pondering all this as I watched the Peterson spin back and forth last night. Sitting at the bench with my index finger doing the seaweed dance around the 5th fret of the G string. (Man! I really like that line!) But seriously...how you fret can effect intonation by amost 1/2 a semitone. Come to think of it...if you fretted the guitar just past the preceding piece of fretwire....it would be almost a whole semitone (genious I am :-) )

But specifically, even when you fret with your fingers touching the upper fret, the quality of the note varies greatly with pressure & position. The higher the action the more the string is lenthened by fretting.

Ok. Time for a new thread. When I have a nice tight synopsis I'll start a new thread. I should drink more coffee before I type.

Peace
M
"Hi Ho...the Carrion Crow...FoldeRoldeRiddle"
User avatar
mgbills
Senior Member
 
Posts: 829
Joined: Thu Apr 29, 2010 12:04 pm
Location: The Northwest Corner

Re: Harmonica Bridge

Postby TI4-1009 » Wed Dec 05, 2012 12:01 pm

Yeah, on the surface intonation is easy- just the distance between the nut and the bridge. Then all hell breaks loose.........
"Do not write so that you can be understood, write so that you cannot be misunderstood." -Epictetus

First show: 8/16/69 (Woodstock)
Last show: 3/19/95 (Unbroken Chain breakout)
Member of the Four-Decade Club
Charter Member, President & CEO of OAD (Order of the Ancient Deadheads)
User avatar
TI4-1009
Senior Member
 
Posts: 1561
Joined: Fri Aug 20, 2010 6:27 am
Location: Upstate NY- Toodaloo

Re: Harmonica Bridge

Postby JonnyBoy » Wed Dec 05, 2012 4:05 pm

So i'm confused, I have a harmonica bridge, and love it, I need some saddles though. He never really explained the "right direction" for the bridge. With the angle toward the neck or the flat edge toward the neck (the saddles)?
http://otislotus.net/ Finally finished our new site...
User avatar
JonnyBoy
Senior Member
 
Posts: 2134
Joined: Mon Mar 01, 2010 8:35 am
Location: the south swamps

Re: Harmonica Bridge

Postby TI4-1009 » Wed Dec 05, 2012 5:54 pm

Sorry- go to the original thread- there was follow-up:

http://www.everythingsg.com/forum/gibson-sg/19375-bridge-problems.html
"Do not write so that you can be understood, write so that you cannot be misunderstood." -Epictetus

First show: 8/16/69 (Woodstock)
Last show: 3/19/95 (Unbroken Chain breakout)
Member of the Four-Decade Club
Charter Member, President & CEO of OAD (Order of the Ancient Deadheads)
User avatar
TI4-1009
Senior Member
 
Posts: 1561
Joined: Fri Aug 20, 2010 6:27 am
Location: Upstate NY- Toodaloo

Re: Harmonica Bridge

Postby JonnyBoy » Mon Dec 10, 2012 12:45 pm

Ha no shit, Ive had my saddles backwards! But my intonation is awesome, the whole guitar is a gem! I am pretty lucky there.... BUT, I bust strings like a gorilla playing a violin. Maybe that is whats up?
http://otislotus.net/ Finally finished our new site...
User avatar
JonnyBoy
Senior Member
 
Posts: 2134
Joined: Mon Mar 01, 2010 8:35 am
Location: the south swamps


Return to Guitar Building and Mods

Who is online

Users browsing this forum: No registered users and 0 guests