Mustang Setup Step-by-Step ("Aligning the Cosmos")

[Danley]

It's a bit sad when "playing with my Mustang" for an evening has meant for me things other than making music (unless tuning and re-tuning counts...) But I've finally put in the time to get my Mustang working, after a long period of it not doing so; the result is that I may now not trade the guitar away. The length of this guide won’t make me a hater eliminator I’m sure, but I’ve written up some essential steps that can eventually lead to a stable guitar with a float for those desiring to do so with a standard bridge:

...

-Start by setting the bridge as low as it can possibly go and still rock fully back and forth, without the baseplate contacting the vibrato plate at maximum ranges of rocking motion. For me this starting point located the bridge ~1mm above the vibrato plate; it was effective to push the bridge forward, raise the screws until the bridge plate was clear of the vibrato plate, then re-center.

(Also, while not ideal for action in general I endeavor for equal height between bass and treble sides of the bridge; this is the best place for the bridge screws to seat in the indentations in the cups, as you're not throwing a hypotenuse/triangle into the bridge width equation)

-Ensure that the vibrato springs are attached to the post indents farthest out from the plate

-Tricky part: Set tailpiece posts to be perpendicular to the body of the guitar under standard tuning, to get maximum range in both directions. Tricky, because:

1- Adjustment of post angle affects tuning, and re-tuning to pitch again will alter the angle of the posts... And...

2- It’s ideal to not turn the tailpiece posts with string tension on the guitar, to prevent wear on the trem pivots (or I should say do that at your own risk.) So that means checking, loosening string tension, re-tuning, re-checking... Uggh.

-At this point the cigar *should* be high enough that strings tuned to standard pitch won't contact the back of the bridge; in the ideal scenario you’ll have about 0.5mm above the baseplate to any string (that way there won’t be any contact of the string with the plate throughout the range of motion). The high E string is most prone to touch the plate. Remember though, we already set the bridge to the lowest possible position. You have options if the tailpiece is vertical and strings touching the back of the bridge at this point: A.) Move to lighter guage strings and start the process over, or B.) settle on losing your perfect vert. float, just adjust the thing higher to where it clears, and continue.

FYI... I found a decent balance with Ernie Ball elevens, but feel like tens would make things easier, due to higher tailpiece height necessary to counterbalance the springs (meaning that there’s not such slight clearance between the strings and the plate.) I feel like twelves would probably over-cook it and not let you set the tailpiece high enough, but haven't tried it myself.

-IF you have room (and be mindful that this is not guaranteed depending on your string gauge/brand), raise the bridge to where no string is closer than a 0.5 mm distance from the baseplate. This will give you max. string tension and break angle. Notice that as yet we’ve given no thought to the overall above-the-neck action; that’s on purpose, we’ll get there... FYI my bridge wound up 1.4mm from the vibrato base at final setup.

...Also, and keep this in mind throughout this whole process if you haven't guessed, raising/lowering the bridge will always affect tuning, and re-tuning will cause the tailpiece to no longer be perpendicular to the body. And then, adjustment of the verticality of the tailpiece will affect the tailpiece height (and tuning), so you’ll probably need to tweak it more, and may wind up messing with the bridge/tailpiece a dozen times in total <-(my warning). My tailpiece, FYI, wound up almost exactly 3/16" above the vibrato base <-(my baseline suggestion, with elevens).

(Final note here, it's important that both posts be of precise equal height above the vibrato plate, or trem operation will not be smooth. A hair off could make it wonky.)

-So let’s presume you’ve got a bridge high enough to float and provide maximum break angle, and tailpiece cigar high enough that the strings clear everything, and your tailpiece posts are vertical. Congratulations I guess for sticking with it this far, and happy eighty-fifth birthday.

Now we can adjust the overall action of the guitar. We will accomplish this not by adjusting the bridge at all (thank god), but by adding or removing shims to the neck pocket. If you’re like me, your action came out a bit high, so you want to add a shim. After experimenting a bit, I wound up using a 3mm narrow sliver of credit card (expired works better) set at the very bottom edge of the neck pocket. This got me to ~1.5mm action above the 12th fret. Most people will probably want it higher, but really this guitar has a 7.25” radius and tiny frets so fuck bending anyway.

...And finally, as always messing with shims has some likelihood of causing your tailpiece to go slightly out of whack. Make small tweaks to the posts if this is the case, tune the guitar, center the bridge, check for verticality of the posts, check for string clearance above the baseplate, re-tune, and repeat.

-Not to go too deep into “intonate the guitar,” “make sure your frets aren’t dented to shit” or “know how to set your truss rod,” something to keep a mind on while you now work on the nut, because without a very precise filing of the nut the guitar won’t stay in tune; the issue is sensitivity of other strings to one string de-tuning:

You know how the Mustang trem is really good at doing Floyd style flutters (even accidentally), and has such smooth, silky, easy effort? That’s because the springs are of such loose tension. That also means that just a slight change in tension (aka loss of tuning in one string) can push all the other strings out of tune by a quite large degree; in other words, one bad nut slot can ruin it for all five other strings, and just because you have a string where the tuning is slipping doesn’t mean that it’s that string slot fouling things up.

-LAST step. Make sure the bar isn’t pushed in so far that the end contacts the vibrato plate. Can seriously mess with tuning. Flutter, divebomb, and pinch harmonic squeal away.

...

Of course all guitars will be somewhat different vs. the dimensions I’ve put forward and the capabilities/clearances, and of course since the Mustang trem has greater range than almost any other non-locking trem (you can even set it to slack the strings, although not with a float) going absolutely crazy on the bar, pulling up as far as possible etc. won’t be the greatest thing for tuning... But set up in this way, you won’t have things like binding strings or loose bridges, and have some capability of staying in tune with vibrato use.

When I get less lazy and am enthusiastic about taking this stupid thing apart again, I’ll probably switch to tens and try to file down/restore the pivot edges (if they need it). Feel free to offer any other input or hints

[BolanRox]

i know it comes down to set them where it sounds good to you, but is there a recommended / suggested starting point for pickup heights?

[Danley]

Depends on strength of pickup magnets etc, and whether or not you're using the standard covers, which further separate the magnets from the strings physically.

I have hot A5 singles in mine, and am able to to raise them to within 1mm of the strings fretted at the 22nd without any string pull issue. In general I go as high as possible without hearing warbling or quick decay of notes on higher frets, then adjust downward to balance sound between pickups from there.

[BolanRox]

Thanks! I have the stock Duncan Designs now - I already raised up the bridge a good bit to get it to match up with the neck PU - I will raise it some more tonight until it stops sounding good i guess

[BolanRox]

I was shocked how high i could crank them up i feel like i could maybe even go a touch higher but for now its sounding great!

[jc808]

Wow, thanks for writing all this up. Think this is what it took to finally convince me that I don't need a Mustang

[raindog13]

Wow, thanks for writing all this up. Think this is what it took to finally convince me that I don't need a Mustang

My thoughts exactly. Yikes. Oh well.

[supersonicjazzmaster]

Oh! This above sounds complicated.
Thanks for writing this all down!
I don´t understand everything correct I guess..
...I have 6 or 7 Mustangs these days...
On most of them the trem unit works perfect. I never had problems with 60´s Mustangs.
Old trem units (mid 60´s) seem to work better. Maybe better spring material!?

On my two Japan (a MIJ and a CIJ) everything worked good for a few years.. suddenly they got out off tune often...
Still working on getting them good again..
With the guidance above I will try it again.

[HarlowTheFish]

Oh! This above sounds complicated.
Thanks for writing this all down!
I don´t understand everything correct I guess..
...I have 6 or 7 Mustangs these days...
On most of them the trem unit works perfect. I never had problems with 60´s Mustangs.
Old trem units (mid 60´s) seem to work better. Maybe better spring material!?

On my two Japan (a MIJ and a CIJ) everything worked good for a few years.. suddenly they got out off tune often...
Still working on getting them good again..
With the guidance above I will try it again.

It's partly the springs, but mostly the plate -- the old ones use harder metal and have knife edges where the posts go through, so there's actually somewhere for the posts to rock on properly. A lot of the newer Mustangs have worse metal and no edges, so it's kind of a crapshoot to get it to work well, and eventually the metal's gonna buckle or deform at the posts and you're kinda boned at that point.