1966 Vintage Jaguar restoration

[fendermcfenderface1!]

So I've got this '66 ( neck heel date ) Jag I'm trying to restore. All original parts. I'm missing one bridge height screw, and I've searched the web hi and low. Fender is no help. Reverb, eBay, Allparts, etc etc. I finally broke down and bought a Vintage Fender Mustang Reissue bridge, 7.25" radius, from Angela, as at least the 2 screws height screws on it have the pointed end to allow the bridge to "float" in the thimbles in the body, thinking that for $50 I'd at least get the screw I need. And a spare. Now I find though the screws do have the pointy end, the threads are different and won't work in the original '66 bridge.

I can just go on and use the Mustang bridge, the post spacing does at least match the thimble spacing in the body; but although the U channel of the bridge does match the 7.25" radius of the fingerboard, both E saddles are way lower than the A,D,G and B saddles, and the saddle heights are not individually adjustable. So how in the world do you adjust the E strings to the correct height? I know bridge replacements on Jags is a common mod, any advice appreciated!

[andy_tchp]

That Mustang bridge should be fixed at 7.25" radius.

The baseplate of the bridge that the saddles sit on should be completely flat and not have any radius at all, so this is very confusing.

[timtam]

Vintage and MIA modern bridge height grub screws are #4-40. I believe that vintage ones were around 3/8" (9.5mm) long (but I only have one 60s bridge on hand to measure). Modern ones are longer, around 1/2" (12.7mm). Longer is better.

The same diameter screws (#4-40) are used in all Fender MIA offset bridges. The (modern) part number is 0056157049, as in all offset guitar parts manuals in recent years. If you google that number you'll see some of the the guitars that have those screws (but some parts manuals do not break down the bridge into all its component parts numbers).

I just took that screw from the post of a current Am Pro bridge (9.5" Mustang-style) and inserted it into the post on the early 60s L-series jaguar bridge I have. It fits - the threads are the same.

Fender appears to often use '49' as the last numbers on parts on actual guitars, and 00 for the aftermarket part. So the aftermarket part number should be 0056157000.

If Fender were unhelpful, they were either choosing to be unhelpful, or are clueless.

Here are 3 sources of those screws, that Fender supplies to parts resellers:

https://www.ebay.com/itm/334817614753
https://www.guitarpartsfactory.us/005-6 ... 0056157000
https://www.ebay.com.au/itm/314736381111

I would have expected that the modern Mustang bridge you bought would be MIA and have the same screws. But if it is MIJ or MIK, the screws would be metric (M3). But those should be too big to fit in the post at all (#4-40 diameter is around 2.7-2.8mm), not just be the wrong thread. Note that the fit of screws on modern bridges can be tighter than on vintage bridges. So screws can be harder to turn on modern bridges, and even seem like they might not be the right fit. Of course trying to force them if you're not 100% sure they're the right size is not a good idea.

Also, the 0.05" (1.27mm) allen key required for #4-40 grub screws can be hard to insert into a #4-40 bridge height screw in a post, leading you to think that the screw or the allen key size might be wrong.

[andy_tchp]

I would have expected that the modern Mustang bridge you bought would be MIA and have the same screws.

I wouldn't. If it's this one (which was the only Fender branded option for decades) it's 100% Made in Japan:

Fender Mustang Vintage Reissue Bridge, 0035555000

[fendermcfenderface1!]

Thanks fellas for helping me out here.

Timtam- I already bought those screws, they are way bigger than the two ( I only have one, hence my dilemma) in my original vintage '66 bridge. The one original bridge height adjustment screw I have, that rides in the thimble, is 9.25mm long. The Mustang screws are 15mm long. I could use the whole Mustang bridge, but no way to adjust individual string heights with that one.

Andy- yes, that's the exact Mustang bridge I bought- the base plate of the U channel is flat, the sides are at the 7.25" radius, but as you can see in the link you sent, the E string saddles sit way lower than the other four; no way to adjust individual heights like in the "66 bridge.

I really didn't want to put a Mustang bridge onto a straight vintage 1966 Jaguar restoration- I only wanted one vintage 1966 Fender Jaguar bridge height adjustment screw so I could use the original '66 floating and fully adjustable bridge. One freaking tiny screw I can't find anywhere! I only bought the Mustang bridge, thinking that was the only way to get the one screw I need so I could use the '66 bridge- but the threads don't match.

Maybe I'm overthinking it- maybe the Mustang would work fine, the guitar is still in pieces so I can't say. Just wish I could find one screw to keep it 100% original.

[timtam]

Timtam- I already bought those screws, they are way bigger than the two ( I only have one, hence my dilemma) in my original vintage '66 bridge. The one original bridge height adjustment screw I have, that rides in the thimble, is 9.25mm long. The Mustang screws are 15mm long. I could use the whole Mustang bridge, but no way to adjust individual string heights with that one

The #4-40 screws I linked are 1/2" long (12.7mm); that spec is confirmed in one of the links (below). I measured the same length, and tested that same-part-number #4-40 screw (from my modern Am Pro bridge) in my 60s jag bridge, in place of its original #4-40 ~9.5mm screw. That length was fine. Vintage bridge posts and modern ones are the same length. But the vintage posts feel like they are not threaded as far up inside the post as modern posts (I screwed in and out a few times to clear any old gunk in there, to get to the longer screw to maximum insertion point). That 12.7mm screw protrudes ~1mm out of the bottom of the post when fully threaded. That was fine for my bridge height (but I guess you could always tap the thread further up inside the vintage post with a 4-40 tap). Of course you wouldn't want the screw to be in much further, or the bridge would rock on the bottom of the post rather than the conical tip of the screw.

I'm guessing Fender changed to ~3mm longer (and tapped the post threads higher up) because those few extra mm are actually useful, particularly for higher bridges (where the screw needs to protrude further). 15mm long screws like your Mustang ones might well be too long for some vintage bridge setups (but also if they are the wrong, (MIJ?) metric, M3 diameter).
https://www.ebay.com.au/itm/314736381111

But you can buy #4-40 conical tip grub screws in various other lengths. Threads (TPI) are highly likely to be consistent, but you would need that measured to be 100% sure. eg
https://www.ebay.com.au/itm/202411474957

Screw lengths are not set in stone. I use what actually works best. On metric offset bridges in particular I often swap for shorter intonation screws (16mm in place of 18mm, rarely even 14mm; vintage imperial length was ~15.9mm) that are less likely to foul the string with their tip, shorter saddle height screws (8mm in place of 10mm and 6mm in place of 8mm) that don't dig into your hand, and longer bridge height post screws if necessary to still be firmly threaded at the bridge height I want.

[MrSparkle]

Andy- yes, that's the exact Mustang bridge I bought- the base plate of the U channel is flat, the sides are at the 7.25" radius, but as you can see in the link you sent, the E string saddles sit way lower than the other four; no way to adjust individual heights like in the "66 bridge.

To be clear; that's a feature, not a bug. The idea is the radius is pre-set to the correct shape at the factory and the player can't screw it up! It also means it can't screw itself up - without screws to come loose and sink over time, it won't get out-of-whack. Less places to rattle in use, too. All vintage and most modern Mustang bridges are like this. This is also part of why so many people use Staytrem bridges on their offsets - and it's the same as the Tune-o-Matic (or Adjust-o-Matic if you're Fender) bridges - which have a a preset 12"ish radius.

Maybe I'm overthinking it- maybe the Mustang would work fine, the guitar is still in pieces so I can't say. Just wish I could find one screw to keep it 100% original.

If you prefer flatter strings, you can put a 9.5" bridge on your guitar, I guess? And that's a hypothetical you, I'm not suggesting you actually do it. The Mustang bridge would probably "work" as in the guitar would function - it was a popular mod back in the day, but Mustangs traditionally have a much wider string spacing than Jaguar and Jazzmaster bridges so tend to push the strings too close to the fretboard edges. If you were gonna give up and go this route, the "correct" way to do it is a Staytrem; though if you do like flatter strings, the 9.5" Squier Classic Vibe Jaguar/Jazzmaster/Mustang bridge would also work as that's also 52mm spacing.

But as much as I'm a Staytrem addict on my own guitars, I support the "fully restored" goal; so again - not actually suggesting it. Good luck finding your missing screw!

[fendermcfenderface1!]

Thanks again for all the expert advice available on this site! The luv for vintage guitars is way cool and obvious!

Timtam- I did not realize these small allen head conical screws were available- I suppose I could chase that lead out in order to keep everything original! The one height screw I have is 2.79mm in diameter, vs 2.89 mm diameter for the screws in the Mustang bridge I bought; also the original screw has a courser thread. If the new mustang screws are 4-40 thread, my original is not 4-40. Not sure what thread it is, how would I determine the actual thread of it?

MrSparkle- I hear what you're saying about the Mustang pre set saddles. The Mustang fits in the thimbles, so I think what I'll do is use the Mustang, and if string height adjustment becomes an issue down the road I'll simply swap out the non height adjustable Mustang saddles with my original threaded saddles and height adjustable screws from the original bridge, keeping only the Mustang U shaped channel. I was unaware of the issue with string spacing and the E strings falling off the fretboard- my neck is a B nut width, and 52.38mm at the last fret. The string spacing of both the new and Mustang bridges is identical, at 56mm- I suppose I can deepen the string groove on the E string threaded saddles with a needle file to move them a thread or two away from the edge towards the center. Problem solved! For now anyway.

[MrSparkle]

The string spacing of both the new and Mustang bridges is identical, at 56mm- I suppose I can deepen the string groove on the E string threaded saddles with a needle file to move them a thread or two away from the edge towards the center. Problem solved! For now anyway.

I think you mean the screw spacing! What the threaded saddles give you is the ability to position the string differently for different necks - I would expect on your B neck that the original spacing would have been set around 54mm, like a vintage Strat. But frankly that's a guess. The (other than the cheap aftermarket Mustang copies) like Staytrem, Mastery, Halon have mostly standardised on 52mm though there are exceptions like Trent who use 54mm. The 52mm is the same as modern post-87 Fender, works better for A necks, and gives a bit more space on the fretboard on most necks - which many people find more comfortable.

Good luck, however this plays out over the long term!

Edit: Couple notes, TimTam's grub screws look great - a 3/8" should be perfect if you're happy with the current bridge height. If you wanna double check TPI, you can do that with a set of calipers; vernier, dial or digital in descending order of difficulty. I recently picked up nylon-tip screws for Mustang vibrato arms and had no idea till then that you could just get random sizes of grub screw!

[Matthias]

+1 on what TimTam said. I took apart my own ‘63-ish bridge and took some measurements of a screw with a micrometer to corroborate.

Cone point, matches 4-40 as TimTam says
3/8” long and these work great

McMaster Carr have some options of different lengths for 4-40, but you do have to buy in bulk I think… It might be more economical to pay a high price for 2 than pay out for 25, as you only need one

[andy_tchp]

Hmm.

Yes 4-40 might be 'correct', but I now suspect one of the previous custodians of this instrument has forced a different size and/or pitch fastener into the original bridge base.

[timtam]

The one height screw I have is 2.79mm in diameter, vs 2.89 mm diameter for the screws in the Mustang bridge I bought; also the original screw has a courser thread. If the new mustang screws are 4-40 thread, my original is not 4-40. Not sure what thread it is, how would I determine the actual thread of it?

The Mustang bridge you bought (that Fender markets for Mustang guitars) is almost certainly MIJ as noted above (not any of the MIA Mustang-style bridges with 52mm E-E spacing we typically now put on offsets) ... and therefore its post screws are (metric) M3 diameter as you measured; not the slightly smaller (imperial) #4-40 used on all MIA bridges, vintage and current (which is why the height screws on my current MIA Am Pro bridge thread into the post of my 60s jag bridge). You will also find that M3 grub screws are distinguishable by requiring a 1.5mm allen key, whereas #4-40 screws require a 0.05" allen key (1.27mm).

If you also bought the (modern) Fender (#4-40) bridge post screws as you say (that I posted the part number/earlier links for), what's stopping you using those on your 60s jag bridge ? As I noted, they should screw almost all the way into the vintage posts (with 0.05" allen key), despite their marginally longer length than the vintage ones.

[fendermcfenderface1!]

Thanks again gents for you patience- I'm still learning the lingo.

MrSparkle- by string spacing I meant the string grooves in the Mustang saddles, which are predetermined, unlike the original threaded saddles which might offer a bit of variation by picking exactly where the string lays in the thread valley. What is TPI?

Andy- Nothing was forced in my vintage bridge, the one screw i have takes a .050" allen key and threads smoothly. Problem is I only have one.
What's a "pitch fastener"?

Timtam- the Mustang bridge I bought is Genuine Fender #0035555000, yeah could be MIJ, price was very reasonable, the posts fit the '66 thimbles fine.
I was never concerned about the height screw length, just trying to find one that threaded into the original '66 bridge posts. The height screws I bought separately, #005 6157 000 are too large diameter to fit the original bridge, have a different thread, and do not fit in the Mustang bridge either- too large diameter and too coarse a thread there also. Besides what would be the point of that? The Mustang height screws that came with the Mustang bridge are fine. Where might I find a MIA Am Pro bridge w 52mm string spacing? I am not seeing one anywhere.
Thanks!

[fendermcfenderface1!]

All I'm seeing are 55 mm string spacing and 9.5" radius, my neck is a 7.25" radius.

[timtam]

Timtam- the Mustang bridge I bought is Genuine Fender #0035555000, yeah could be MIJ, price was very reasonable, the posts fit the '66 thimbles fine.
I was never concerned about the height screw length, just trying to find one that threaded into the original '66 bridge posts. The height screws I bought separately, #005 6157 000 are too large diameter to fit the original bridge, have a different thread, and do not fit in the Mustang bridge either- too large diameter and too coarse a thread there also. Besides what would be the point of that? The Mustang height screws that came with the Mustang bridge are fine. Where might I find a MIA Am Pro bridge w 52mm string spacing? I am not seeing one anywhere.
Thanks!

OK so the 0035555000 Mustang bridge you bought is indeed MIJ (link below). So the chances of its post screws fitting a vintage bridge are basically nil. They will be M3 (adjusted with 1.5mm allen key). Vintage is #4-40 (adjusted with 0.05" allen key). So it's also an expected result that the 0056157000 modern jaguar screws wouldn't fit that Mustang bridge.
https://www.fender.com/en-US/parts/brid ... 55000.html
This is Fender's 7.25" radius Mustang-style bridge with 52mm E-E spacing (they call it an "American Professional" bridge even though it's never been on any Am Pro series guitars; it's actually the MIA Marr jag bridge). I am not sure if we've ever had a hard measurement, but I believe it has bigger-diameter post screws than #4-40.
https://www.fender.com/en-US/parts/brid ... 71049.html

So the curious remaining thing is how your 0056157000 screws are too big for your 60s posts. I performed as close as possible to the same test with the screws from my Am Pro bridge (the 9.5" one that has been on Am Pro guitars; and which has #4-40 post screws*) and my 60s jag bridge. Those Am Pro bridge screws have the same part number. And those Am Pro screws and my vintage ones are both clearly #4-40. And both fit my 60s posts

Possible (but unlikely ?) explanations:
- you got sent the wrong post screws
- your 60s MIA bridge is not a 60s MIA bridge (domed tops on the posts is the best test)

It's not really possible that someone might have tapped out your 60s post holes for bigger screws, because then those holes would not be smaller than your screws as you say.

If you could post pics of the 0056157000 screws failing to fit your 60s posts we might get closer to an explanation. Because if we don't, we have no means to tell you which other screws you should buy.

*so the two MIA Mustang-style bridges (7.25" and 9.5") that Fender calls "American Professional" have different lineages, and differ in more features than just radius. And the MIJ one is a whole other different thing again.