Changed strings from 10 gauge to 9.5s - Trem issue

[Jimcu24]

Hi

I've tried searching the forum for this answer and I cant seem to find the exact info I'm looking for. Basically my PRS Cu24 came with 10 gauge strings installed, I set the neck relief to almost straight and got the action and intonation sorted to my preference and the bridge seemed to be the right height off the body with it parallel to the body. I then changed the strings to 9.5s (although they do seem more like 9's to be honest) and now the bridge tilts backward so that the back part of the bridge is closer to the body than the front part.
I tried loosening the screws on the trem claw and this made the bridge higher off the body and did tilt it forward slightly but not parallel so I lowered it back down so the back of the bridge is the factory spec 1.6mm height off the body. Now though I can't work out how to make the bridge tilt forward so it's parallel with the body, and a couple of my strings seem to have tuning instability ie: when I pick it up to play it I always have to tune a couple of strings. My trem has four springs. I'm wondering if because there is less tension because of having the lower gauge 9's when it was factory setup for 10s now means that there isn't enough tension to pull the bridge forward enough. I am at a loss though what to do next, I haven't touched the 6 screws on the knife edge yet, I'm wary of those!
I just can't find the info in internet land about what exactly to do when the bridge is leaning back, can anyone help me out?

Jim

 

[Michael B]

Don't touch the 6 screws for sure! I think you have to keep going back and forth with adjusting the claw screws and re tuning and adjusting truss rod till you get it in the right spot. You MIGHT need to remove one of the springs but I would keep trying to get it adjusted without removing a spring first. Also there will be a slight intonation adjustment on the saddles...hope this helps!

 

[Jimcu24]

Yeah, maybe there is less pull on the neck so I may have to adjust it to the relief that was there with 10s which would in effect pull the bridge forward? I'll try that and hopefully that will do the trick, with the bridge bending forward it has made my action lower I guess that will self correct once the bridge tilts back. If I wasn't able to fix this with a truss rod adjust and I did have to go from 4 springs to 3, the usual pattern seems to be the 3 springs make a triangle so the middle spring connects to the middle hook nearest the trem claw, however the ground wire is soldered to that hook which makes me feel a bit uneasy in case it wears away the solder and the wire becomes loose...

 

[swede71]

Trem is floating in the middle of equal spring and string tension.What happens when you put on lighter strings is less string tension,in other words springs pull trem back.Put on heavier strings and you will have less spring tension,in other words trem will be tilted forward.In your case you need less springtension to have trem back to floating parallel.No need to adjust neck or pivot screws.It can be a pain in the a** to adjust a floating tremolo so be patience.Two questions for you Jimcu24 to make sure you understand this...If you have trem floating parallel and remove 1 spring,what happens?If you have trem floating parallel and tune down low E string to D,what happens?

 

[Jimcu24]

Trem is floating in the middle of equal spring and string tension.What happens when you put on lighter strings is less string tension,in other words springs pull trem back.Put on heavier strings and you will have less spring tension,in other words trem will be tilted forward.In your case you need less springtension to have trem back to floating parallel.No need to adjust neck or pivot screws.It can be a pain in the a** to adjust a floating tremolo so be patience.Two questions for you Jimcu24 to make sure you understand this...If you have trem floating parallel and remove 1 spring,what happens?If you have trem floating parallel and tune down low E string to D,what happens?

Hi swede71

I would think if you removed one spring it would tilt forward if the strings had greater pull than the trem claw. I havent noticed any visual difference when tuning to drop D. I noticed that the bridge itself was too high off the body maybe over 2mm so I took off the strings and loosened the claw up (but didnt take the springs off) and adjusted the screws slightly lower so the bridge was 1.6mm off the body and made sure they were level and then tweaked the claw screws slightly to bring the back side of the bridge toward the body. So the bridge LOOKS correct. But if you look closely at the screws they don't sit properly in the knife edge holes, the notches underneath the screw head seem to sit slightly backward of the hole. It's hard to explain but if you think of the notch underneath the screw at the rear closest to the saddles it seem to be sitting slightly on the bridge plate and not neatly in the knife edge hole. It seems to stay in tune fine, (although a few cents off on one or two strings after a playing session checked with the strobe tuner), but I dont get why the screws look the way they do.

 

[thesoundstruggle]

SWEDE71, I commend you for being the only one to give tge correct ansewer to such an easy question. In not ragging on anyone. However I think it it is e extremely important that you know 100% what the correct answer is before you post and someone does what was advised when ends up making things worse. Especially when it comes to you PRS and their double action truss rods , they only require about 1/8th to 1/4 of a turn for an adjustment anymore than that can actually seriously harm your guitar or even crack the neck. I would advise you to re adjust truss rod back to where it was, and adjusting the trem screws ( open the trem backplate, I believe there are like 4 of them make sure they are all the same or close to it, adjust them until the trem is about parallel/ flat.

Honestly at this point you maybe better off taking it in to a music shop I would hate it if you accidently turned your trussrod the wrong direction and it snap your neck.

I'll I'm getting at is that if you don't know the answer to yourself, the 1st place you should check is the prs's website, I think it's under support, it will show you the correct way to ajust these things. Also I have noticed on you tube there are videos from the PRS factory with their techs showing you how to do literally every adjustment. I believe next to paying a pro luthier, those videos are the way to go.
Good luck

 

[rabidhamster]

Hi swede71

I would think if you removed one spring it would tilt forward if the strings had greater pull than the trem claw. I havent noticed any visual difference when tuning to drop D. I noticed that the bridge itself was too high off the body maybe over 2mm so I took off the strings and loosened the claw up (but didnt take the springs off) and adjusted the screws slightly lower so the bridge was 1.6mm off the body and made sure they were level and then tweaked the claw screws slightly to bring the back side of the bridge toward the body. So the bridge LOOKS correct. But if you look closely at the screws they don't sit properly in the knife edge holes, the notches underneath the screw head seem to sit slightly backward of the hole. It's hard to explain but if you think of the notch underneath the screw at the rear closest to the saddles it seem to be sitting slightly on the bridge plate and not neatly in the knife edge hole. It seems to stay in tune fine, (although a few cents off on one or two strings after a playing session checked with the strobe tuner), but I dont get why the screws look the way they do.

Might just be your eyes fooling you though if the guitar stays in tune with trem use all night but for a few cents.
Sometimes when you take the strings all the way off the bridge can slip out of the knife edge position. What I do when this happens is detune the strings entirely, but leave them on, and pull the bridge back slightly, away from the knife edge points so you arent marring them, and see if the bridge seems to want to reseat in its grooves. 9 times out of 10 it does.
That 10th time is almost always when someones adjusted the screws before and tried to put them all straight but didnt quiiiite make it. If thats the case you have to make sure there isnt any tension on the bridge against the screws while you adjust them - ie no strings no springs, nothing touching the knife edge on the tremolo while you turn the screw.

 

[Jimcu24]

Thanks for all the replies guys, i've decided to take it to a tech to set it up right so its floating but then actually block the trem (I dont really use it) and I've heard screwing it down can damage the paint and for some reason makes the guitar play weird.

 

[Mikegarveyblues]

Don't know about making it play weird... Stiffer probably. I have my Strat trem against the body (No damage to the finish but that's 1.2" thick poly, lol!). Slightly stiffer to play but not much..