594 bridge collapsing

[SinSir]

I am hoping it isn't something we are going to start seeing on these. My SC-58 and 594 have both had string tension on them for a good while and are both still straight.

This bridge setup has been out for a good while now. If it was a widespread concern we'd hear more about it. I also have enough confidence in PRS that they'd address the issue well before continuing to pump them out.

Still going to check out my Stripper 58 when I get home.

 

[JasonE]

This bridge setup has been out for a good while now. If it was a widespread concern we'd hear more about it. I also have enough confidence in PRS that they'd address the issue well before continuing to pump them out.

Still going to check out my Stripper 58 when I get home.

I think they would take care of it if it became a wide spread issue. I am just wondering how many people may have the issue but have not noticed it yet. My bridges are the older version that have the flatter saddles in them. I was thinking that I had read somewhere that they had made some changes to the bridge after the first ones other than the saddles. I thought it was a change in the metal they are made of.

 

[László]

I am guessing string pressure is the cause of the issue. The material they are casting them out of may be just a little too soft to stand up to the string tension over time. This would happen faster with heavier strings. They may have had a batch that was softer or may need to alloy the metal a bit with something a little harder to stop this from happening. I am hoping it isn't something we are going to start seeing on these. My SC-58 and 594 have both had string tension on them for a good while and are both still straight.

Could be. It's anyone's guess until they get it figured out, which obviously they need to do.

 

[John F]

Notice that the screw holes have the same radius as the saddles which match the fret board radius. The shape of the block is meaningless, and that hunk of metal doesn’t look like it has bent by the string pressure as there is very little force. Plus the force would pull it up away from the body, not down into the body. My humble opinion is it was cast that way and is very strong. Other than it being displeasing to the eye, there is nothing wrong with it as a bridge. Take it off and try to flex it, I bet you will find it rigid.

 

[jak3af3r]

I remember now why I never went with the ABR-1 on the LP I had. You should see how bad those bend.

 

[JasonE]

Notice that the string holes have the same radius as the saddles which match the fret board radius. The shape of the block is meaningless, and that hunk of metal doesn’t look like it has bent by the string pressure as there is very little force. Plus the force would pull it up away from the body, not down into the body. My humble opinion is it was cast that way and is very strong. Other than it being displeasing to the eye, there is nothing wrong with it as a bridge. Take it off and try to flex it, I bet you will find it rigid.

I think you misunderstood the problem. The bridge is bent. It most definitely does cause an issue. The saddles were made to match the radius of the fretboard but now that the base is bent, they don't match. The D and G strings are now closer to the fretboard than they should be. That means he may be getting string buzz on those two strings and the only way to fix it is to raise the entire bridge until it stops. That could make the other four strings higher off the fretboard than is comfortable to play.

 

[Maxime Bousquet]

Whatever the reasons, I see it bent too, it's strange due to the age of the guitar. perhaps a failure in the alloy of certain batches? The gibson ABR-1 bridge is thin and will eventually bend but it takes years..

 

[SinSir]

I think they would take care of it if it became a wide spread issue. I am just wondering how many people may have the issue but have not noticed it yet. My bridges are the older version that have the flatter saddles in them. I was thinking that I had read somewhere that they had made some changes to the bridge after the first ones other than the saddles. I thought it was a change in the metal they are made of.

I have flat saddles too. Good point on I wonder what else was changed in material or even suppliers over the years? Pretty sure I'm not alone in this.. I checked my bridge as soon as I got home today. Straight as can be on my Stripper 58.

 

[RCM78]

Actually, that's concave, not convex, unless you're looking at it upside-down.

You are correct. I took two other pictures of the fret rocker on the underside of the bridge showing it to be convex. I sent them to the dealer but didn't post them here because the dealers name is in the pic.
Short answer... I got confused...

 

[RCM78]

Spoke with the dealer today. PRS is sending me a new bridge.
So here's the issue as I see it. In 2020 (the year of this guitar) PRS changed the bridge design and made it thinner. My 2019 594 bridge is noticeably thicker and has two "stepped" sections for it to rest on the thumbwheels. I doubt that one will collapse.

Since this guitar is used I don't know what strings the previous owner had on it. Maybe they were heavier. If the stop tail was lowered to the body that will cause more downward pressure on the bridge increasing the chance of it collapsing.

I noticed the issue shortly after getting the guitar. I replaced the strings and was giving it a set up when I noticed the string radius wasn't following the fretboard radius.
Now here is the concerning part. I texted a friend the picture of the bridge. He also has a 594 with the thinner bridge. His is also bent. What are the chances?

I'm sure PRS will make good if it's a widespread issue but at this price point this is more expected from Gibson than PRS...

 

[RCM78]

So far I've seen three versions of this bridge. Flat saddles with stepped base (probably the strongest version). Flat saddles with flat bottom base, and tall LP style saddles with flat bottom base.

 

[László]

You are correct. I took two other pictures of the fret rocker on the underside of the bridge showing it to be convex. I sent them to the dealer but didn't post them here because the dealers name is in the pic.
Short answer... I got confused...

I get confused every darn day about something!

 

[bodia]

I get confused every darn day about something!

Yeah, I get that. I have the same issue. Usually, it’s ”what day is it?”

 

[andy474x]

I can’t remember if I had posted about it here or not, but I noticed this on my ‘19 bridge recently, too. I was also noticing that the open string sustain was, not bad, but maybe not as good as it should be for a guitar of such quality, and the low strings were warm sounding and not as piano-like as I’d have preferred. Always thought it was just the guitar, but for the heck of it one day I decided to swap out the bridges on the core and S2, and whaddya know, the core bridge was bent. Totally came alive with the S2 bridge, to my surprise.

I tried to hand bend the core bridge back some, and didn’t visually see where I’d made a difference, but the guitar still rang out longer and clearer am when I put the core bridge back on. For peace of mind, I ordered a new bridge from PRS and put it on, and it’s still sounding fantastic.

I assume that the bend was creating a bad contact point on the thumbwheel post and affecting vibration transfer. Maybe adjusting the bridge up, or the tailpiece down, under string tension could’ve done it? But I kinda think mine was always like that (purchased new) because it always sounded that way, and now it sounds better. Don’t get me wrong, it sounded good before, but there was always that little something.

The new bridge I got from PRS had the triangular cross section saddles, rather than the block style, which I found interesting, the accessory store even shows the block saddles. TBH I prefer the triangular saddles, so, cool. The bridge itself is plated/polished on the bottom, whereas the older one that bent was raw, unpolished - interested to see if the others that bent are like that.

 

[RCM78]

I can’t remember if I had posted about it here or not, but I noticed this on my ‘19 bridge recently, too. I was also noticing that the open string sustain was, not bad, but maybe not as good as it should be for a guitar of such quality, and the low strings were warm sounding and not as piano-like as I’d have preferred. Always thought it was just the guitar, but for the heck of it one day I decided to swap out the bridges on the core and S2, and whaddya know, the core bridge was bent. Totally came alive with the S2 bridge, to my surprise.

I tried to hand bend the core bridge back some, and didn’t visually see where I’d made a difference, but the guitar still rang out longer and clearer am when I put the core bridge back on. For peace of mind, I ordered a new bridge from PRS and put it on, and it’s still sounding fantastic.

I assume that the bend was creating a bad contact point on the thumbwheel post and affecting vibration transfer. Maybe adjusting the bridge up, or the tailpiece down, under string tension could’ve done it? But I kinda think mine was always like that (purchased new) because it always sounded that way, and now it sounds better. Don’t get me wrong, it sounded good before, but there was always that little something.

The new bridge I got from PRS had the triangular cross section saddles, rather than the block style, which I found interesting, the accessory store even shows the block saddles. TBH I prefer the triangular saddles, so, cool. The bridge itself is plated/polished on the bottom, whereas the older one that bent was raw, unpolished - interested to see if the others that bent are like that.

Well, That's three that we know of that were bent.

 

[John F]

Here's a couple pics. The bridge should be flat. This one is clearly concave.

Lets put some facts in here:

The Curt Mangan String website shows the 10 to 46 string set pulls a total force of 97.54 pounds force between the tuner and stop tail on a 24.75” neck at standard E tuning. The strings individually exert the following force between tuner and stop tail:
E 15.26 lbf, B 14.48 lbf, G 15.61 lbf, D 17.34 lbf, A 18.39 lbf, E 16.46 lbf

The down force at the bridge saddle is a fraction of that given the ratio of the rise of the saddle above the stop tail and the total length of the string. It is relatively easy to lift a string off the bridge saddle proving the down force is minimal. Try it if you doubt. The brass screws holding each saddle look to be 6-32 and measure 0.1225 inches in diameter between the valleys of the thread pitch. This little screw is not sheared or bent in any guitar saddle I’ve ever seen or worked on. So tell me how this small amount of force bends a ruggedly built saddle but not the screws? The screw heads in your photo show the fret board radius in height above the body relative to your fret rocker. In other words, the 3rd and 4th screws are closer to the fret rocker than the outside screws. If the bridge was collapsed the screw heads would be low in the center because they are farthest from the ends of the bridge, and they are not. Also, the saddles in your photo show the same fret board radius. I looked at my 594 bridge and checked the screws and saddles with a radius gauge and they match a 10 inch radius. The curvature in my bridge matches your photo side by side.

What you see is a casting that is not machined perfectly flat on the bottom or top. But look closely, the screw heights above the body are drilled into the bridge and this is what sets the radius of the bridge, not the bottom of the bridge or the top of the bridge. Each screw position thus sets the saddle height above the body relatively string to string and your photo looks perfectly fine to me. Obviously the saddle height screws on each end of the bridge set the ultimate saddle and string heights.

PRS or the store may send you a new bridge, but it would be to make you feel better by sending you a better looking product. I believe the Saddle heights will remain the same old bridge to new. If I had your bridge and the strings checked with a radius gauge were 10 inch, I wouldn’t replace my bridge. You can’t bend that rugged saddle with guitar playing. Same relative forces apply to a similar neck length and string gauge on an acoustic. Does guitar playing crush the top? No

 

[Draconomics]

My bridge is made from a twig and hopes. That's all I can add to this, bye.

 

[ViperDoc]

Look at the edge that is on the table. It is definitely bent.

I bet the table ain’t quite as straight as your straight edge. If you have a relief gauge, try testing the relative heights of the saddle channels. I understand the suspicion that your bridge is bent, but if you’re looking at factory surfaces that are the result of shaping and tinning, they won’t affect the ability of the bridge to hold the saddles at the correct heights.

Was the guitar dropped? String tension and palm pressure are not strong enough to defy the liquid-solid properties of metal alloy physics, even if you were playing this guitar daily in Dubai (the desert).

 

[RCM78]

Lets put some facts in here:

The Curt Mangan String website shows the 10 to 46 string set pulls a total force of 97.54 pounds force between the tuner and stop tail on a 24.75” neck at standard E tuning. The strings individually exert the following force between tuner and stop tail:
E 15.26 lbf, B 14.48 lbf, G 15.61 lbf, D 17.34 lbf, A 18.39 lbf, E 16.46 lbf

The down force at the bridge saddle is a fraction of that given the ratio of the rise of the saddle above the stop tail and the total length of the string. It is relatively easy to lift a string off the bridge saddle proving the down force is minimal. Try it if you doubt. The brass screws holding each saddle look to be 6-32 and measure 0.1225 inches in diameter between the valleys of the thread pitch. This little screw is not sheared or bent in any guitar saddle I’ve ever seen or worked on. So tell me how this small amount of force bends a ruggedly built saddle but not the screws? The screw heads in your photo show the fret board radius in height above the body relative to your fret rocker. In other words, the 3rd and 4th screws are closer to the fret rocker than the outside screws. If the bridge was collapsed the screw heads would be low in the center because they are farthest from the ends of the bridge, and they are not. Also, the saddles in your photo show the same fret board radius. I looked at my 594 bridge and checked the screws and saddles with a radius gauge and they match a 10 inch radius. The curvature in my bridge matches your photo side by side.

What you see is a casting that is not machined perfectly flat on the bottom or top. But look closely, the screw heights above the body are drilled into the bridge and this is what sets the radius of the bridge, not the bottom of the bridge or the top of the bridge. Each screw position thus sets the saddle height above the body relatively string to string and your photo looks perfectly fine to me. Obviously the saddle height screws on each end of the bridge set the ultimate saddle and string heights.

PRS or the store may send you a new bridge, but it would be to make you feel better by sending you a better looking product. I believe the Saddle heights will remain the same old bridge to new. If I had your bridge and the strings checked with a radius gauge were 10 inch, I wouldn’t replace my bridge. You can’t bend that rugged saddle with guitar playing. Same relative forces apply to a similar neck length and string gauge on an acoustic. Does guitar playing crush the top? No

And yet this is a common documented problem on Les Paul bridges.
Let’s look at the facts.
The bridge should be flat, it isn’t. It collapsed in the same direction the strings direct their force.
The string radius did not follow the fretboard radius.
A PRS rep reviewed my pics and is sending a replacement.
Your opinion on this matter is irrelevant.

 

[John F]

And yet this is a common documented problem on Les Paul bridges.
Let’s look at the facts.
The bridge should be flat, it isn’t. It collapsed in the same direction the strings direct their force.
The string radius did not follow the fretboard radius.
A PRS rep reviewed my pics and is sending a replacement.
Your opinion on this matter is irrelevant.

Scoff all you want, my skin is not that thin. A word of advice, you shouldn’t try to flame someone who is trying to help you. My analysis may be irrelevant to you, but the physics involved would prove you wrong. Need you be reminded that you are not using a Les Paul bridge? PRS sending a replacement bridge is to their credit to always keep the customer happy, and it is cheaper and faster than having you send the guitar into them for analysis. Plus, you never said you experienced any problems with playing this new to you guitar, just that it looks different and you are dissatisfied. Consider also that you are trying to fix a problem that does not exist.

Install that new bridge then take the old one and purposely bend it, if you can. I bet you won’t be able to without a vice holding one end and a large wrench on the other. PRSh wouldn’t allow a flimsy bridge design out the door.

Feel free to disagree, but be nice.