Best Quality DA Truss Rod?

[Bruce Johnson]

Is there a "correct" position for the adjuster nut relative to the headstock end? In other words, should the adjuster come as far out into the pitch of the headstock as it can without coming above it, or just so something like 1/8"-1/4" extend beyond the nut, so just the head of it is accessible inside the TRC pocket. Does it matter?

It doesn't really matter; personal taste. You can have it sticking out or recessed. On most of my truss rod installations, I position it so the head is about 1/4" recessed into the hole in the wood. Just to look neat.

 

[John_Nicholas]

I'm not sure I'm crazy about the stainless steel Allied rods. It looks like they are brazed, and I'm not sure that's the strongest option for connecting the threaded block and main section of the rod. That's just my gut reaction, though. They might be fine.

Yes, the Allied rods are brazed. Since you brought up the idea that brazing is not strong, I hoped on Google right away... I just paid $51.00 for this, it better be great!

Found this information on a welding services website.

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Brazing Versus Welding
by [Invalid or Expired Link Removed] on June 19, 2014 in [Invalid or Expired Link Removed]
Brazing and welding are heat treating processes that join pieces of metal together. The primary difference between the procedures is that brazing joins pieces together by melting a filler metal that distributes between the entire connective surface, whereas welding joins pieces together at narrow points by melting them together using a filler metal. When it comes to joining pieces of stainless steel via heat treating, there are important reasons to use brazing instead of welding.

Assembly Joints Are Stronger
Welding creates a strong joint when workpieces that have a narrow point of contact are joined together. However, when workpieces are joined together across a wide point of contact, brazing is preferable. The filler metal distributes between the workpieces and forms a strong bond.

Assembly Joints Are Cleaner
Because it bonds workpieces together by melting them, welding can create messy looking joints that are not suitable for stainless steel assemblies that need a neat, clean appearance. When it is properly performed, the brazing process creates neat, clean joints that have a secure bond.

Better for Thin Work Pieces
Brazing in a controlled atmosphere heats workpieces in a uniform manner, and generally exposes assembly joints to less heat than welding. Thus there is a lower chance that thin workpieces will warp. Steel treating workpieces in a furnace helps to ensure uniform heating.

Better Processing Speed
Because it requires both the base metal and filler metal to melt, welding is a steel treating procedure that generally takes longer to complete than the brazing process. If you have a large work order, forming assemblies using brazing should result in a faster completion time.

[Invalid or Expired Link Removed]
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Well now I feel a bunch better about the fact that the truss rod I have is brazed.

Just an FYI, the Mark Blanchard rods are Stainless steel and here is the process he uses;
"it is made entirely from stainless steel, which means it will not rust or corrode over time. All of the joinery is done by hand with high strength silver solder, thereby eliminating the stress concentration and brittleness associated with welding."

Thanks for bringing up the question.

 

[MPU]

Brazing and soldering use lower temperature material to braze or solder the parts together. Welding melts the base material. Brazing with brass or silver braze is for sure strong enough for a truss rod. I guess silver soldering relates to the material the filler rod is made of.

 

[rudy4444]

Brazing and soldering use lower temperature material to braze or solder the parts together. Welding melts the base material. Brazing with brass or silver braze is for sure strong enough for a truss rod. I guess silver soldering relates to the material the filler rod is made of.

The methods of joining the blocks and rods may be strong enough for the particular application. As long as the user realizes that soldering, brazing, and welding are three different processes based on if the base material surfaces are melted or not then it's easier to have confidence in the long term reliability of the joint. Obviously you have to consider the size of the joint, too.
If you use a method that enables the rod to be easily replaced then it's not a problem if there's a rod failure, other than the logistics of replacing if it's on the other side of the country.

 

[Gilmourisgod]

Hey @John_Nicholas How deep/wide is the slot for the Allied rod? The LMI is exactly 1/4” wide by approx 3/8” deep, but the nut fits in a 1/4” slot too, unlike the BBG/Bitteroot rods, which widen to 3/8”.

 

[John_Nicholas]

Hey @John_Nicholas How deep/wide is the slot for the Allied rod? The LMI is exactly 1/4” wide by approx 3/8” deep, but the nut fits in a 1/4” slot too, unlike the BBG/Bitteroot rods, which widen to 3/8”.

The Allied Rod is 1/4" wide by approximately 3/8" deep and the nut does not need any widening of the channel.

 

[T_Bone_TL]

A quality braze beats a crappy weld 8 days a week, particularly where the joint is designed for it (large surface area, lower stress per unit area.) And most of the welds in this thread are embarrassing (even the non-cracked ones.)

Note that "silver solder" as commonly used in metalworking is actually silver brazing (process above 800ÏF) even though there are now solders (below 800°F) that contain silver in the "lead free soldering" evolution. Mind you, I'm perfectly happy with bronze for brazing, but it does show more than silver, and requires higher temperatures.

Evidently nickle silver (which is actually nickel and copper, no silver) is even stronger and works well with stainless - but at higher temperatures yet.

 

[Slidlow]

If they could only do welds like KTS did on this titanium rod.

 

[Rôckhewer]

the stress concentration and brittleness associated with welding

Hmmmmmm....
Well... this just in.
THIS.... is an LMI rod ... if memory, and visual recollection serves.
It's installed on my third build (Alembic K Tribute)

That was about what... 6 years ago?
Today?... well.... $#(!!!!... here's yer sign.

So yippee frickin skippy.... I get to pull a board... and replace a rod.

Where do you get them fancy titanium jobbies?

 

[Bruce Johnson]

Well, the big question is: Why did someone break it? Why did someone twist it so tight that they sheared it off? That doesn't look like a fault in the quality of the truss rod. It broke from over-torque.

So, did the neck badly warp or bow? What reason would they have to seriously damage this bass?

 

[Rôckhewer]

Well, the big question is: Why did someone break it? Why did someone twist it so tight that they sheared it off? That doesn't look like a fault in the quality of the truss rod. It broke from over-torque.

So, did the neck badly warp or bow?
(No... I played it a year ago, it was fine)
What reason would they have to seriously damage this bass?

Right?
I basically grilled the (new) owner.
It wasn't that far from.... nominal action.
(I played it a year ago, It was fine)
Didn't the saddles have enough travel to go low enough?... (I thought so)
(Previous owner liked high action)
..."were the strings at pitch when you adjusted?
... etc. ... etc,..
At this point... it is what it is.
Now I gotta fix it.

 

[Slidlow]

Right?
I basically grilled the (new) owner.
It wasn't that far from.... nominal action.
(I played it a year ago, It was fine)
Didn't the saddles have enough travel to go low enough?... (I thought so)
(Previous owner liked high action)
..."were the strings at pitch when you adjusted?
... etc. ... etc,..
At this point... it is what it is.
Now I gotta fix it.

So this guy is the second owner? He bought it from the original purchaser? I would fix it for the original owner but have more trepidation with any subsequent owner.

 

[Gilmourisgod]

Ah geeze, and here I am about to install an LMI rod in a Balance K Build. Evil Omen? Whats all that green crud around the sheared off head? Looks like some kind of corrosion, perchance? I dont know of any manufacturer that offers a six year warranty to a non original owner, I suspect abuse rather than mechanical failure. I assume you are getting well paid for the work, if not, you should be. Kind of like watching a horror movie, but im guessing I'm not the only one who'd be fascinated to see a repair thread on this if you can stand to photograph it. Our condolences, nothing worse than seeing your work trashed.

 

[rudy4444]

Hmmmmmm....
Well... this just in.
THIS.... is an LMI rod ... if memory, and visual recollection serves.
It's installed on my third build (Alembic K Tribute)
View attachment 4144520
That was about what... 6 years ago?
Today?... well.... $#(!!!!... here's yer sign.
View attachment 4144521
So yippee frickin skippy.... I get to pull a board... and replace a rod.

Where do you get them fancy titanium jobbies?

Great photo, and a good example of what can happen if truss rods are installed in a straight through channel with no additional clearance added under the adjustment nut.

I mentioned the reasoning behind that clearance in post #44. As the rod bends the end of the nut can have an extreme amount of force exerted on it's end, and something's gonna give somewhere. Not saying that additional clearance wasn't included here, but it looks to be a straight through channel.

The second point is that it emphasizes the importance of making a rod easily removable and/or replaceable. That requires additional work in the design phase of building an instrument, but it's easier to do that then to pull a fret board. With currently available rod designs like the LMI rod it seems hard to come up with a reason not to make the rod removable.

In any case, sorry for your having to do that work! It speaks highly of you that you would be willing to do the work on an instrument that's been re-sold.

 

[Gilmourisgod]

@rudy4444
How would you make it removable, just keep running the truss rod slot until it "daylights" out the headstock as it pitches downward? I actually thought of doing that on my current build, but it would require a really long TRC. I suppose it wouldnt be too difficult to extend the trussrod slot after the fact if it broke, to provide a path to pull it out. I have cut a 3/8" slot at the head for my 1/4" rod, but only to allow easier access for the hex key. The wider slot gives the hex key more turning space. Are you saying the 3/8" slot should extend the full length of the adjuster head, even if that passes under the nut?

 

[Rôckhewer]

So this guy is the second owner? He bought it from the original purchaser? I would fix it for the original owner but have more trepidation with any subsequent owner.

It ... changed hands, yes. (And appreciated considerably in value doing so).
But the new owner is also highly valued previous client... who has also reordered.
So... It's still "in the family" so to speak.

 

[Rôckhewer]

Ah geeze, and here I am about to install an LMI rod in a Balance K Build

Fluke?...
I found it shocking... and suspected it was over torqued like Bruce said.
Or... I could be at fault?... somewhat?
Because...

good example of what can happen if truss rods are installed in a straight through channel with no additional clearance added under the adjustment nut

It wasn't super tight like rubbing... but no I didn't include significant extra clearance under the nut.

So, did the neck badly warp or bow? What reason would they have to seriously damage this bass?

No warp. I played it a year ago... it was fine then.
Just high action from the previous owners setup.
Maybe he thought it had too much releif... idk.

 

[Rôckhewer]

It wasn't super tight like rubbing... but no I didn't include significant extra clearance under the nut.

Or did I... ??
Look at the round under-cut on the sides of the channel.
I'm pretty sure I ran a drill bit in there to open up around the nut.

 

[rudy4444]

Or did I... ??
Look at the round under-cut on the sides of the channel.
I'm pretty sure I ran a drill bit in there to open up around the nut.View attachment 4144924

Too blurry to tell, but it appears that there might have been clearance.
You don't need any additional clearance at the sides, only the area under the adjustment nut. It can be loose in the channel until it is tightened, that's when the adjustment nut will angle down against the slot and bind up.

That clearance only needs to be under the actual area where the nut is positioned when installed. Unless you experience this it's an easy thing to miss when you are looking for a functional truss rod installation. There have been a few posts in the past detailing this, with folks asking "Why won't my rod adjust? It feels like something is binding..."

If the nut does bind against the channel it may still work but it puts a lot of stress on the threaded portion directly in front of the rod, which is pretty much where your rod failure occurred.

 

[rudy4444]

@rudy4444
How would you make it removable, just keep running the truss rod slot until it "daylights" out the headstock as it pitches downward? I actually thought of doing that on my current build, but it would require a really long TRC. I suppose it wouldnt be too difficult to extend the trussrod slot after the fact if it broke, to provide a path to pull it out. I have cut a 3/8" slot at the head for my 1/4" rod, but only to allow easier access for the hex key. The wider slot gives the hex key more turning space. Are you saying the 3/8" slot should extend the full length of the adjuster head, even if that passes under the nut?

Yes, you can extend the 1/4" wide channel out through the head stock end, as I have shown in this acoustic 6 string photo:

On a bass with a removable neck it could always be withdrawn from the heel end. The channel can then be shorter, not extending all the way up through the head stock. The rod can be blocked into the channel with a small rectangular block glued in the channel. If it needs to be removed it's quick and easy to chisel out the wood and pull the rod out. This works even better on basses that adjust by way of a heel pocket.