Official Luthiers Forum!

Stew Mac has their low profile, 2-way truss rods on sale for under $5.00. Anyone had any problems using these? I have used a few, but no long range experience, and no problems so far.

I’ve been using them since they came out. I’ve probably installed 3 dozen. No problems so far. Using a rounded bit, I can make a perfect pocket for them so there’s no rattle and no need for caulk. When I first used one, I decided that one feature I liked was that they could be removed and replaced without removing the fingerboard (with the neck off, grab it with a visegrip pliers and pull). I’ve never had to do that beyond the first test.

The only thing I don’t like is the size of the captive nut end. On my guitars, I adjust through the soundhole, so the size is no problem. But, on my banjos, there’s not enough wood at the neck end to make me comfortable using these with a peghead adjustment. For the banjos, I use a rod with a smalled adjuster.

I bought a bunch with this sale. The sale makes me wonder if they will be replaced with something else.

I am wondering that myself.

Yes and although the rod has been changed through the years from it's original iteration there have been reports of the low profile rod cracking/splitting the back on the neck.

There are reports of this here on the OLF and in the archives and we had two of them split the back of the neck in our shop too so I have direct experience with this.

I don't know if the dimensions of the rod being more squat than other rods had anything to do with the failures and I am speculating as to causation here so take this with a grain of salt. I don't know if the squatness if that is a word of this rod creates less of a distributed pressure point when it's engaged but we had one blow though a very high end, Luthier guitar selling for big bucks when we were ghost repairing (doing final set-up) for a builder who you all have heard of and some of you know.

Since then we had a second of these also blow out the back of the neck of another luthier built guitar. The first guitar was a Les Paul (60's slim neck) the second was an acoustic. Combined with perhaps three or so reports that I can recall on the OLF of people having these blow out the back of their necks, which by the way is a pretty bad failure to have throwing in question the suitability of any fix or the original neck.... Can you say neck replacement time....

Now can they be made to work safely? Obviously they can and Bob's likely got the ticket to ride on that one and he likely leaves more meat under the channel than the ones we saw fail did. We didn't install them or build the instruments we simply were making nuts, saddles and dialing in a chassis that a luthier built and it split out the back of the neck when turned and not turned very much either we are very careful with the over 20,000 truss rods that we have adjusted by my records.

When I was building I used the best rod I could find and did not care about cost because a truss rod blowing out the back of the neck is not unlike having all four tires blow out at the same time.... it's a catastrophic failure and likely will render the instrument unplayable and perhaps even in need of a new neck.

Wanted to repeat that I don't know if the low profile has anything to do with a less than smooth transition on how the engaged rod pressed on the bottom of the neck channel I think we would need a physicist or mathematician to work that out. So I don't know if this is a design flaw of the rod or builder error in not leaving enough beef under the truss rod channel.

But to your original question do we know of any failures my answer is yes, at least five of them and if you search the OLF you can read about some of them. And I will reiterate that this, the truss rod is not where to get cheap on a valuable component part of your guitar build. The truss rod is super important and will remain super important for the entire life of the instrument (and owner playing it) being necessary with seasonal adjustments, often at first and less so as the instrument seasons and ages.

By the way I had a regime that I put all my truss rods though when I purchased them. I tested them, cycled them, clamped them in a vice and tested the welds on the adjustor. It's that important and it's the place when building to consider being NASA in one's approach.....

I settled on the Blanchard rod and used dozens of them. Nearly 20 years later they still turn like butter and I have not had any failures.

With this said truss rods are never the place to be looking for a financial bargain.

Hesh,
For clarification, I assume that since it blew out the back of the neck, that it was being turned counter clockwise, to add relief. Correct?

Probably in the case of the two that split necks in our shop we were setting relief which for us is usually reducing existing relief. Builders flatten the neck for fret work (hopefully....) and then string tension adds relief and often too much. So I'm not sure but I suspect we were adding relief meaning turning clockwise.

Sorry to be the buzz kill here too I'm not a negative person.

You are not the buzz kill. I was just looking for information. I also am not trying to be negative. I'm just confused, because reducing relief, (clockwise) would seem to be putting downward pressure at the nut and heel, and upward pressure midway down the fret board. Therefore the split would seem to be more likely under the nut, or at the first couple of fret positions, if the split is in the back of the neck.

I just put a low profile Stew Mac in the vice, and turned it 3/4 turn counter clockwise. I did the same one one that came from Blues Creek. They both bent the same amount and in the same curve shape. Nice smooth curves on each, The deflection at the center, after a 3/4 turn from neutral, was 3.5mm on each one. Not sure if this means anything, but I was just curious

Blues Creek has the ones I usually use. I just ordered more of those today. The red one is from StewMac.

Hey buddy I don't see you as trying to be negative either. My hat is off to you for doing some testing on your own that is what most of us do and have had to do to really understand this stuff.

What is missing in your excellent test though is the load. When the rod is confined in a channel it may behave differently than when it's in free space. Remember too it's possible that this rod works fine and that the five examples that I provided all has too little material left under the truss rod. But for me it does call this rod into question AND they redesigned it for a reason....

Now when we describe "reducing relief" it has to be a function of what the neck shape is naturally with no truss rod engaged. So reducing relief on a neck that naturally under string tension, tuned to pitch is flat and straight could be turning it counter clockwise to go into back bow. Conversely a neck that has too much relief naturally under string tension tuned to pitch with the exact same gauge of strings one intends to use will require clockwise adjustment to reduce relief. Or, in other words it's a function of what you have to deal with neck wise in the first place.

This is why I love double action rods and save countless guitars here in Michigan every winter when they are permitted to dry out beyond a point where they can remove undesirable relief or forward bow and hold the desired back shape.

This rod is unique in that its profile is squat compared to other rods. Is there any reason why this "feature" squatness is a better fit in your application?

Stewmac truss rods are problematic and have been well documented online. Friends don't let friends use Stewmac truss rods lol I use Blanchards as well. Amazing truss rods and can be custom made to your specs.

_________________
https://www.instagram.com/fostinoguitars/
https://www.facebook.com/PuraVidaUkuleles/

Please tell us what problems have arisen with the StewMac rods. I did an online search and only found one report of a broken weld. When Martin first started selling this design, I started using those and then went to the StewMac product when the Martin rods started getting hard to obtain. I’ve used the Blanchard rods in my banjos where the adjustment needs to be at the peghead, but I prefer the StewMac design in my guitars because I can install it in a tighter channel so I don’t need caulk to prevent rattles.

If there is really a problem with the StewMac design, I want to know. I don’t want to be selling problems—none so far that I know of.

To me this raises the question…was there something actually wrong with the truss rods, or was there something wrong with the necks?

Edit please see next post.

My mistake JtB and Bob and I apologize to you it was the regular StewMac Hot Rod that blew out the back of necks not the low profile rod. Sheesh I need a vacation.... Anyway it was the regular Hot Rod that wasn't so hot unless you like ventilated necks.

https://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=47897&hilit=+low+profile+

Going to go stifle myself and stand in the corner for an hour....

As Roseanne Roseannadanna used to say, "Never mind."

Thanks for the update. I'm headed for the street, hoping the city hasn't already picked up my trash.

I had one blow out, it was a Hot Rod and I was tightening the rod to reduce relief. Not enough wood under the end of the rod, rod was just too tall.

_________________
Steve Smith
"Music is what feelings sound like"

I had a Stewmac trussrod break as well. Complete garbage

_________________
https://www.instagram.com/fostinoguitars/
https://www.facebook.com/PuraVidaUkuleles/

Hesh, thank you for clearing that up. You had me worried, not so much about the blowout—I understand that—but about some other mode of failure that I wasn’t familiar with.

I used to use the rods supplied by the old Allied Lutherie. They were similar in design to the current Blanchard rods except that the coarse threads were all the way at the end. I had to replace a couple because the threads galled. I didn’t like that and stopped using them. At least the StewMac rods can be replaced without removing the fingerboard (but the neck has to be removed).

Which style rod, and what broke?

After the blowout I went to the Martin 2-way rods and have used them or Blanchards exclusively. I’ve still got a few, not sure what I’ll do when they’re gone.

For the record I load test my rods and have never had a weld failure.

_________________
Steve Smith
"Music is what feelings sound like"

I have not used a standard height Hot Rod style in years. I have used just a few of the low profile ones recently. I used Martin 2-way rods, as long as I could buy them from the Martin website. Then I started using the ones from John at Blues Creek. They are very similar to the Martin rods, at $14.00 each, plus shipping.
I have used 1 Blanchard rod, when I needed a specific size for a Terz that I built. No problems for me on any of the rods I have used. 40 something new builds, and about 50 installed in Harmony Sovereign necks, replacing the 1-way rods that Harmony used in the 1960's.
Here are just a few in the Harmony truss rod graveyard.

I miss her Thanks JTB (and I do remember your name but since you don't use it on the forum I'm honoring that)

Thanks Bob and again I do apologize. I try very hard to be as accurate as possible but I'm getting older and make some mistakes now once in a while. No excuses though.

I used the Blanchard rod on the 45 I have in the wild and never had any issues. The Allied rod did have problems with the adjustor breaking free of the welds. It does look like the Blanchard rod but that is where the similarity ends the Blanchard rod has only had good reports. I think the Blancard rod is stainless too. The reports here of the Allied rod breaking got me in the habit of clamping them in a vice and testing them which is not a bad idea.

Thanks again Bob for letting me off the hook for my error had I been on your end of this thread I would have been very concerned too over my mistake so I am sincerely sorry.

As to the regular, original StewMac 2 way truss rod Hesh is addressing...

viewtopic.php?f=10101&t=56096&p=736142&hilit=rnroberts#p735988

I remember this RN and your excellent, detailed analysis of what happened.

If I had to guess there are at least half a dozen posts like yours (only not as detailed) on the OLF where folks describe the heart break of what can happen or did happen with hot rod truss rods (full size not low profile).

This product was one of the few "whoops" that I've seen from StewMac and even though it can be made to perform fine it is dimensionally such an outlier it invites folks to have this happen to them which sucks.

I just reassembled one of my local wood guitars with a new neck built because of a blowout from a HotRod on the original. Used one from Bitter Creek in the new neck. If I reuse them (got 2), I'll grind off the corners of the brass blocks hopefully to eliminate the stress risers there.