I'd be interested for that kind of coin.

Now - the big question. What about twist? How can we correct that without using traditional heat pressing?

Hi Stuart,
I been mulling over embedding a honeycomb panel of carbon and nomex about about 1-3/8 wide (or so) x 1/4 thick just under and slightly into the fingerboard and into the neck shaft. Haven't done though as I'm afraid it might be too stiff and have a negative effect. I'd be interested in you thoughts.
Your truss rods look good btw.

I think what you might be doing is holding something and looking for a purpose. Ask yourself what problem it solves. If you don't have a clean answer it ends up a waste in the end. Unless you make it and find out. Then you'll know.
...

I totally agree with this, I'm not sure what if anything it brings to the table. There's a billion guitars out there that work just fine without it.
This is ultimately why I have done it yet.

Thats really cool Stuart.

Sorry about your wife man

Hi Stuart,

Can you comment on the strength of carbon fiber in terms of shearing -- ie would a careless customer have a much easier time damaging this rod than say the Blanchard rod? Also, what do you think about using carbon fiber bolts in a guitar - are they strong enough? we aren't talking that much weight savings for the bolts but the truss-rod would definitely have an effect.

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Simon

One thing I will add to this conversation in regards to how important truss rods are... I was using the Martin rods for a while then found them difficult to get and switched to the Bitterroot rods which are very Martin like. What I like about those rods is that you can design your neck such that the rod is removable. Even the very best of the very best has a failure rate. So if a rod fails and you can simply remove it and replace it that's good design imho.

I expect that the titanium stretching (or the threads distorting) is the weak point in this design but honestly I wouldn't know how to even make that comparison, i'm 100% not an engineer Weight is about 55-ish grams for a 14 fret rod, and the weight is off center, with the excess by the nut. I use it with the nut in the neck block and the headstock end of the neck is very light, which was my goal.

When I use them I am also embedding them within a carbon fiber U bar. The neck is nice and stiff, I have never actually needed to use the truss rod. but it is there!

47 grams is amazing for a double acting truss rod. For those high end builders who value light weight necks, $65 would probably be acceptable. I hope that rod finds its way to market at some point.

Just to clarify the weight issue on the stainless rods that I make, a 13" rod (12 fret) weighs 96 grams and a 14 1/4" (14 fret) rod weighs 104 grams. I recently started making the backbone of the rod and the end blocks out of a single piece of stainless bar, thereby eliminating the silver brazing joints at each end of the rod. I'm also milling the backbone into a "T" shape to reduce weight.

I'm really happy to see various people giving truss rod design some serious attention. A truss rod is a VERY important piece of hardware in a guitar. Rods that are ineffective or fail in use are a real disaster !!

Mark

It wouldn't be too hard to compare the thread loading ability of the titanium if one knew the exact alloy. A lot of truss rods are made from simple 1080 steel...and some are made from unidentifiable alloys. The mechanical properties of the materials are all published. The property "sheer modulus" would basically cover the load on threads. You want to compare the other properties too...but sheer modulus is the first property for thread loading. Yield strength would be the next property to consider.

Basic, generic "titanium" Titanium Ti-6Al-4V (Grade 5), Annealed is about half the sheer strength of 1080 steel....so....I guess I'd worry when it comes to applying moderate torque.

Thanks Stuart- I am using grade 5, and looking through the charts it certainly doesn't seem to be as ideal a choice as pretty much any form of steel. I can _kind of_ understand those numbers- elasticity, elongation and deformation- Where I really lose it is trying to calculate what kind of force we are actually talking about inside the neck when the screw begins to turn. I can imagine some of the variables (or at least I think I can) but have no idea how to come up with a number. Titanium is more likely to deform than steel, and more stretchy, yes- but it still might work? Or could be designed in a way that could be made to work and still be lightweight?

I felt OK about it because others were making titanium rods (never the best rationalization), I didn't expect to really need it in my necks, and my initial "tests" seemed promising. But there's no long term data test under pressure. I need to find someone to help me see the whole picture.