Titanium rods for weight reduction.

[Ken Byng]

I have been carrying out a program of replacing the push and pull rods on my Emmons. Stainless steel rod going, and being replaced with 3/16" titanium rod. Certainly lighter and stronger. When this project is completed, I will start on my Zum next.

[Will C]

I wondered about that stuff myself - but isn't it very expensive? Wonder how hard it is to put a thread on the end.

you beat me to it, Will. How hard is it to thread, or bend the end over, Ken? enquiring engineer-like minds want to know...!

[Ken Byng]

Easy as stainless to bend and I have just cut a thread on a piece of scrap. Again very straight forward.

On my Emmons I just have to flatten about a centimeter of the rod end a bit so that I can drill a hole for the raise hooks. It's a doddle.

[Zumbilly(Murdoch)]

Hi Ken, Curiosity and laziness to research prompts Me to ask, What will the weight difference be after a full change and what would the rough cost be per rod or batch?
Whilst titanium may be stronger than steel I have never yet heard of a rod breaking.
Best regards
Billy

[Will C]

Not strictly on topic, but related: I was speaking to a tech guru at a 3D printing exhibition recently and he got interested in my idea of replacing all the bellcranks with 3D printed plastic parts - yes, choose the plastic stock with care for the right mechanical and fatigue etc characteristics, but on a quick calculation it could save about 6lb over T6061 alloy parts based on the number in a typical modern steel. It's surprising how the weight accumulates even when using light alloy. And the laminar method of laying-down the plastic part can be arranged to orientate the maximum strength along the planes where it is most needed.

[Paul Brennan]

Any ideas on how replacing metal bell-cranks, rods, linkages, etc with plastic equivalents would effect the tone of the instrument?

[Ken Byng]

Hi Ken, Curiosity and laziness to research prompts Me to ask, What will the weight difference be after a full change and what would the rough cost be per rod or batch?
Whilst titanium may be stronger than steel I have never yet heard of a rod breaking.
Best regards
Billy

Hi Billy
I'm not sure yet what the overall weight gain will be, but I am sure that the titanium rods are at least 50% lighter than the stainless ones. The cost for me to re-rod my Emmons will work out somewhere between £60 and £70.

Re the potential use of 3D printed parts, I thought about getting some pullers made for my Zum, but then discounted that idea as I thought that the tone could be affected. Having a form of plastic in the pulling chain (in addition to the nylon tuners) was too much of a gamble. Paul - replacing the parts that you have listed with plastic equivalents would definitely affect the tone a great deal IMHO.

[Will C]

Paul Brennan asks what effect it might have on the tone or sound if one replaces some parts with plastic - e.g. bellcranks.

My instinct is to say I don't expect it to have an effect, because the bellcranks are not directly part of the major tone contributors: the cabinet, the neck, the changer and its mounting, the headstock and mounting (which all relate directly to communicating the string vibrations) together with the pickup and its positioning.

But they are I think part of the "peripheral scenery" in terms of vibration, so who knows? I'd still put money on you not being able to hear a difference.

Ken says it will - some brave soul will have to try it and see!

[Ken Byng]

Paul Brennan asks what effect it might have on the tone or sound if one replaces some parts with plastic - e.g. bellcranks.

My instinct is to say I don't expect it to have an effect, because the bellcranks are not directly part of the major tone contributors: the cabinet, the neck, the changer and its mounting, the headstock and mounting (which all relate directly to communicating the string vibrations) together with the pickup and its positioning.

But they are I think part of the "peripheral scenery" in terms of vibration, so who knows? I'd still put money on you not being able to hear a difference.

Ken says it will - some brave soul will have to try it and see!

The only reason why I said that is because my best sounding guitars have round cross shafts where there is maximum contact with the pullers or bell cranks that have a very tight fit with the cross shafts. That says to me that the pullers play a significant part in the tone. My view is only an opinion and is not scientifically proved in any way.

As you say Will, the only way to ascertain whether 3D printed pullers can equal metal in the tone stakes is to try it. Certainly my polymer bar made by Basil has an effect on tone, but in a pleasing way to my ears. If the printed pullers show no sign of basic tone deterioration then that could be an answer to the prayers of folks who need a supply of these parts for their guitar(s).