my questions:
1. Is the non-compression truss rod the same with the Bi-Cut design
2. The link above says that there is the secondary rod in the neck. What's the function of this rod?
3. Is there the secondary rod in all G&L models?
thanx for answer)
Last edited by Craig on Fri Aug 30, 2024 11:58 am, edited 3 times in total.
Reason:Admin fixed link to use Internet Archive path.
I don't completely understand either how the new design works, but I can tell you that there is no secondary rod in the older bi-cut neck design. I want to say the change to the new design happened within the last three years or so, but I'm sure someone here can narrow it down better than that.
[quote="Tim Buffalo Bros"] Personally, I'd like to see some drawings of all the G&L methods as it would help people how they do things from a technical standpoint. I'm not a technical kinda guy, so I hope I explained it correctly!
Here you go Tim. This is actually an ad/flyer that was distributed by G&L in the eighties. Courtesy of Mr. Dale Hyatt.
[quoteNo. First, the site says it was designed by Leo Fender which is an error. The Bi-Cut design was done by George Fullerton and is his patent # 3678795 dated July 25, 1972. It was used on the Musicmans made by CLF Research, and subsequently on the G&L's we all know and love up until around Sept. 2006. The bi-cut used a curved truss rod ~ instead of a non-compression truss rod][/quote]
George's patant #3678795 refers to his 3 bolt with mirco tilt neck attachment that he designed and patented while working for Ernie Ball (Earthwood). This was the design that Leo opted to use at G&L as in his mind it represented the "state of the art" in neck attachment.
Leo's patent #4074606 refers to the flattened truss rod system that was used with the skunk stripe, before the bi-cut was implemented at G&L.
The only patent I could find referring to the bi-cut neck was Chuck Todd's done for peavey, Pat. # 4237944
There could be another pat out there by george or Leo regarding the Bi-cut design, but I can't find it.
I was told that the bi-cut concept had been around Leo's drawing board since the mid 60's but wasn't yet perfected to Leo's liking.
Now here I'm just speculating, I think Leo and George collaborated on a bi cut design similar to Chuck Todd's, the difference in the designs are that Todd's cut was centered on the neck and Leo's cut was offset from center so it could be a bit different from Todds.
If anyone has a pat # for another bi-cut by George or Leo please advise.
Tim, have you had a chance to go through all of George's drawings and blueprints, I have copied the one's posted on the site a while back but would love to look at the rest of them if they are available, very interesting stuff and maybe there are some drawings of the bi-cut in that stack.
The material about the truss rod on the G&L site is mine, so mea culpa on that stuff. I guess it needs some polishing and in general, another stab at explaining the rod.
I can understand how the semantics could lead people to think there are two distinct truss rods, and Tim asking Steve, and Steve giving an answer that seems to contradict the stuff on the site.
At some point I need to get a picture of the thing, but first I'll have another go. The "truss rod" as we think of the integral unit, is one thing. However, there's more to it than that, so follow with me here. There is a cylindrical rod, one end anchored at the heel and other end is threaded for the adjustment bullet at the headstock. That on it's own wouldn't do anything to straighten the neck. The secondary rod is a flat, relatively wide piece that runs alongside the length of the cylindrical rod. The two pieces are welded together at the heel end, and on the headstock end, the flat piece is welded to a sleeve fitted over the cylindrical rod.
As the bullet is turned clockwise, threading down on to the cylindrical piece, the bullet pushes downward on the sleeve. As it does so, the flat rod wants to bow upward against the fingerboard. This upward pressure is what counteracts the string tension and straightens the neck.
So, yes there is one truss rod unit, but it has a passive rod and an active rod. It's not the bi-flex sort where there are two active rods.
We like this rod design because it's intuitive for anyone to use, especially folks used to G&L and Fender types of instruments, it works well, and it goes about its job without compressing the neck longitudinally. It's that longitudinal pressure that often contributes to neck twist, as you can probably imagine that if you squish something porous together hard enough and long enough, it's going to want to deform. In wood, it likes to find the path of least resistance, such as an area with wider grain or grain that's at the greatest angle from the string tension.
Darth Invader wrote:We like this rod design because it's intuitive for anyone to use, especially folks used to G&L and Fender types of instruments, it works well, and it goes about its job without compressing the neck longitudinally. It's that longitudinal pressure that often contributes to neck twist, as you can probably imagine that if you squish something porous together hard enough and long enough, it's going to want to deform. In wood, it likes to find the path of least resistance, such as an area with wider grain or grain that's at the greatest angle from the string tension.
I ask this because it may come up over at BassesByLeo, which has a lot of Tribute traffic: Is the Tribute trussrod like this or more traditional?
When we started the design phase for the Tribute Series, I was discussing the Bi-Cut neck with the factory engineers in Korea. We were looking at doing the bi-cut, or maybe a standard rod either under a skunk stripe or under the fingerboard. I wasn't attracted to the skunk stripe, for one because it would look so different from our USA models. Once we got talking about installing the rod under the fingerboard, they showed me a rod I'd not seen before, the active/passive rod. I thought it was pretty weird, but they were really into the benefits. I was skeptical, but our samples held up well even though I was having trouble conceptually, thinking this pressure on the fingerboard might cause it to split. I guess I had it wrong, but I kept imagining a heavy pressure point right in the middle of the neck. Turns out that pressure is spread much further than I imagined.
Well, the samples kept holding up despite our abuse and we decided to give it a go on the Tribute Series. It was not lost on me that the factory did not want to be supplying us with warranty replacement necks, something the vintage rod - especially with a skunk stripe - gives them headaches with. Here was G&L, not stuck with having to do skunk stripes for the sake of the vintage aesthetic, or any sort of vintage rod for that matter, we were free to do whatever we wanted.
You can imagine that after a while of doing the Tribute Series, we came to the realization that our US instruments would benefit from this design. We had our own ideas on how to do it a bit better, and of course at our place we've got more time, the best CNC equipment, highly skilled people, and a Plek machine to help us dial in the implementation. The data off the Plek, analyzed by our guys as well as Gerd (the Plek inventor) in Germany, proved unequivocably that this design worked better: wider range of adjustment, more consistent bow from end to end, and less twist. We'd already discovered the durability was better, but the Plek data told us the immediate performance benefits, in a neck we designed and made ourselves, were real.
I said "let's do it" and came to you guys to explain why the bi-cut was going away. I expected to get some bumps and scrapes but it wasn't a big ordeal. Sure, there was some lamenting, but it struck me as mild nostalgia offset by an understanding that things can change for the better. I think that it doesn't work that way for FMIC for the most part. Seems to me that despite the fact that we do a fair number of instruments dressed up in '50s and '60s color palettes, G&L players are essentially a progressive sort. If you perceive a change to be for the better, well, then get on with it.
Thanks for asking, Ken. All the best to the lowender crew.
Indeed, despite how it may be worded on the website, that there was an excellent explanation, Dave. Kudos.
Damn, but I gotta get me over to the G&L factory for a tour one of these days. I know it would be dangerous from a GAS perspective, but it's just got to happen soon. Fullerton is calling ...
Tundra wrote:When did the new truss rod get in the guitars?
I believe the change happened in 2005 or 2006. My notes are on my other computer
in San Jose. I won't be returning there until early next week. I will post a correction
if necessary, toward the end of next week.
Information on the innerworkings of the G&L trussrod. This refers to the current, CNC-era, trussrods. My intention is to continue the project with a representative open-air model of a neck so that the trussrod can be seen acting against wood. Soon, I hope.
I managed to piss off my right rotator cuff a few weeks ago, so working in my shop isn't going to happen until I can get full (and safe) movement.
Enjoy!
Ken...
Last edited by Craig on Fri Aug 30, 2024 12:07 pm, edited 1 time in total.
Reason:Admin fixed links
Ken Baker wrote:Information on the innerworkings of the G&L trussrod. This refers to the current, CNC-era, trussrods. My intention is to continue the project with a representative open-air model of a neck so that the trussrod can be seen acting against wood. Soon, I hope.
I managed to piss off my right rotator cuff a few weeks ago, so working in my shop isn't going to happen until I can get full (and safe) movement.
Enjoy!
Ken...
Thanks for the post and the pictorial - Great stuff.
westsideduck wrote:
George's patant #3678795 refers to his 3 bolt with mirco tilt neck attachment that he designed and patented while working for Ernie Ball (Earthwood). This was the design that Leo opted to use at G&L as in his mind it represented the "state of the art" in neck attachment.
Leo's patent #4074606 refers to the flattened truss rod system that was used with the skunk stripe, before the bi-cut was implemented at G&L.
The only patent I could find referring to the bi-cut neck was Chuck Todd's done for peavey, Pat. # 4237944
There could be another pat out there by george or Leo regarding the Bi-cut design, but I can't find it.
I was told that the bi-cut concept had been around Leo's drawing board since the mid 60's but wasn't yet perfected to Leo's liking.
Now here I'm just speculating, I think Leo and George collaborated on a bi cut design similar to Chuck Todd's, the difference in the designs are that Todd's cut was centered on the neck and Leo's cut was offset from center so it could be a bit different from Todds.
If anyone has a pat # for another bi-cut by George or Leo please advise.
Just a little late in replying ....
There are two patents issued to Leo for the Bi-cut neck design. They have been in the Gallery for over five years; here they are: D4528886 and D4670955.
Hope this helps.
Last edited by Craig on Fri Aug 30, 2024 12:08 pm, edited 1 time in total.
Reason:Admin fixed links.
