Interesting Trussrod design

Hambone · #1 02-23-2006, 09:00 PM

I found this on ebay:

http://cgi.ebay.com/VINTAGE-LUTHIER-...QQcmdZViewItem

The design is one that I haven't seen before - twin flat bars that get pulled against each other. Their depth is only 8mm so that's a pretty shallow inlet.

Gives me more ideas

Phil Mastro · #2 02-23-2006, 09:21 PM

Quote:

Originally Posted by Hambone

Gives me more ideas

That is both good and bad.

Weird design, you think it's completely reliable?

Hambone · #3 02-23-2006, 09:59 PM

Quote:

Originally Posted by Phil Mastro

That is both good and bad.

Weird design, you think it's completely reliable?

I don't know why not. The weak link is the TR nut - just like it should be. The brass nut will strip before the steel threads.

FBB Custom · #4 02-23-2006, 10:41 PM

I got a few similar to those from a guy who used to work at Ovation when they imported Warwick. I don't know if that's what Warwick used or not - it might have been from something Ovation made.

They seem okay. I've only used one. I don't know if they can produce the same kind of force that an all-steel rod can.

**Rodent** · #5 02-24-2006, 12:56 AM

what steel threads potentially stripping are you referring to there, Hammy? this auction item is listed as aluminum

I sense a stripped truss rod just waiting to happen. there's a reason that this is a left over from an old guitar shop

All the best,

R

Trevorus · #6 02-24-2006, 01:09 AM

Quote:

Originally Posted by Rodent

what steel threads potentially stripping are you referring to there, Hammy? this auction item is listed as aluminum

I sense a stripped truss rod just waiting to happen. there's a reason that this is a left over from an old guitar shop

All the best,

R

I second that! Al is not good for threads on that higher stress area!

It's bad enough I have to assemble an engine with head bolts into aluminum!

Frank Martin · #7 02-24-2006, 03:48 AM

Quote:

Originally Posted by FBB Custom

I got a few similar to those from a guy who used to work at Ovation when they imported Warwick. I don't know if that's what Warwick used or not - it might have been from something Ovation made.

I don't think Warwick used them. Since 1998, all basses have fixed steel truss rods and steel reinforcement in the neck, according to my repair manual. Might be from Framus Guitars, though, as they are closely affiliated with Warwick.

JP Basses · #8 02-24-2006, 06:20 AM

Those rods were made and used by Warwick indeed. I've had the "pleasure" to deal with them on a couple of old warwicks...

Light and shallow it is, but they were always install so they work backwards and people often ruined the nut by"over thightening"

Peace,
JP

nateo · #9 02-24-2006, 07:20 AM

It's a neat idea, and simple enough for the average garage machinist (though cutting the threads in square stock would be tricky for some). I actually have bezdez in my favourite sellers list just because he/she/it's always selling this kind of stuff.

A bit of figuring and you could probably make it into a serviceable two way rod, too.

-Nate

Hambone · #10 02-24-2006, 08:03 AM

Here's a steel version...

http://cgi.ebay.com/VINTAGE-LUTHIER-...QQcmdZViewItem

There are a bunch of these listed and they all looked the same at first glance. Once I read the steel versions copy, I didn't think to look at the others.

Still think this isn't a good design?

pilotjones · #11 02-24-2006, 11:58 AM

Looks good to me.

andvari7 · #12 02-24-2006, 04:38 PM

But what would the advantages of this design be? Would the flat bottoms interfere with one another, thus preventing the rods from actually doing what they are supposed to? And if not, how can one thread metal that isn't round?

pilotjones · #13 02-24-2006, 10:42 PM

Quote:

Originally Posted by andvari7

But what would the advantages of this design be?

Potentially cheap, easy to fabricate, or light in weight. Plus requiring a shallow rout.

Quote:

Would the flat bottoms interfere with one another, thus preventing the rods from actually doing what they are supposed to?

Possible, but not likely.

Quote:

And if not, how can one thread metal that isn't round?

You put pairs of flats together to make squares, then turn down the ends. For the smooth bars you turn down to the minor thread diameter, minus some clearance; for the threaded bars you turn down to the recommended stock size for the threading die, which you then run down the two of them together. Now you've just made the bars for two truss rods.

I am interested, though, in JP's negative experiences with these.

Hambone · #14 02-25-2006, 11:25 AM

Quote:

Originally Posted by pilotjones

I am interested, though, in JP's negative experiences with these.

If I'm reading him right, he was referring to the aluminum Warwick version. I've heard horror stories about Warwick aluminum trussrods but I didn't ever know their design. I would easily concur that an aluminum version of this wouldn't be good at all.

I'm interested in this since I make my own trussrods. This one in the Walnut Fairlane is like the Warmoth version - rod and bar - but I think I overspec'd it's stiffness and it's only a single action. I've figured out how to easily make it a double action but the design takes a little more work to get it installed correctly. I would rather just rout a very simple channel for installation and this design would only require a flat bottomed channel - the simplest to cut.

Suburban · #15 02-28-2006, 04:20 AM

Darkness - darkness - whoever let Voldemort into my firewall?

I can't get access to e-bay any more (or to photobucket and similar...yuck!)
Can somebody mercyfully copy a pic or two into this thread? I'm nearly fainting from curiosity

pilotjones · #16 02-28-2006, 08:40 AM

Quote:

Originally Posted by Suburban

Darkness - darkness - whoever let Voldemort into my firewall?

I can't get access to e-bay any more (or to photobucket and similar...yuck!)
Can somebody mercyfully copy a pic or two into this thread? I'm nearly fainting from curiosity

Hope this works for you:

pilotjones · #17 02-28-2006, 12:49 PM

BTW Hammy- did you get my PM re: aluminum disks?

warwickben · #18 02-28-2006, 03:27 PM

sorry if this doesnt add much but ive never seen a truss rod like that befor.

Hambone · #19 02-28-2006, 03:45 PM

Quote:

Originally Posted by pilotjones

BTW Hammy- did you get my PM re: aluminum disks?

Yes, got it and am acting on it now!

paintandsk8 · #20 02-28-2006, 09:16 PM

Do you think there would be a significant chance of buzz when you didn't have much tension on the rod? I would probably want to come up with some type of thin insulating material between the rods just to be safe. As others have said, I like the simplicity of this design, looks like something I could have the guys at the machine shop throw together pretty quickly in custom lengths. How 'bout the nuts though, is that style nut readily available?