Official Luthiers Forum!

Owned and operated by Lance Kragenbrink
It is currently Tue Apr 16, 2024 5:23 pm


All times are UTC - 5 hours





Post new topic Reply to topic  [ 9 posts ] 
Author Message
 Post subject: Truss rod breakage?
PostPosted: Tue Jun 23, 2020 5:49 pm 
Offline
Walnut
Walnut

Joined: Wed Feb 21, 2018 1:43 pm
Posts: 10
Focus: Repair
Status: Amateur
Hi guys,
did I screw up my truss rod, or do these things naturally come off if you turn'em too far?

Have a look at the pics. I was going to loosen the TR to get a bit more relief, when it suddenly cracked. Either it was just gummed up and broke loose with a loud bang, or it literally broke. It didn't fall out on its own, I took it out to have a look, however it felt like the threads were still working. But I can't tell if this is normal or broken. Anyway, I'm having a hard time getting it back in, so either way, this is not nice!

Luckily it isn't an expensive guitar, so I might just use the opportunity to remove the fret board and replace the TR. Can't be that hard.

Any ideas?

Thanks! :)


You do not have the required permissions to view the files attached to this post.


Top
 Profile  
 
 Post subject: Re: Truss rod breakage?
PostPosted: Wed Jun 24, 2020 10:10 am 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Thu Nov 04, 2010 1:46 pm
Posts: 2124
First name: Freeman
Last Name: Keller
Focus: Build
Status: Amateur
Sorry, I can't tell. What kind of guitar is it? Single acting rods usually have a nut that is threaded on and will back off. Single acting rods will break, usually when you are tightening them. Double acting rods have the nut welded to the end of the rod but I've honestly never heard of one breaking. The old Martin style square channel single acting rod kind of looks like that, the nut is welded on and could probably break.

Removing the fretboard and replacing the truss rod is not trivial. Best to remove the neck from the guitar but it can be done with it on. Heat the f/b with a silicon blanket, work pallet knifes between the f/b and neck. Figure out what kind of t/r you really have and build or buy one like it (premade rods differ quite a bit in size, shape, how they work and the channel required. Glue the f/b back on, level the frets and fix the finish. Not too hard


Top
 Profile  
 
 Post subject: Re: Truss rod breakage?
PostPosted: Wed Jun 24, 2020 11:08 am 
Offline
Koa
Koa

Joined: Fri Feb 10, 2017 11:09 pm
Posts: 870
Location: Cowichan Valley, BC, Canada
First name: Conor
Last Name: Searl
City: Duncan
State: British Columbia
Zip/Postal Code: V9L 2E5
Country: Canada
Status: Semi-pro
I can't tell from your second picture if that's a broken weld, or just the threaded end of the nut. I've unscrewed the ends of truss rod nuts and had them out looking like that though. I wonder if it is an inexpensive guitar perhaps the crack you heard was the truss rod breaking away from glue in the channel?

I think you might be able to screw it back on if you can get it back into the channel.


Top
 Profile  
 
 Post subject: Re: Truss rod breakage?
PostPosted: Thu Jun 25, 2020 7:21 pm 
Offline
Walnut
Walnut

Joined: Wed Feb 21, 2018 1:43 pm
Posts: 10
Focus: Repair
Status: Amateur
Hi guys, thanks for your input.
The guitar is a Dobro Hound Dog which to my knowledge is Epiphone-made nowadays. Correct me, if I'm wrong.
Weird though that I wasn't able to find any detailed information on this guitar, as one would assume, that Epiphone might at least mention these guitars on their web site. Couldn't find anything.
So if anybody knows a little more about these guitars, bring it on.
I got it used for a good price, so I'm not panicking right now.

Obviously I can't tell, what kind of TR is used in this guitar, but what you (Freeman) said about single action truss rods seems to be the case here.
And yes, Conor, it doesn't look like a broken weld, I do believe (and hope) that the crack was the truss rod breaking away from the glue.

Now there's another problem: I tried to put the nut back in, but apparently there was some sort of sleeve around the nut, maybe heat-shrink tubing, which now makes it hard to get the nut back in. I will have to try and remove it with a small knife or a very narrow chisel, as this thing always gets in the way when I'm trying to insert the nut. It's some sort of soft-ish flexible material, which bends inwards and blocks the access.
Has anyone seen something like this?

I'm still confident that I'll get it fixed, and I will have learned something from it. We'll see.
Do keep your thoughts coming though :)


Top
 Profile  
 
 Post subject: Re: Truss rod breakage?
PostPosted: Thu Jun 25, 2020 9:00 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Thu Nov 04, 2010 1:46 pm
Posts: 2124
First name: Freeman
Last Name: Keller
Focus: Build
Status: Amateur
OK, the Hound Dog was a spider bridge resonator that I believe Dobro had made in China (or PacRim somewhere). If I remember my Dobro lore, the body as made overseas but it got an American spun cone and set up. Dobro as a company has gone thru all sorts of ups and downs and buyouts - during the 1980's they were bought by OMG or someone (I'm going from memory, all this is documented and actually makes for fascinating reading. OMC owned Gibson for a while and of course Gibson bought Epi so there are some connections. I think the Hound Dog was considered a good economical spider bridge, particularly if it has a US cone (Quarterman or Beard)

Second, I am a bit of a resonator fan - I have a 1932 Dobro model 27, a 1980 Duolian and a wooden tri cone that I built myself. The 32 does not have a truss rod, the 80 has a single acting rod with the adjuster in the head (and mine has a double acting rod but thats neither here nor there).

There are some significant differences when working on a resonator as opposed to "normal" guitars. Depending on how you intend to play it there are several different things to think about - so that will be my first question - is it round or square neck? How do you plan to play it (lap, Spanish, slide, fretted, mix of slide and fretted)? What is the relief right now (and the other setup parameters?

Two fairly important things - first the neck comes off pretty easily if you know the secret. If it is built like a traditional resonator it will have a neck stick that extends into the body and is anchored either at the sound well or at the end block. Like a banjo, the neck stick is how you set the action. It also means that if you decide to work on the fretboard the neck will come off pretty easily. The second is that normally the fretboards on lap style resonators are flat or have very slight radius Also, of course, if you are planning to play strictly lap style relief is meaningless since your strings will never touch the frets.

So before you go too much farther answer those questions and I'll have a better idea of how to help


Last edited by Freeman on Fri Jun 26, 2020 10:20 am, edited 1 time in total.

Top
 Profile  
 
 Post subject: Re: Truss rod breakage?
PostPosted: Fri Jun 26, 2020 8:24 am 
Offline
Contributing Member
Contributing Member

Joined: Sun Feb 17, 2013 4:58 pm
Posts: 1449
First name: Ed
Last Name: Minch
City: Chestertown
State: MD
Zip/Postal Code: 21620
Country: United States
Focus: Build
Status: Amateur
Before the fretboard is removed, is it a good idea to take off the first and say the 12th fret, drill a say 1/16" hole through the slot off center and into the neck 1/8" or so, then remove the board? When replacing the board, tap a small say 17 gauge brad into each of the holes in the neck, nip off the heads so they are sticking about 1/16" above the fretboard, then snap the fretboard onto them and it will be in its original spot and not swim around when gluing.

Ed


Top
 Profile  
 
 Post subject: Re: Truss rod breakage?
PostPosted: Fri Jun 26, 2020 11:18 am 
Offline
Koa
Koa

Joined: Fri Feb 10, 2017 11:09 pm
Posts: 870
Location: Cowichan Valley, BC, Canada
First name: Conor
Last Name: Searl
City: Duncan
State: British Columbia
Zip/Postal Code: V9L 2E5
Country: Canada
Status: Semi-pro
I would assume that sleeve is likely some sort of wrap to keep the truss rods moving parts clean and clear of glue, and to mitigate rattling around in the channel.


Top
 Profile  
 
 Post subject: Re: Truss rod breakage?
PostPosted: Sun Jun 28, 2020 5:04 pm 
Offline
Walnut
Walnut

Joined: Wed Feb 21, 2018 1:43 pm
Posts: 10
Focus: Repair
Status: Amateur
Hi there again, thanks for all your valuable information!
So I managed to remove this strange black plastik sleeve, that kept m from inserting the nut back into the cavity. Now it worked, and I was able to get the threads to grab again. Seems like the TR is indeed fine, and the loud crack came from it breaking loose. Still, one thing puzzles me: The action seems to be even lower now, as in it's having a slight back bow now, even with the TR fully loosened. It doesn't fret out hough. Doesn't make sense.
I'm going to set it up for slide mainly, so i wouldn't kind a little more relief. The string pull alone doesn't seem to be strong enough to bend the neck forwards (It's a set of gauge 13-56 steel strings) I might use even heavier ones, we'll see.
BTW it's a round neck.

I ordered a new wood insert for the spider bridge, which I can shape to my liking. The current one is low, which is fine for normal playing, but it's also rounded, which makes the high e string sit even lover than the other strings above the fretboard. I keep fretting the string out when using the slide. So I was thinking to leave the new insert fairly straight ad a little higher, to get the action up.

As for the neck joint, I can't confirm that there's a neck stick inside the body, doesn't look like it. The neck seems to be glued to the body like any guitar. The finish at the neck joint also seems seamless, I doubt the neck can be taken of easily. But since I won't have to remove the fretboard now, it doesn't really matter.
When the new insert has arrived, I'm sure I'll be able to set it up the way I like it.

In the meantime, thanks again for your help, stay safe and healthy, folks!


Top
 Profile  
 
 Post subject: Re: Truss rod breakage?
PostPosted: Sun Jun 28, 2020 7:19 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Thu Nov 04, 2010 1:46 pm
Posts: 2124
First name: Freeman
Last Name: Keller
Focus: Build
Status: Amateur
Glad you got the truss rod worked out. You haven't presented any measurements so I really can't comment on your set up. A roundie can be played either as a lap guitar (with a high nut or extender) or Spanish style - in that case the action is pretty much up to you.

I have my old 1932 Dobro set up for lap style play - 3/8 action right down the neck, relief doesn't matter, strings as flat as I can get them. My biscuit and my tricone are set up for slide plus fretted play - action is a hair higher than I would set a pure fingerstyle guitar (but then I play slide on all my guitars). I would say 15 to 18 thou at the first fret, 70 to 90 at 12, 4 or 5 thou of relief. I build my guitars with 20 inch radius fretboards so that is the radius of the saddle (expect the lap guitar). You only have limited space under the palm reset so most of the time people will center their strings in the opening and then adjust the neck angle. String height at the bridge also affects the break angle.

Here are the neck sticks in the 1932 Type 27

Attachment:
IMG_2406.JPG


It extends to the forward part of the cone ring and is screwed to it

In both cases the necks are not glued in but there are a couple of screws under dots on the upper fretboard. Hound Dog might be different, I've never worked on on.

String choices are up to you but depend a bit on tunings. The sets sold as "resonator" sets are generally design for so called "dobro" or "high G" tuning which is different from open G. For open G or D I prefer mediums with a thicker first string - 14 or 15. Some folks like an unwound third. If you plan to tune up to A or E consider some lighter gauge strings.

Intonation can be a crap shoot on a resonator. Many of the old ones have no precompensation - the saddle is at the scale. That is fine if you are playing slide, you've got a pretty good intonator on your pinkie. Its not so good for playing fretted. I try to push the break point as far back as I can get it but since I'm not playing fretted stuff way up the neck it turns out to not be a great problem.

Last thing on setting up a spider - the little tension screw in the center of the cone should not be too tight - it can choke the cone. As I recall I snugged mine up, then gave it about a half turn. Oh, and spend some time hunting down rattles - resonators can be full of them (a piece of foam under the tailpiece can eliminate quite a few)

Good luck, have fun, ping me if you have any questions

Here is the 1980 Duolian, the neck stick extends all the way to the butt of the guitar like a banjo


You do not have the required permissions to view the files attached to this post.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 9 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 11 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
phpBB customization services by 2by2host.com