Official Luthiers Forum!

Owned and operated by Lance Kragenbrink
It is currently Tue Dec 03, 2024 5:46 pm


All times are UTC - 5 hours





Post new topic Reply to topic  [ 12 posts ] 
Author Message
 Post subject:
PostPosted: Tue May 29, 2007 4:49 am 
Offline
Cocobolo
Cocobolo

Joined: Fri Mar 09, 2007 1:40 am
Posts: 134
Location: United States

Oh the joys of building one's first anything...


I think I've messed up my Xbrace. I'm building a dread from the LMI plans and after I put on my xbrace I then pulled out the calipers and measured. Dumb, but that is what I did. 10mm at the center (2mm short of the plan's design. The braces have tapered ends and are curved on the top. I'd show pics, but I'm at work.


I have three thoughts. I could try and remove the brace. I could plane out the brace flat and build it up, or leave it.


So I'm looking for opinions. What would be the consequences of leaving it as is? Less strength?  They seem fairly thick compared to a lot of what I've seen on the forum. I'm just interested in making something that sounds decent and to learn from it, but I do want it to sound decent. I can post pics tonight if someone wants to see them.



Top
 Profile  
 
 Post subject:
PostPosted: Tue May 29, 2007 5:04 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Tue Jan 04, 2005 10:03 am
Posts: 6680
Location: Abbotsford, BC Canada
Jared, are you saying that the brace is 10mm (3/8") HIGH?? If you are talking about them being 10mm wide (which I sort of doubt) than I'd say they are to wide and you could take them down.

That sure is a low brace, for a dread for sure to low. You need the height to ensure the strength of the brace.

Personally, I would remove the braces, make new ones (9/16" high) and put those on.

Laminating a new piece on top would make it stronger, but not as strong as if it were one solid piece. The glue join will see a shear load and will want to separate once loaded. You want that solid piece.

Make it right and you won't regret it.

_________________
My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson


Top
 Profile  
 
 Post subject:
PostPosted: Tue May 29, 2007 5:14 am 
Offline
Cocobolo
Cocobolo

Joined: Fri Mar 09, 2007 1:40 am
Posts: 134
Location: United States

Yes, 10mm high... 8mm wide.


Chisle them out I suppose? Tips? Lets just say it has been a frustrating weekend.



Top
 Profile  
 
 Post subject:
PostPosted: Tue May 29, 2007 5:25 am 
Offline
Koa
Koa
User avatar

Joined: Mon Sep 12, 2005 12:40 am
Posts: 1900
Location: Spokane, Washington
First name: Pat
Last Name: Foster
State: Eastern WA
Focus: Build
Jared,

This is something that most everyone here has experienced or will experience or is it just you and me?

Yup, chisels. Very sharp ones. Work slowly when you get close to the top. Make sure you get rid of the glue on the top, otherwise you won't get a good bond (unless you used hide glue first time around). Spend as much time as needed so you have a clean, smooth surface when you're done, which will get you a good bond for Braces version 2. You don't want the top pulling away from the brace.

It's a setback, but go slow, be careful. You'll be fine.

_________________
now known around here as Pat Foster
_________________
http://www.patfosterguitars.com


Top
 Profile  
 
 Post subject:
PostPosted: Tue May 29, 2007 6:52 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Sat Nov 26, 2005 7:32 pm
Posts: 1969
Location: United States
[QUOTE=Rod True] ......Personally, I would remove the braces, make new ones (9/16" high) and put those on......[/QUOTE]I agree.

[QUOTE=blindreality]

Yes, 10mm high... 8mm wide.


Chisle them out I suppose? Tips? Lets just say it has been a frustrating weekend.

[/QUOTE] You'll be pleasantly surprised how easy they come off with a sharp chisel. (Don't ask me how I know!     )
Be sure to sand/scrape almost all the old glue off. HHG and epoxies are great for re-gluing, but Titebond, AR, and LMI white glues will not bond very strong the second time unless the old glue is removed.

_________________
"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.


Top
 Profile  
 
 Post subject:
PostPosted: Tue May 29, 2007 8:03 am 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Mon Feb 21, 2005 6:16 am
Posts: 2244
Location: United States
First name: michael
Last Name: mcclain
City: pendleton
State: sc
Zip/Postal Code: 29670
Status: Professional
i'm not familiar with the lmi plan but if i read your post correctly you say it only calls for a 12mm high x brace at its intersection? that is low by most standards. what width did it call for?

in any event, 10mm, 3/8", is too low for my taste and i agree with those who recommend removing it and rebracing.



Top
 Profile  
 
 Post subject:
PostPosted: Tue May 29, 2007 10:51 am 
Offline
Koa
Koa

Joined: Thu Dec 01, 2005 5:10 pm
Posts: 778
Location: Madison, WI
what a great jig!

_________________
“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy


Top
 Profile  
 
 Post subject:
PostPosted: Tue May 29, 2007 12:13 pm 
Offline
Koa
Koa
User avatar

Joined: Fri Jan 13, 2006 5:35 pm
Posts: 1021
Location: United States
I want to re-emphasize the point Steve made. Be very careful to remove
all the glue, especially if it is Titebond or LMII's white glue. You want a
really good glue joint for your soundboard bracing.

Best of Luck,
Simon


Top
 Profile  
 
 Post subject:
PostPosted: Wed May 30, 2007 12:49 am 
Offline
Cocobolo
Cocobolo

Joined: Fri Mar 09, 2007 1:40 am
Posts: 134
Location: United States

Well, I gave my chisel and my nerves a good workout last night and removed the xbrace. I got probably 98% of the glue up and along with it more wood than I cared for. There is no discoloration in the path of the xbrace. I did damage some wood, but only a few nicks and a little tear out that came up with some of the glue. Would you recommend putting a little glue in those areas after I get the braces on or just leave it as is.


I read before I started making this thing that it is both frustrating and rewarding. I've found the frustrating side of things.



Top
 Profile  
 
 Post subject:
PostPosted: Wed May 30, 2007 1:25 am 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Mon Feb 21, 2005 6:16 am
Posts: 2244
Location: United States
First name: michael
Last Name: mcclain
City: pendleton
State: sc
Zip/Postal Code: 29670
Status: Professional
wood glues do not provide gap filling strength so filling with glue is relatively useless.

but do try to get all the old glue residue off. try wetting with naphta; it should show up the residue. a small scraper or a sinble edge razor blade with corners rounded an a hook turned works well. the back edge of a sharp chisel also scrapes well.

any glue residue left behind will result in a weaker join.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 12 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 32 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