First Project - A rebuild

Take us through building your guitar step by step. Post pictures and tell us what you're doing.
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Keith Reilly
Posts: 54
Joined: Wed Dec 06, 2017 10:58 pm

Re: First Project - A rebuild

Post by Keith Reilly »

Also I need to repair part of the soundboard that got damaged when I removed the top. The spatula dug into the spruce top where it gets covered by the tongue. I guess if your going to damage a soundboard thats the best place to do it. The tear did make it all the way through but on the topside you don't really notice it. You can see a picture of the top in the above post. I was thinking superglue it? Not sure what the best procedure is here. I've seen the suction cup technique and was thinking of going with that.
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tippie53
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Location: Hegins, Pa
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Re: First Project - A rebuild

Post by tippie53 »

any wood glue will work
use plastic cauls once you work glue into it. That area looks like it is under the fret board so nothing too bad
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
Diane Kauffmds
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Joined: Sun Mar 09, 2014 8:13 pm

Re: First Project - A rebuild

Post by Diane Kauffmds »

CA glue (superglue) discolors spruce. Although this is under the fretboard extension, I would get in the habit of using something else when it comes to spruce. The suction cup technique works great. I use titebond, which I water down a bit. But any wood glue will do.
Diane Kauffmann
Country Roads Guitars
countryroadsguitars@gmail.com
Keith Reilly
Posts: 54
Joined: Wed Dec 06, 2017 10:58 pm

Re: First Project - A rebuild

Post by Keith Reilly »

So I removed most of the bracing and plywood cleats. This was a slow going process. Not sure the hamburger flipper is the best for this. I will use a different tool when i go for the last brace and the bridge plate.

I glued up the area under the bridge and the Tail block. I went with the advice and used tight bond for this. This was easy. Also I glued in a new 'brace' at the top of the soundboard. Not sure what its called since its flat, not like the x braces or ladder braces. All guitars seem to have them and I can see it won't get in the way when I put the new x bracing on. I cut a piece of the repair spruce from stew mac to make this. The cold hide glue from tight bond needed heat in order to work. This is what I used to glue this flat brace with. I thought the glue was bad at first, never used it before, but figured it was rubber because it was 34 degrees in the garage and it was something my heat gun could fix. Once it got warmed up it seemed to resemble glue.

I need to rethink how I clamped the brace. I just used weight but it ended up shifting about 1/8th of an inch. Not sure if this is a big deal or not. Doesn't look like the neck block will hit it when I close the top. Also How am i going to get the x bracing on when I get to that stage. Since those won't be flat like this one a weight won't cut it. Maybe I need to make a go bar deck for this?

Also now i'm thinking about how to get the top to have the radius I want. I'm certain there was belly bulge before I took this apart although I never measured this. I hope the new bracing will take any warping out of the top. This looks like a good way to me: http://www.liutaiomottola.com/Tools/BraceArchJig.htm That jig doesn't look to complex and then the sound board will take that shape of the braces. Or so I hope.

After I took the plywood cleats and bottom two braces off that split in the bottom separated some more. I'll see if more humidity will close that up.
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Diane Kauffmds
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Re: First Project - A rebuild

Post by Diane Kauffmds »

This might help with brace names.
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Diane Kauffmann
Country Roads Guitars
countryroadsguitars@gmail.com
Keith Reilly
Posts: 54
Joined: Wed Dec 06, 2017 10:58 pm

Re: First Project - A rebuild

Post by Keith Reilly »

This will be very helpful. Thanks
ruby@magpage.com
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Joined: Thu May 24, 2012 8:03 am
Location: Chestertown Maryland

Re: First Project - A rebuild

Post by ruby@magpage.com »

Keith


Rather than buy or make a brace curve jig, take a 20" string, tie a pencil in one end, and put the other end under a brick. Stretch the string out and use it as a compass to draw a curve on a piece of wood. Cut to the line and sand smooth and fair. Now you have a way to either make yourself a sanding batten or a radius dish, or to draw the curve on a brace piece, then plane and sand that brace to the line.

There are also ways to calculate the Sagitta of curve and draw a small section of the arc you want on your bench without the string:

http://www.liutaiomottola.com/formulae/sag.htm

I don't know why someone in the guitar field has not made up a table of the saggita of various radii, and I have forgotten what I came up with when I made my sanding battens, but it is easy to do.

Then, when you draw the arc, here is a way to avoid the flat ends that you always get when using a batten over 3 points:

flickr dot com/photos/ruby1638/9566635434/in/album-72157635172644427/

The forum strikes again and won't let me put a second URL in, so use your imagination

Scroll to the right and there is text below.

Ed
Ed M
Diane Kauffmds
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Re: First Project - A rebuild

Post by Diane Kauffmds »

What Ed wrote is what I did. You just need room to stretch the string. Since I'm building more, I've taken the time to make or buy the jigs.
Diane Kauffmann
Country Roads Guitars
countryroadsguitars@gmail.com
Keith Reilly
Posts: 54
Joined: Wed Dec 06, 2017 10:58 pm

Re: First Project - A rebuild

Post by Keith Reilly »

I took a hiatus but i'm back on the project. The separation at the bottom of the soundboard got worse so i gave the wood some more humidity with Diane's method which worked well last time. This time it closed right up but not evenly, the two sides weren't level. So I let it dry out and open again and did the same process over again this time the board was sandwiched with magnets to keep them level with one another. This worked nice. Then I glued some small patches of spruce to hopefully keep it together. I guess once my x bracing is in those patches can come out? Not sure if they should be left in or not.
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Keith Reilly
Posts: 54
Joined: Wed Dec 06, 2017 10:58 pm

Re: First Project - A rebuild

Post by Keith Reilly »

I still have the bridge plate and one ladder brace to remove. First the bridge plate. This was rather large and once I was half way through It was rough getting the spatula further along. So I decided to score it and snap it off to where the glue was removed. This worked out nice. once I had a section of the bridge plate off I saw the sound board separating again. So its getting more humidity now and once that is close up I will put in a spruce patch that will hopefully keep the board from separating again.

One thing I also noticed is I cooked my soundboard. I decided to give the bridge plate a little heat. I usually just heat the spatula but I thought that might make things go easier on the spruce top if the glue was already a little warm. But I didn't think about the holes for the strings. The heat was going right down those and burning the top. Don't know what that will do to the sound but at least it will be covered.
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