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I am sure that has been gone over before but I could not find much. I thought CA glue might stand for Catalyzed Acetone. At any rate I have a repair that has hairline fractures though the peg board. From what I have seen and read CA glue is thin viscose glue that will seep into these hair line fractures, and then clamp. If you ask for pictures, I spent a whole night trying and I could not post them.
Thanks in advance for your 411.

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".

Cyano Acrylate glue ... or crazy glue for the uninformed masses ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

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Old growth, shmold growth!

If applied to wick into hairline fractures can you scrape over flow off? Would a scalpel work to separate the excess glue from the surface. How do you gauge how much glue to apply and how do you know it has permeated thornily through the fracture. It would be very unpleasant to get the finish done and find your repair was unsuccessful. I know these are a lot of questions. I have found what the glue is but proper usage is another animal. If some one could enlighten me.

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".

CA is available in different viscosities; the thinner stuff really wicks into tight spots. the dried stuff does not really "scrape" off, it is very hard and verymuch bonded to the wood. it prettymuch needs to be sanded off, or dissolved with acetone, which could lead to other problems. so if you don't plan on sanding, i would try to avoid overflow.
a great thing about cyanoacrylate is that it dries very stiff and light. i have brushed it on to small pieces of soft wood just to make it stiff and durable. it really discolors light wood though, sort of makes it translucent where it seeps in. so beware of that. as far as guitars go, i think with rosewood and ebony fretboards/ and inlaying/fret markers it really is unbeatable.
i am by no means a pro, this is just what i know/believe/experience.

i am by no means a pro, this is just what i know/believe/experience.

I will take the knowledge of experience any time. With screw-ups you gain a real appreciation of experience.

Thank You all.

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".

Hmmm...Rather dubious results. The hair line fractures did not wick the runny CA in. I even tried a 23 gauge needle to reduce overflow and shoot/ inject right into the hairline fracture. I stressed the fracture to see if I could open it more so it would receive the Thinned down CA better. Hmmmm....I have a wicked mess to clean up before I try again.
This is becoming an excellent opportunity to improve my sense of humor...

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".

You have the right attitude for sure Joe. If you have the thin CA and there is in fact a crack, it should wick in. There are at least 4 different viscositys of the stuff. There's a thing called a pipette that makes a very good applicator.

Good Luck,
Danny

Priming with denatured alcohol can work well, especially on difficult to clean breaks.
Fresh, water-thin CA is a must for this kind of repair. I find that scraping works well
for cleanup, assuming a sharp edge and taking care with the transition.

+1, with emphasis on 'clear', 'fresh' and 'water thin'.

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Jim Hansen

Practice makes perfect with this stuff, and I find it works best with dark colored woods. It will wick into and discolor spruce tops.

Get a package of razor blades (they make excellent scrapers for dried CA) I also use accelerant - one light spray will harden the CA. Then carefully scrape the overflow. Repeat the process. I've found I had to use the slightly thicker viscosity on some fissures or cracks (like in the binding) because it was wicking too effectively.

I dont know what challenges you had posting pictures, but I need to drastically reduce the size of any of my pictures before I can post. Using the plain old "paint" application in windows works - I reduce the size to about 15% of actual and that usually gets the picture size below 100K.

I find scotch tape works well placed right along the crack on either side to help with clean up. Tape it up real good because the runny stuff will get every where. I use a curved glue removal chisel to chisel it real close to the finish then follow with a wet sanding.

Course the other question is, are you just looking at finish cracks? If you cannot massage the crack open then maybe it needs no repair.

OK I finally got some photos uploaded to photo bucket.
This is the guild d12d I am fixing; the head was shattered from about a 10' fall from the stage. All of the damage is above the scarf joint. I was debating taking it apart at the scarf joint and fabricating a new head. With all of the pieces I had to glue back together I was not sure, and am still not confident in the repairs.
http://s1198.photobucket.com/albums/aa4 ... G_2913.jpg
http://s1198.photobucket.com/albums/aa4 ... G_2916.jpg
http://s1198.photobucket.com/albums/aa4 ... G_2914.jpg
http://s1198.photobucket.com/albums/aa4 ... G_2914.jpg

I think I got the CA to wick in, now I need to work on the cosmetic repairs. That looks like it will be a problem also as the scarf joint has two dif. colors of wood. I was thinking about doing the head lacquer black with an after market decal....Any Ideas...???? The owner is OK with the black head w/ Abalone inlay border 3/32' wide.

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".

At least one of those fractures is going across the head and appear to maybe go through it. This is chancy for a glue repair. If you have enough surface area for gluing and can get the glue through, then you could be successful, kind of like a finger joint.

Scraping should work, OK. A file works, as does sandpaper. If you use sandpaper ensure that you use a firm backing block otherwise you risk sanding the wood faster than the glue.

The scarph joint should look like that. The head shows the face of the wood while the other part is more like end grain because it is showing the neck cut at an angle.

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Joe you need a new headplate and a backstrap overlay if you want the repair to last. Check out Frank Ford's site http://www.frets.com/FRETSPages/Luthier/Technique/Structural/BrokenHeadstocks/BackstrapOverlay/phoverlay.html

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

See that is what makes me uneasy about this repair Doug. The crack does look like it goes across the head so without an X-ray I have to assume the worst. Being that it is above the bottom 6 machine heads it will have aprox. 180lbs of torque on it.

Hey Todd,
I used one of my insulin syringes to apply the super glue (extra runny). Then Used the blue tape on my straight edge razor blade. Then I wrapped some 600 wet/dry around a pen blank of purple hart to smooth it out.

Ken I think you are thinking along the same lines I am. That is the only way I will feel good about the repair. Right now I am not feeling " good job Joe"; It feels like I took a short cut. I was riding the fence and waffling but I think I am going to step back, start again and go with the back plate idea. Then I can feel good about the repair. BTW, frets.com has some good stuff don't they?

Thank you everyone who has advised me. I will post pics when the repair is done unless you would like to see the progression.

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".