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Can someone explain the science of CA (Superglue) and guitar building materials? I was trying my first attempt at wood binding and purfling and about shot myself trying CA glue. The first tiny strip of WBW purfling went on great and I was surprised at how easy that was, then while trial fitting, the wood binding stuck too, and I thought hmmm I've heard of people using CA glue for wood binding so I start to flood the tight joints and so far so good but one section will NOT stay stuck.

I'll clamp it. Unstuck. More glue? Nah that's not it. Should it be used on wood at all? Perhaps the gap filling type. No go. Seems no matter what I try it will NOT stick in this particlar section. Then I notice another small gap. OK I'll reglue, and again not a chance. But other areas are glued forever.

Sigh.....I don't understand this glue and its nature and true aplications for guitar building. So frustrating at this point, had to leave the shop before I broke something. Oh and of course I have no fingerprints left as the skin IS stuck permantly to the binding.

Thanks in advance

Larry

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Larry, What is most likely happening is that you have too big a gap between the binding and the channel. CA glue works great for wood binding, or at least it does on the woods that I have tried, but it will fail if the binding is not really in contact with the channel. Your binding probably need to be fitted better. With even a hairline gap, CA glue will not work at all.

I have, however, filled gaps with CA glue. When it hardens, it can be sanded level and in some case is nearly invisible. That section of glue is not holding the binding on, however.

Is there a chance that CA will sink under laquer like white glues does?

Ive also had problems with CA not sticking, but time fixes that, as long as you clamp up up so the pieces dont move.

[sermon] The bindings have to be absolutely TIGHT for the CA method to work. I know it is a pain to get rid of all the gaps on wood binding, but there is really no short cut here. You would be heartbroken if they open up on you after finishing... so you might as well take the time to get a good fine now. [/sermon]

with that said... something else you need to remember with CA is a tiny drop goes a really long way - don't flood the joint.. think of it as spot welding it in place and then just keep tacking places you have not glued yet. It really works well, but there are a few minor gotchas to watch out for.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

CA is an acrylic monomer: tine molecules that can link up to form something like plexiglas. They are kept from reacting in the bottle by a bit of acid in the mix. When the glue hits a surface there is usually enough water to dilute the acid enough for it to start kicking over, and once it starts it keeps going.

Many woods have a lot of acid in them. CA cures slowly, if at all, on things like walnut and koa, and even maple can slow it down sometimes. A small amount of an alkaline, such as baking soda, or some borax or ammonia, can help it to 'kick'.

Once the stuff does kick over on a surface there may be no alkali left to help start the next batch. The second shot will often just sit there and look at you all day without curing. Until you touch it, that is....

[QUOTE=Alan Carruth] CA is an acrylic monomer: tine molecules that can link up to form something like plexiglas. They are kept from reacting in the bottle by a bit of acid in the mix. When the glue hits a surface there is usually enough water to dilute the acid enough for it to start kicking over, and once it starts it keeps going.

Many woods have a lot of acid in them. CA cures slowly, if at all, on things like walnut and koa, and even maple can slow it down sometimes. A small amount of an alkaline, such as baking soda, or some borax or ammonia, can help it to 'kick'.

Once the stuff does kick over on a surface there may be no alkali left to help start the next batch. The second shot will often just sit there and look at you all day without curing. Until you touch it, that is.... [/QUOTE]

VERY informative Alan. I'm gluing Koa and that matches my experience exactly. I might think about a 'kicker'. Have you ever mixed your own?

Thanks Again

Larry

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Thank You and Best To All

Larry, do you know that you can by an accelorator? You could spray the accelorator over the area first, than install the binding and apply the CA. That would help set the glue realy fast.

I tend to dry fit the entire binding job, tape around the edges than glue. Leave for some time (read 1 hr or more) than get to scrapping the tape and glue. Just don't use much, like Brock said, a little goes along way.

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"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

I have found that simply breathing on the area will speed up the process when CA is reluctant to dry. Guess there has to be some benefit to having a caustic personality. Might not work as well for the sweet tempered among you!

When Breathing or blowing over CA, remember to try not to inhale it's fumes.

Also, I had recently heard that there is a life expentancy for CA, in other words the joint could fail in 15 years or so. Has anyone else heard or experienced that?

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Tickle your guitar daily, and it'll tickle you back.

John,

That statement does exist in the MIMF archives. I found it there while perusing their voluminous information bank one time & posted the information here - strictly as a "look what this guy said" kind of thing. It has been neither supported nor refuted by any evidence I've seen posted by others or by my "Googling" the subject. I don't think it's very likely, given the widespread, long-term use of the stuff, but the possibility does exist I guess. It would be reassuring to know for certain.

Skip

Hey, this guys still hanging around. I seem to remember this commercial about 25 years ago (1973 actually).

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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

Speaking of CA and questions about it's long-term holding power, I'm going to post a new topic about using CA to glue bridges. On second thought, I'll search the archives first, and then post my question if it's not already answered.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

[QUOTE=Rod True] Larry, do you know that you can by an accelorator? You could spray the accelorator over the area first, than install the binding and apply the CA. That would help set the glue realy fast.[/QUOTE]

Yeah I found a hobby store nearby I'll pick some up today.

Larry

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Thank You and Best To All

Warrnig on the use of CA accelarants. They can cause the CA to craze and be brittle. I dont recamend the use of accelerants in any lutherie process.

If installing plastic bindings (UUCK ) I use Duco if wood I use either Hide or Tightbond.