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Here is a strange one..i was going to fill in a couple gaps I have between the binding and back, they are both IRW with no purfling.

So i grab a sheet of paper, sand a small pile of rw dust, put a few drops of CA, reach for a knife to grab the mix and fill...when fumes start to rise from the mix (like the ones coming out of a cigarette in the ashtray) and also toxic, while I was staring at it I felt one eye hurt. I took it out quickly and by then it ended. The pile was already rock solid and felt hot.

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Build log

Alex,

That's a neat trick being able to take an eye out and put it back again

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

ooops, 10$ for an EDIT button ?  

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Build log

I've seen that too. CA has a way of reacting with some stuff. The fumes are nasty without the EIRW, so keep your face and eye away from the stuff.
Um, that is, "eyes" if you got the other one back in ok.
(that must have really hurt!)

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I wonder if PVA works well for filling dust in the rosewood... 

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Build log

What you saw was the normal curing of CA in fast forward mode. It sets off by Ph, so the dust disperses it and the oil in the wood sets all of it off at once instead of from the outside in like with spray accelerant. The curing is a chemical reaction that creates heat, just like with Bond-O or fast epoxies.

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John Watkins
CNC Guitar Parts

thanks for the explanation !  

Perhaps I need to fill in the gap with dust first, then poor the CA over it ?

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Build log

Absolutely, I thought that's what you had done. The best results come when you a) spray the cavity with accelerant and let it dry, b) lightly introduce the filler material without packing it in, and c) drop thin CA in, letting each drop flash off completely before adding more.

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John Watkins
CNC Guitar Parts

If the gaps aren't huge .. on that combo I drop a very small spot of CA near the gap (not in the gap) and take a sanding block and sand the wet CA over the gap. Use a block and the dust it creates will mix with the glue and fill the gap.

But again, this only works if the gaps are small.

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

Thanks a lot for the hints ! Both methods make sense in their own context.

To put it nicely I have been silly, and expected the ca+dust mix will remain wet for a while and I could apply it as a putty. 

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Build log

One time, at band camp.....

no, really now...   I have seen this happen when accellerator and CA come in contact. Sometimes it will also bubble up and turn white.

 I had a similar surprise happen once with a tortise shell guitar pick. My wife had cleaned the house while I was gone and placed one of my tortise shell picks in a similar colored ash tray.  I came home, not noticing the pick in the ash tray and of course was smoking. Later that night I was snuffing out a cigarette in the ash tray when all of a sudden there was a LOUD explosion sending ashes and butts all over the place. Seems the pick had exploded under the heat and pressure of the cigarette.  I have tried to duplicate this several times, but havent been able to do it again.

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Reguards,

Ken H

Thats how I test if CA is fresh ... put a drop on some dust. If is smokes it is good. Why do you think it is call it "Hot Stuff." Be careful with soaking some up with a paper towel too, it will flash over quickly in that. I have had many burnt fingertips over the years, but with a little precaution I would rather use good fresh CA.

I worked in a shearing team years back. One of the older hands, a 55 year old shearer named Colie, had a glass eye. Once a week on town nights, we would leave the boredom of the latest shed behind and head into the nearest town to ride the glass canoe and wash away the dust and good health that comes from hard work.

Toward the end of these evenings, Colie, like clock work, would perform his standard party trick for any of those previously unexposed locals who may find themselves within ear shot. As he stood to head off to the mens room in order to make way for less of tomorrow, he would remove his one un-blood shot eye from it's socket and, upon dropping this expensive marble into his half full beer, would sing out in the most shakespearian of voices that a drunken shearer could muster, " Just keep'in an eye on me beer while I drain the dragon, don't let any B$#@%^d go skull'in the bugger will ya" or "I reckon I've just about had enough for one night, in fact...PLONK!...if I leave that bugger in there, it should see me through the rest of the week!"

CA glue was not in common use back then. If it had been more readily available, I reckon those of us in the team who had witnessed Colie in full flight enough times would have soon put an end to his antics for good.

Cheers

Kim

oztralians...I just love them....  I have a good friend in Ballarat, always having the funniest conversations with him.

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Build log

[QUOTE=Hesh1956] I have had good luck using Titebond and dust to fill gaps.

I just use my finger to pack the Titebond into the gap and then like Brock I use a block or tri-folded 120 sand paper and sand in the same direction as the gap. Sanding in the same direction as the gap helps the material, what ever it is, on both sides of the gap tend to not migrate to the other side of the gap.

Because Titebond remains wet for a while you can really pack the dust in it this way.[/QUOTE]

Do you get much in the way of shrink back using this method?

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

This run away reaction of CA is unpredictable and is the reason I'm very careful about how and when I'll use it. Once it turns white (often the over use of accelerator) in a joint the only way to get rid of it is to dig it out. The Titebond/sanding approach as described above is better for filling tiny voids and far safer. It also produces a result more like the surrounding wood.

Just as an aside, a long retired Martin employee once told me that they used a mixture of corn starch and linseed oil (boiled I assume) to fill small voids between the rosette rings and the spruce on guitar tops. I haven't tried this but would be interested in hearing results from those who like to experiment.

Best 

I noticed in one of the Robbie O'Brien clips that he uses sawdust to pore fill when French Polishing.  Could you use sawdust and Shellac to fill small gaps in rosettes and purfling next to spruce or WRC tops?  It would not create any adhesion issues, apparently.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Ken, that would have been a tortoise pattern celluloid pick. Genuine tortoise won't burn like that. Celluloid will practically explode.

[QUOTE=Dave White] Alex,

That's a neat trick being able to take an eye out and put it back again [/QUOTE]

TOO quick!!!!

Hesh, as I have not tried it yet, there is little more to tell, but I thought I would toss the nugget out there and see if anyone wanted to experiment. It is a legit tidbit from a Martin employee who started back in the 1960's. He said that is what they did to fill slight imperfections in the rosette ring fit.  

And the reason it happened?

 Sawdust. The loose dust has a LOT more surface area than a solid surface of RW, so the CA reacted violently.

1st semester chemistry....

the way you should have done it was to make your fine dust, pack it into the gap, then flood with the CA. There would be minimal surface area this way, and all would be fine.

CA is strange stuff. The curing reaction is very highly exothermic, and that's the situation where I see it turning white and voidy. It seems the heat from some of it kicking boils and burns the other stuff, rather than it curing properly. If I'm having problems getting it to kick, I spray the accelerator from about two feet away so it just lightly mists it, seems to work better.

As for the fumes...there are some things I do with CA that I'll only do outside. I've had that eye burn a few more times than I'd like. Whatever you do, don't heat the stuff up indoors...it's regular fumes times 100.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

I did this with CA and ebony dust...

Tried pre-mixing the ebony dust and CA to fill a small cosmetic gap on the side of my fretboard and voila nasty smoke!  I had my safety glasses on and the smoke irritated the heck out of my eye and kinda gave me a bit of a scare.

Moral of the story...Don't do that again