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Quick question: Has anyone used ethyl cyanoacrylate for flooding a shell and purfling rosette? The product I have is a brush-on "krazy glue." My concern is that it could be different than the formulas you all have had success with (potentially leading to yellowing or opacity or something). If you have not used that type, what brand/formula of CA do you use with success for flooding rosettes?

Thanks,
Peter

Peter, I haven't tried it, but I would recommend you try it on some scrap first. Seal the end grain with some shellac and give it a go there, simulating a rosette channel.
Some of superglues can turn spruce sort of a greenish/yellow color. Not good

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Jim Watts
http://jameswattsguitars.com

Peter, "krazy Glue" is a very thick CA glue (thus the brush) and probably would not flood much. Go to Stew-Mac, LMI, Woodcraft, etc. and get some medium and thin CA glue - test those to see which one works best. I use both thin and medium.

Thx, Tony

Example of different CA viscosity:

http://www.stewmac.com/shop/Glues,_adhe ... _Glue.html

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Tony Flippo

Thanks, Jim and Tony for your reply.

Tony, do you use both viscosities for the purpose of flooding the rosette?

Thanks,
Peter

I just use thin for rosettes and bindings. Med will not "wick" in enough.

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Thin CA from LMI (for example) works great.

Just be sure to seal the channel with shellac, prior to flooding with CA. Otherwise it will wick into the grain of the spruce (or other) top and stain it a darker color.

CA can cause spruce to turn yellow . I havn't used it since that happened to me and I don't really see an advantage of CA. using duco and tite bond I can still have a top rosetted within an hour and thicknessed. Sealing with shellac may stop yellowing but takes longer than duco and tite bond.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Sealing with Shellac takes longer then letting titebond dry???? Not in my shop it doesn't???? All you need is 10 mins and the alcohol has flashed off a seal coat of shellac, then one can install the rosette etc... It doesn't need to be rock hard or anything.

I've used AR glues for rosettes, and it works just fine, but I find I can't control the amount of swelling that the channel or purfling lines will do when using AR glues and I just get frustrated. With a nice tight dry fit with the purflings and rosette you will get swelling to the point where they will not fit. If you open the channel up a bit more, once everything is cured the swelling goes away and can leave gaps. This is my experience anyway. I know it works fine for others though....

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Butyl based CA is supposed to be better for wood. According to an on going art conservation research lab in Canada. I wrote them a few years ago about CA conservation issues. The findings were that butyl was more durable if there is any chance of the wood wicking moisture to the CA.

I can't remember the name of the lab off the top of my head, but it's in my papers.

Personally I don't like using CA to fix or fill rosettes because it makes the color change in a way I don't l care for. I use hide glue if I can and CA to fill any tiny pinholes after a few coats of shellac are on the top.

I also begin brushing shellac on the rosette while I'm assembling the body. By the time I get to finish work I've already built a good body of shellac on the rose. For whatever that's worth.

If you have a local 'hobby shop' that caters to aircraft modelers, it will have a good selection of (fresh) CA adhesives as well as pipette tips, debonder and accelerant.
I find that the small aerosol cans of accelerant are more effective (and thrifty) than the pump-style.
One 'trick is to spray the rosette recess with accelerant before you put in the rosette- the theory is that it will help to prevent the CA from wicking into the top wood. (I pre-coat with shellac first anyway- the old 'belt and suspenders' idea )

Cheers
John

I seal with shellac first also. I get the little tubes of CA from Harborfreight when on sale. Use a tube throw it away and get another tube. I use those capulary tips when it's called for. But for rosettes just the tubes. Not all CA will yellow the spruce. I have a large bottle of med. for certain jobs too. I like CA for rosettes and inlay. But each to his own.

Thanks so much for the help, everyone. I got the rosette in, no problem!

Small gaps from somehow budging my laminate trimmer a bit during one part of the circle. Not really noticeable except when looking for them.

Flooded with CA, but somehow (maybe because I did not use accelerant) it did not harden very glossy or even consistently. In a few places, the CA migrated away from the center of the shell inlay, causing me to have to sand back to the abalam.

Has anyone else had to sand back to the abalam? If so, do you sort of "polish" the shell back up before finishing?

Thank you all for your help!
Peter

The CA won't alway dry to what looks like clear, surface not level or some air bubbles and it will need to be polished just like any clear finish. The Abalam will also need polished as it's mostly always sanded especially in a fretboard unless you happen to set it deep enough. I try and set my rosettes and purf about .005" deep and cover with CA. I don't like to use accelerator a lot unless it's needed as I find it seems to cloud up the CA sometimes and even make it white. Plus it's one more chemical to buy and smell. But each to his own. I will also glue the rosette in and at the end go over it and flood it so that there's a fine film of CA covering it, thus the term flood as opposed to glue. Especially if there is wood in the rosette or inlay. It will seal the pores and keep dirt and oils out of the pores, especially in a fret board. It's also not a bad idea to put wax paper under the top when gluing with CA especially if you have placed pieces using pins and incase there is any kind of a gap in the centerline glue joint. The CA can weep through the small pin holes or any cracks or gaps and the top can get glued to the bench top. Better safe then sorry and use the wax paper backing.