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I think this is a pretty basic question but I've always done plastic rosettes.

I'm doing a simple wood ring with plastic.

The wood is Cocobolo.

My question is what strategy to you use to seal & pore fill the rosette without discoloring the top wood?

I'm worried about the cocobolo bleeding onto the spruce if I try to use CA or the CA itself discoloring the spruce.

Maybe a coat of shellac to seal the spruce first?

Thanks.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

shellac blonde dewaxed . 2 thin coats

You spray?

I guess I could experiment but I assume brushing it could cause the Cocobolo to bleed also?

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I can , but use a FP rag or a good artist brush , spraying a one off job on a top requires gun cleaning

I'm not sure if this answers your question exactly, but what I have done is:

1) Spray the top / rosette area with rattle can shellac.

2) Using a gloved finger spread z-poxy as a pore filler following Todd Stocks videos on YouTube.

3) Sand back down to the spruce / filled rosette.

For the B&S I have been leaving a thin coat of z-poxy on before finishing, but for the top I was worried about having just the spruce around the rosette discolored so I take it all the way back to wood leaving just the rosette pores with epoxy in them. Hopefully that makes sense and is at all helpful.

Brad


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I would typically seal the area with shellac or whatever sealer you use and the fill with thin ca. Once it cures gently scrape back and sand level. Same could work with epoxy, but with such a small ring I would stick with ca.

Thanks for the replies.

That got me thinking. I have an aerosol can of Behlen's/Mohawk vinyl sealer which is what I seal the whole thing with anyhow.

I'll test some on a Coco scrap & follow with CA.

Thanks again.

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Having installed a few of these before I ran across the same issue. I tried to mask off the ring and do a coat or two of z-poxy. Worked well on all but one top and what a mess to deal with color-wise. I plan to do as those recommend and get a coat or two of shellac before installing. I may try to z-poxy the ring top before installing if it is close to top thickness at installation (or even flood it prior if it needs thickness sanding). Anyone tried that technique before?

all i do is add some egg whites, let it sink, dry and sand. as to pore fill the wood rings, i like to do the bulk of it with CA before i rout them out of the blank (so, before inlaying). but that´s mainly because i don´t have easy access to epoxy here, and being a small area CA isn´t that hard to use.
after the ring has been inlayed, egg-whited and sanded i brush a little shellac with a small artists brush. A little CA here and there can eliminate any problem areas that might have escaped. never tried this with coco, though.

do you think epoxy would save me time/produce best results?

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My last guitar has a cocobolo rosette ring. I sealed and filled it with z-poxy applied with a latex-gloved index finger tip. Your ring looks like it might be a bit narrower so a different applicator might be needed. It worked fine with no bleeding

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I wouldn't worry about CA staining the top if you scrape it off completely. It's having it wick into the end grain that can cause trouble.

Is there any reason you can't carefully paint a layer of med CA let it dry, then scrape back to wood?

Am I missing something?

CA can wick into end fibers, always a risk at certain points on any circle. It's not predictable. But if it reacts poorly, you will get yellow steaks that you cannot get rid of.

I guess it depends on how it was put in, or with what glue.

I use CA to put the rosette in so my channels are already always sealed with shellac anyway.

It's not Coco. but I've successfully sealed IR bindings by wiping them with 1lb shellac on a paper towel, 1 swipe per towel then ditch it.
Let it dry, apply second coat, then pore filled them with CA (rest of the guitar didn't need any)
No bleed.
Read about it in an article about an old-time luthier doing varnish finishes as a way to prevent bleed.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Just to follow up.

I sprayed the area with vinyl sealer, pore filled the wood ring as carefully as I could with CA - it seems like it's either too watery & runs everywhere or the medium stuff has too much surface tension, beads up, doesn't flow, and I have to push it around.

I then scraped off the excess. My concern was that the CA would soak too deeply into raw spruce and I'd have to scrape away too much material to get rid of the dark shadow. Sealing with vinyl dealer prevented this.

In the future, I need to seal the rosette channels and the surrounding area with shellac before installing the rosette. I've always used binding cement which doesn't soak took deeply into spruce & discolor it.

Thanks again for all the help.

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Fwiw, here's how I do...

Cut the rosette channel and then install all rosette pieces to test fit, uninstall, seal with 2 coats shellac, reinstall, flood with ultra thin ca...