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Hi all.

A customer is interested in having a brass rosette. He has a friend who would make the rosette for him so I don't have to worry about that. What makes me not confortable is how I will inlay this!

Here are a few questions:
- Will CA glue hold on well to brass? (Or should I use epoxy?)
- When sanding level the rosette after inlaying it, will the sanding dust pollute the crap out of the soundboard? Will it start to rust/oxydise after a few years and start showing small green dots all over the place?
- Will my finish stick on this thing? (I use polyurethane)

I can and might test most of those, only the oxydiation thing I can't test. But If I can get some answers from experienced people, I'm all ears to who ever tried inlaying brass!

Thanks!

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Alain,

Use epoxy. Make the rosette thin enough that it can be covered with epoxy also. That way you won't have to worry about the brass contaminating the top when sanding.

Steve

Hmm, not a bad idea!

But then wouldn't I have to worry about bubbles in my epoxy? (I never managed to make bubble free epoxy...)

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I was talking about the idea of using brass in inlays and such with a few folks at the ASIA Symposium. The consensus seemed to be that there would likely be problems with oxidation/tarnishing over time, and that even if there were no finish adhesion problems at first, there very well may be later. I don't have the experience to back this up, I'm only relating what others were saying, and some of them seemed to have the experience on which to base their statements. The advice I got was to use gold.

I wonder if some of the people here who do a lot of inlay with a variety of materials would have some helpful comments on this question.

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Todd Rose
Ithaca, NY

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

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

Try this, it worked for me when I used tinted epoxy to fill a circular cavity around my logo. Mix and pour your epoxy then take a dremel or other "noisy" tool and turn it on high and rest the body on your top near the rosette. The vibrations force the bubbles to the surface. I think I saw that trick used during a documentary about the construction of the Hoover Dam.

Good luck,

Bob

Brass tends to turn green under finish after a while. Doesn't look nearly so good then.

_________________
Jim Womack

"Be thankful we're not getting all the government we're paying for. "
Will Rogers

Thank you very much for all your inputs guys!

I guess I'm going to follow my instinct and suggest to my customer he sticks to standard material!

Thanks again!

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

FWIW
I used brass brads for fret dot markers and they still look gold coloured and fine

I would think that with the proper finish (but I don't know what a proper finish is for brass) that it would remain.....brassy looking. My concern, on something as big as a rosette, would be the different expansion rates of brass and wood. Next question, are the expansion rates of brass and wood different? I would guess so but I'm only guessing.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I am pretty sure most brass beds are lacquered ... they dont turn green all that much now do they ???

I used brass for a FB inlay years ago .. it tarnished, but didnt turn green.

I am pretty sure Grit Laskin uses brass at times as well .... Michael Greenfield uses brass tubing as side markers sometimes.

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

If it's covered with finish, it'll be pretty hard for it to oxidize. There's not a massive amount of strength needed to hold it in, the joint's never going to be stressed. You can hold brass to shell well enough with CA, so it'll hold to wood even better. I did a bunch of little logos for Peter Marreiros with brass borders, and he's never had any problems. Here's one rough (pre-polish and level) and one of 'em in a headstock on his site:

http://www.cornerstoneguitar.com/The_Gallery.html#41

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Sorry, brain fart. Was thinking "copper".

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Jim Womack

"Be thankful we're not getting all the government we're paying for. "
Will Rogers

Well there is copper in brass so not that bad of an assumtion. But I just remembered that I had a brass penny whistle in my glove box that's been there for about 8 years that was coated with lacquer. It hasn't been touched for about that long either. Now it wasn't covered with CA but here you go. I have gold side purfling on the wood reso in my avatar and it was just glued in with CA. You would have to polish the brass if you scratch it when installing it which could be a bit tricky also. But under poly who knows? I wouldn't worry about it coming out if it's CA glued and under poly either. You might also want to consider if it's in contact with any woods with acid or tannin content that could tarnish it too. Some people will touch brass and leave a tarnish finger print on it. A lot of ifs. Might be worth it to make a test block for the future use of it.

Inlay and cover with epoxy as suggested and then use a hair dryer (not a heat gun because epoxy has a very low boiling point and you DON'T want to be doing that) to gentle warm the epoxy. This will thin the epoxy considerably and also expand the air in the bubbles making them larger and forcing them to rise quickly through the mix and out the surface.

It is a technique used to expel air trapped between the cotton bindings which hold on fishing rods runners and decorate the butt of the rod after these have been given a protective coat of epoxy to lock the bind. I can tell you with some qualification that this method works very well as I have done this many times in the past with good success.

It is worth remembering that epoxy generates it's own heat through chemical exchange so when you think your nearly done with the hair dryer, it is time to stop. Don't keep heating until it's all crystal clear as the mix will keep building heat for a little bit before it begins to cool again and this should clear it of air just nicely. If you take things too far you will actually create bubbles in the mix when it boils and ruin the curing process. Do it right and the mix will be clear and the heat will assist the curing process.

Cheers

Kim

Here is a link to some good 'embedding' material from TAP plastics. They also have great videos and docs on working with epoxies and plastics, including avoiding bubbles. http://www.tapplastics.com/shop/product.php?pid=75&

-Matt