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I'm getting ready to glue up my next rosette. This one is going to include homemade tiles, as well as homemade rope and about 7-8 lines of purfling on the inside and outside of the tiles. My question is, what glue should I use? I've heard gorilla glue works well since it's not water-based and won't expand the purfling. Also, how do I glue the purfling in? If I only put glue in the bottom/sides of the channel, and then put in 7 strips of purfling, will the glue in the bottom hold the middle strips well enough? Any advice would be greatly appreciated.

Thanks!

John

Gorilla glue foams up and fills cracks like crazy. I would not use that anywhere on a guitar.

I build steel strings, but I have been using CA lately. As long as you seal the top well it works great.

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

I agree that gorilla glue is best for other purposes. Check this video out it shows how its done at the Taylor factory.

http://www.taylorguitars.com/video/factory-fridays/default.a spx?edition=6&title=6%3a+Rosettes

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Thank You and Best To All

John,
I've been quite happy with good old Elmer's white glue for this purpose. It is plenty strong enough for rosette work, and dries clear. Of course the Elmer's IS water based, but planning ahead for that, you can take advantage of this quality. If your trench has just a wee bit of slop (so that the rosette is not a "hammer fit" when dry) the tiles and lines will swell to fit in nicely.

The advantage to Brock's suggestion is that you can lay up the entire rosette dry. If it all fits nicely, then you can flood it with CA. But as he pointed out, you will want to have sealed the top first so glue doesn't wick into the spruce's end grain.

You could always practice on scrap if you are concerned....

Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

Steve hit it on the head. I seal the top with shellac and then assemble the rosette with white glue. I use white glue to build the rosette log layers as well because it dries clear. I build classicals and have not tried any other method.

CA seems like it would work as well if doing the dry fit method described but I just havent tried it.

Thanks fellows, it was very instructive for me as well!

SergeSerge Poirier38738.9666550926

Brock, I supoose you seal the top with shellac after the channels are cut so the sides of the channels can't soak up any glue. Is that right? Does the CA stick OK to the sealer than?

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

I like the CA idea. I might have to give that a try. It's always worked well on my bindings, I just wasn't sure it would be best for 7 layers of purfling.

Gorilla glue is the glue of choice for the rosette according to David Schramm (check out his online apprentice site). Gorilla glue is a polyurethane glue that will not expand the veneers. Waterbase glue can cause the veneers to expand as much as .010" which could really mess up the tile pattern which is done at .001". I'm just worried using only gorilla glue at the bottom might not be strong enough to hold 7 layers. However, it sounds like many here use waterbase glue and do the same so I guess there's no reason Gorilla shouldn't work as well. Actually, the foaming might force it into the purfling better.

I'll give an update after I try it.

John

John, there's no doubt in MY mind that if you get a good spread of gorilla glue on the channel bottom that it will hold everything. I've used a lot of that glue, but not on guitars and it sticks very well to anything I've ever put it on. But, it does foam like crazy. When it is about half hard it does clean up pretty easy.   I wouldn't have the nerve to try it a rosette personally, though. Not until I've seen the results from your build. Post pics when it's done, whether you use gorilla or not.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

[QUOTE=old man] Brock, I supoose you seal the top with shellac after the channels are cut so the sides of the channels can't soak up any glue. Is that right? Does the CA stick OK to the sealer than?

Ron[/QUOTE]

yes, exactly...

the CA sticks to the sealer just fine..   

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

Thanks Brock, i think i'm gonna be more comfortable with that method.

Serge

   WARNING WARNING WARNING! CA will turn some spruces yellow Often over time so what looks great today will be piss yellow in a year or 2.
     There are 2 glues that I use on rosettes. Sealing and glueing isn't a good idea as what is the glue sticking to? Glue either will weld or attach to. Sealing keeps that from happening.
    Duco cement for plastics and elmers for wood and pearl. works very well on rosettes. Gorilla glue is not a glue for any guitar. I used to use the CA on rosettes as you can keep going but after seeing a adirondack top turn yellow OUCH !!!!.
     Learn from my mistake. Duco has been used for many years at martin without any problems. It is good for wood plastic and celuloids.
    Good luck and have fun.
Learn from others mistake as you can't make them all yourself

Thanks John. I have used Duco on my bindings ever since Charlie Hoffman told me to and it has worked great. No yellowing.

I tried CA on bindings but for all the trouble I had getting the blasted binding tape off later, wow, it really wasn't worth it.

Everyone eventually tries everthing and settles on what works for them. I love CA for many things, it's really good stuff if you can handle the fumes.

Thanks for your expert advice. It means a lot to have insider info on what factories do that works.

CA works fine with spruce, but you really have to seal whatever you're gluing in with shellac first. This goes for rosettes, binding channels, everything.

I hear you John. You are right about it yellowing. You definitely need to do a good job sealing.

However....

If you are doing complex glue ups I find that nothing beats this method. Scotch makes a brand of clear packing tape that CA won't stick to and it doesn't loosen the bond. (I am hunting for the supplier and product number now).

Certainly this isn't the only way to get the job done, but I have had pretty reliable results.

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

I can't find the product number on the scotch tape that works, but here is one that works as well for the CA method. Clean up is much easier.

3M 622 tape

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

Hi John,

Good idea on the Duco cement, I never thought of that. I'm curious though why folks here are so against using Gorilla glue on a guitar rosette? It's being used on some of the best made classical guitars in the U.S. (John Gilbert [his son], Schramm, etc...) Is there some property about it that you think makes it inappropriate for guitars? My main drawback from using it is the longer dry time. I don't mind the foaming because it cleans up perfectly fine. As a matter of fact, I used Gorilla glue on the solid maple rosette I posted in the other thread.

Cheers!

John

I personally hate the stuff.Maybe on rosettes okay but nowhere anywhere on the guitar.
john hall

John, never used the go-rilla, but seems like it passed everyone's muster the other day when you posted that beautiful rosette. Every time I hear of the foaming thing it takes me back to when I was a lad of eight years old.

In my neighborhood was a big dog, like a boxer. It ran and ran all over, slobbering and foaming at the mouth. Finally, it died. We all gathered 'round to see that poor animal, foam and all. Quite heart-wrenching. Rabies!

I don't find it at all surprising that I am with Steve Kinnaird on this. I always make my channels for the rosette slightly oversized, and take advantage of the fact that the glue expands the purflings, etc. I use titebond for this, and I use a bit of water in the channel ahead of the purflings to effectively thin the glue that is added thereafter. The glue wicks up between the purfling just fine and everything goes smoothly.

Later I "top glue" the entire rosette with watered down titebond.

In general I inlay the middle tiles first, then route for the borders and inlay them seperately, afterwards.

According the Eugene Clark this is the old Spanish method.

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Instagram: @jfrenchluthier
Web: https://www.jfrenchguitars.com/

I've used polyurethane on lots of rosettes, and never had any problem. I usually use abalone with two or three purfling lines on each side of the shell. I get a nice press fit, then put glue in the channel and on the purfling strips. Then I put the purfling strips in and press the abalone between them. The only time foaming is a problem if if there are gaps that the foam fills.
I also use it for my soundhole binding because from tests I have done polyurethane works best on end grain joints, and a lot of the soundhole is endgrain.

                   Paul Harrell

Joshua--good idea on thinning the Titebond. Many thanks.

Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

Whenever I read of people "flooding areas" with CA glue I have a small heart attack. I don't have any superglue around the place at all. After one exposure to it and the sore eyes and chest tightness I checked on the safety sheets at the lab. If we used it in the laboratory, safety rules would mean using it in a full air flow fume cabinet. It can be nasty stuff in quantity.

like others here I use titebond and like the way it slightly swells the purfling and rosette for a nice tight finish. I like the water trick too Joshua, always learning.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I saw a lecture by Kevin Ryan at the 2000 ASIA show in Nashville, and he favored using super glue after putting the rosette and bindings in "dry". Sealing the end grain first is a must. I used shellac to seal a cedar top, and found the alcohol in the shellac dissolved pigments and brought them to the surface. Then sanded flat, the sealed areas were lighter in color than the rest of the top. Not enough pigment left to re color the areas.

I later bought some water based shellac from Target Coatings, which seemed like a good idea, but it didn't soak into the wood enough to give it good adhesiveness for a sealer. However, I have enough for many guitars to use as a sealer for the end grain and on the adjacent top to keep thin CA from soaking into the top or the end grain. It later sanded off completely without any color change, since the pigments are not water soluable. It does swell the end grain some, requiring a looser, original groove or channel, but does keep the CA where you want it.

As far as gluing bindings, I agree that getting the brown tape off later is a real chore. However, I've found that using a small amount of CA inbetween the tape placements of about an inch apart, spot welds the binding in place. I then remove the tape, and flood the bindings with CA. I tape both thumbs with clear packing tape to hang on to most of my DNA, so that I can just hold the bindings in place around tight curves of the cutaway and waist as I spot weld them in place. I have found that CA Gold seems to set up more quickly than others I've tried. Less holding time.

I then use regular shellac as a sealer. After going through beginner's hell, I now use Target Ultima water base lacquer over the shellac. (800-752-9922, 201-804-0993). It is more forgiving than other water based products I've tried in terms of blushing white with too much (although it can give a translucent purple cast with too much--which very slowly clears) and has excellent burn in. They claim it's harder than nitro. At the Healdsburg fest, Charles Fox said he now uses Target Ultima. Also, it doesn't get as hot during buffing as nitro, and I was able to speed up the wheel without melting the finish.

Scott

Don't the instructions for Gorilla glue tell you to spritz the surface with water and then apply the glue? I remember after reading that on the bottle just putting the stuff down and deciding it wasn't for building guitars.

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Joe Breault
Merrimack, NH
Perpetual novice