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Was wondering if anyone has had any problems with staining from CA glue? I started using Hot Stuff thin ca to install bindings/purflings and rossettes. I would get a nasty yellow stain where the glue was applied. The stain would not appear right away but weeks later sometimes after the finish was applied. I put on a barrier coat of shellac before the channels were cut which did not help. Also I did not seem to have the problems with sitka or cedar but did with red and carpathian spruce. Any advice?

Thanks Brent

All channels should be sealed with shellac when using CA for bindings or rosettes. It will usually stain spruce if left unsealed.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

yep .. seal it - I use the bottled french polish (padding lacquer) from Lee Valley.. I found the same years ago .. sitka/cedar/redwood seem to not care, but engleman and red are terrible . they turn yellowy/green ....

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

Yes, seal the channels "after" cutting the channels or cavities. There are some CA's that won't discolor depending on the chemical make up. But you would have to do a test to be sure which ones they are. Better to still seal as the CA company may change their formula. I'm pretty sure that happened to Mario awhile back. Be sure to seal the end grain of the channel as that's where it will suck up the CA the most.

Thanks for the help. I'll try sealing "after". I did'nt because I thought there might be an adhesion problem.

You don't have to worry about the floor just the sides and top. And not real thick. A 2# cut should be fine.

In Sergei deJonge's building course, I was taught to pre-apply 'accelerator' to the rosette channel edges. That 'sets up' the CA before it can wick into the wood.
It seems to work.
Since we were using 'doublers' under the rosette areas, everybody in the course added CA 'from underneath' (later) to make sure the back of the solid rosette inlays were well adhered. The doubler hid the holes.
It pays to do some testing on this stuff- some CA glues I've used seem 'hot' enough to burn through a thin shellac layer.

Cheers
John

I have also had CA stain Sitka.

I found CA stain even with pre accelerator. I use Duco for the rosette. I can install a rosette by the time you seal with shellac. I see no advantage with CA on rosettes or binding.

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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

I like hide glue for soundhole rings.

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

I used duco on my first attempt at binding and it was a big mess and didn't hold. I was turned on to Mario's technic of using CA and threw that model glue away in the box and use it to temperary set inlay pieces to scribe around. But then again I couldn't get it work on models when I was young either, just got a head ache. Each to his own.

Your experience was much like mine Chris. Using Duco definitely takes a touch, at least in my mind.

I've had CA ruin tops because of the staining issue, even on sealed tops. Maybe I missed a spot I don't know, but I don't think so.

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Jim Watts
http://jameswattsguitars.com

I have used the Smith brand thin CA both in building Model airplanes and Guitars and have not had any issues with staining but on guitars I shellac my tops just in case. On balsa wood it always cures clear but I have not taken a chance with this on spruce. Most hobby shops carry this glue often with their name on the bottle.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Fred,
Do you have a cut off from a spruce top that you could do a test on?

If you use CA anywhere end grain is exposed or anywhere for that matter on soft woods, seal with shellac prior to applying the CA. it will penitrate deeply. sealing with shellac will prevent this. After is too late

Duco works so well but the techniques is 1st , don't read the instructions. Have plenty of tape available the when you put on the Duco or weldwood , lay in a nice bead , wipe the binding into the glue and tape. Work about 8 inches at a time . Allow to set overnight and that is all. The key is the wiping step. I leaned that trick at CF Martin. I like old tee shirts but paper towels will work. Then when taping you think down then in and that is all.
Rosettes are so easy with duco that you just put duco into the channel rub the material into the channel and that is all. If I am using wood I use tite bond.

_________________
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

Funny you should ask Chris I was thinking of doing that today as I am finally done spraying lacquer. I will try a test on some real white Engleman. Us wire pullers must be on the same wave length though I try to stay away from wires since retiring, my table saw is still waiting for a power drop.

Fred

_________________
Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Just to make sure I understand this (since I will be doing it soon):
-I route the binding channel
-I brush on shellac into the channel (and some onto the top ?)
-then I glue the binding with CA

I have no experience with this but I wonder if the shellac on the top will sand off, or if will show thru the final finish (which in my case will likely be polyurethane). Or maybe I should seal the channel with poly ? Would the CA adhere to it ?

It never hurts to check the tutorial section of the forum.
viewtopic.php?f=10117&t=20493
It's getting pretty lengthy these days. Glad to see it.

Shellac will sand off without any problem As far as the poly, Polyurathane polyester, poly has a cracker. Sorry I could not help my self. The CA is going to stick to darn near anything but shellac is better choice IMO

Thanks for making those videos, they are great.

I still am curious about my questions though.

Like Fred mentioned it's not a bad idea to shellac the whole top sometimes at the start as it helps to keep the top clean while working on the rosette and just handling it. A slight coat will easily sand off. And as mentioned in my tut it also helps to keep the tape from pulling up the soft fibers of the top when removing the tape. Shellac is used for a sealer because it pretty much sticks to everything pretty well and seals the wood from any contaminates that might leach into the finish and most finishes stick well to it and it is a finish too. It doesn't hold up against Alcohol which will disolve it.

I think I've mentioned this before somewhere, but I once bound a cedar top uke with plastic using CA, taking the precaution to seal with shellac both before and after routing. Well the binding lifted in the waist while I was scraping or sanding, so I gave it a squirt of CA to stick it back on again, and got a stain that wouldn't sand out.

Then I did the whole top with CA, and when I sanded it off the stain disappeared.

Now I wouldn't rely on it working again, but if you've still got the stain, I think it's worth a try.

Good luck
Hip.