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View Full Version : Trying CA glue as a pore filler for the first time



Vespa Bob
03-14-2015, 03:41 PM
After reading about using CA glue as a pore filler, I'm about to give it a try. A couple of questions: Can I use CA over water and oil based stains, or, to put it another way, are there any types of stains I should avoid? Approx how many oz will I need for a concert sized Ukulele? I realize that I will need a "sticker coat" of shellac before applying the lacquer finish. The instructional videos so kindly posted will be a great help. Thanks.

Bob

Michael Smith
03-14-2015, 08:44 PM
I think you will be able to do it easily with less than 1oz. Folks on this forum have demonstrated using rubber gloves and a small pice of cloth and applying with circular motion. That method doesn't work well for me. I have found it easier to squige it on with a credit card on every area other than the neck. I use less and it seems to go into the pores better. Wipe credit card when you are done and run it back and forth on some fine sandpaper to make a clean edge. On the neck I use my glove as I would epoxy. I have never used CA over oil based stain so no help there. Certainly over a dried water base stain you won't have any problems.

Vespa Bob
03-15-2015, 09:32 AM
Thanks for your reply, Michael, it's good to know that it doesn't take much CA to do the job. I like your squeegee method too. I'll try your method on the back and the other on the front!
Bob

Chris_H
03-15-2015, 12:14 PM
The Bounty paper towels, as suggested by Chuck, work great. At first the CA glue wets and flows well, and then it hits a stage right before it starts 'going off' where he paper towel fold starts heating up, and the filling actually happens. CA for grain fill works great.. Kinda like wiping a stain though, some technique is beneficial to minimize the amount of sanding necessary to bring it all flat again.

Pete Howlett
03-15-2015, 12:46 PM
I do it for my headstock veneers but can't seem to get it right for the body... still usding Smiths Industries finish epoxy to good effect.

Beau Hannam Ukuleles
03-15-2015, 01:19 PM
I found with Bounty paper towels the CA goes off way quicker then with some other cheap brand of towel I get. I prefer the "open time" of the other brand (brand unknown)-
That bounty towel (for me) sets the ca off quicker might have something to do with that Bounty in much thicker paper which, therefore, absorbs more moisture in the air as CA is set off by water content. (see below). Old T shirt sets ca off very quick.

The following is from - http://www.ipmsstockholm.org/magazine/2004/10/stuff_eng_tech_ca_glue.htm
"How it Works
The cyanoacrylate glue hardens very quickly when trapped between two surfaces. The reaction is caused by the condensed water vapour on the surfaces (namely the hydroxyl ions in water). The water comes from the surrounding air, so obviously the air humidity is a factor that may affect bonding capabilities, or cause them to differ from application to application."

Chris_H
03-15-2015, 03:55 PM
I have not done many instruments, nor used this method a lot. However, I do remember that the period of time when it is just starting to kick, as being the most productive time for the actual filling. Not when it is wet and flowing. When the towel folds kick to beyond usable, they are replaced by another one waiting close by, in a pile of them, actually..

RPA_Ukuleles
03-15-2015, 05:03 PM
I feel like paper towel and cloths accelerate the CA cure, but I have found that applying CA with small wedges of foam rubber, (like seat cushion foam) don't accelerate the cure and give a bit more "open" time. I pour the CA into a tiny dish, then dab the foam in to pick up material. If you dab back in at the right interval, the next dip will keep the previous from curing in the foam. However if your technique is to rub firmly to force the CA into the pores, the foam is a bit soft. With some trial and error, you can fold the foam into a firm pad of sorts. I may try making a foam "muneca" applicator - similar to french polishing. Otherwise, simply wiping it diagonal to the grain with the foam pad works pretty well. Could always wipe on a stroke with the foam and then a pass right over it with a credit card.

Doug
03-16-2015, 06:33 AM
I use paper coffee filters. Cheap and no lint.