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View Full Version : What do you put under your CA finish?



Eric Schatz
12-05-2017, 10:50 AM
I've been puting OB Shine under my CA with mixed results. Wondering if the oil is messing with my finish. What do you all use? I'm trying to put finishes on pieces really quickly. Making money this season and hustling.

Thanks

Bob Bouis
12-05-2017, 11:19 AM
On pens I've put straight boiled linseed oil under CA in almost every pen. Don't really wait for it to dry, either, and never had any issues with finish sticking.

I've also used friction polishes and straight shellac. Never any issues with those either.

Maybe your shellac is old?

Kyle Iwamoto
12-05-2017, 11:38 AM
For pens I don't use anything under the CA. Have not tried to use BLO or anything. I'm happy with the look of CA alone. Maybe I should try?

Bob Bouis
12-05-2017, 11:45 AM
BLO darkens the wood a bit and gives it a bit of an amber hue (CA doesn't) and enhances the depth of the grain on chatoyant or figured woods (more than CA). Most of the time I consider both of those effects to be desirable.

Marvin Hasenak
12-05-2017, 11:52 AM
I use BLO under CA. But I rarely use CA, most of my customers won't buy the plastic look. More work, but I use several coats of oil finish.

Alan Trout
12-06-2017, 1:28 AM
Never ever put anything under CA unless it is fully cured. Linseed oil take about 6 months or so to cure fully. If you put CA over uncured linseed oil it will shrink and cause the CA to do some pretty goofy stuff as the Linseed oil cures.

Good Luck

Alan

Bill Blasic
12-06-2017, 6:10 AM
I know of no one that finishes with CA that is better at it than Alan Trout. For me he is the master of the process. I have learned most of what I know about CA finishing from Alan. I wrote an article on CA glue for the American Woodturner and mentioned the process that I used which used BLO in conjunction with CA. Alan contacted me and through the process of emails and calls showed me a better way to use CA. I subscribe to that process as it is so much better than what I was doing.

Prashun Patel
12-06-2017, 8:14 AM
I would also vote for CA over raw wood.

If you have to put something underneath, I would use Zinsser Sealcoat - or some other dewaxed shellac. It'll dry in seconds.

Also, FWIW, when I get into Holiday Season, and need to finish @ production level, I spray. If you don't have HVLP, then good options for me have been spray cans of Behlen's Stringed Instrument Lacquer, Zinsser Shellac, or Deft Spray Lacquer.

John K Jordan
12-06-2017, 8:28 AM
Oil itself shouldn't interfere with the CA. Some of the instructions for a CA finish include a bit of oil applied at the same time.

But after reading stories elsewhere about CA finishes not holding up in the long run I'd worry about that. I quit using them. I prefer multiple coats of oil for things that get handled (made of some woods) since the oil penetrates the wood and hardens - further coats build on the surface. But this is definitely not a get-it-out-the-door finish!! I usually take 4-6 weeks to apply 6-10 coats, letting each cure before applying the next. I have no idea about what to use that is quick to apply and durable for the long haul. Lacquer? Poly?

JKJ

William C Rogers
12-06-2017, 8:57 AM
I don't put anything under the CA. Now I only use thin ca about 15 coats for pens. A long time ago when I was using medium I may have used blo.

Marvin Hasenak
12-06-2017, 2:39 PM
On larger items the BLO may have some effect on the CA, but on small items like pens and bottle stoppers, that method has been used for a long time without problems. For me, the larger items will always have the handrubbed oil finishes.

Alan Trout
12-06-2017, 10:14 PM
Mark, It does cause problems. I discovered that the hard way many years ago. What happens is that all finishes shrink as they cure, even CA. BLO and all other non catalyzed drying oils are extremely slow cure. Many times it takes 6 months plus for all of the solvent in the BLO to evaporate. As it evaporates it shrinks. If CA is over uncured BLO or mixed with the CA which cures much faster than the BLO it will shrink and the cured CA will distort. After many months it will develop texture or just outright fail. I have seen both happen many times. Another issue is why would there be any need to add an extra step or chemical into the process? There is a lot to be said for the "KISS" principle. I do small items and I have done pieces over 16"x9". It is my standard finish on my large gallery and collector pieces. There are two things to make sure of the archival quality and durability of a CA finish. Number one is to use only CA, number 2 is to make sure the piece is fully sealed inside, outside and all edges. Expansion and contraction is the enemy of a CA finish I now have large pieces over 10 years of age that look as good as the day the finish was applied. When properly applied a CA finish is as durable if not more so than any clear gloss finish. I am just trying to save people from the heartache that I learned over the many years. I don't post much and generally I will only post when I have a lot of experience and can add valuable Commentary. If anyone sends me a PM with their email I will gladly send the handout that I give when I do my CA finishing demo and answer any questions. Sometimes I am a little slow on my emails and I do not check the Sawmill creek everyday just because how busy I am but I will get back to anyone. This piece was right at 15" tall. Currently it resides with a collector.

Good Luck,

Alan