Ca blistering

[yorkie]

This is driving me nuts!

I find that sometimes when I use CA, I get blisters around the tip of the blank and sometimes under the CA itself. It causes me to have to sand back to wood and start again.

When I'm done finishing, I finish between centers but without the bushings, I will use the sanding share to shave them flat or use a pen mill slowly to spin off any excess ca. It's hit and miss whether or not this causes the issue. If I get it on the tips, I dip in thin ca to wick up into the blister and that works fine. However, the blistering under the ca or sometimes I get a shiny shimmer under the CA which almost looks like air in clear acrylic blanks.

I use the thin to seal the blank and medium to build up 7-10 layers. I find it gets worse, the more layers I build up.

Maybe it's time for an alternative to CA that's just as shiny and durable.

 

[longbeard]

Do you have pics? that might help someone to help you.

 

[Wildman]

Have you tried wiping down pen blank with alcohol or acetone before applying CA?

Doesn't take much alcohol or acetone or time to dry.

 

[yorkie]

I always do two things before i apply the ca. I wipe down the blank with denatured alcohol and then i rub BLO into the blank, both while it is turning on the lathe. When I do the BLO, i hold the towel against the blank to build up heat. I also build up heat on the ca as i do the final polish.

 

[yorkie]

What do y'all sand to before you CA? I've been sanding to 2,000 and sometimes to 12,000 before I BLO and then CA.

 

[KenV]

I suspect Heat is likely the key culpert.

CA softens at about 140° F. It goes downhill fast as the temperature rises.

 

[yorkie]

i wondered if heat build up was part of the problem.

I suspect Heat is likely the key culpert.

CA softens at about 140° F. It goes downhill fast as the temperature rises.

 

[Wildman]

Sanding depends upon the wood, not sure need to go past 600 grit for a CA finish. I did wet sand/polish once applied CA with micromesh. Some folks sand more and use micromesh dry after final coat.

BLO mostly mineral spirits or naphtha depending on brand, so putting that on after NDA, might be messing with CA finish not sure. I stopped using any oil with CA finish just felt an unnecessary step.

Reading your post, you are using friction finishing technique. Applying CA to a pen barrel all about building a film finish, each coat adds another layer of film.

I have applied CA with lathe on 500 RPMs and lathe off, waiting few seconds or minutes between coats. Some folks sand between coats, I never have unless saw a problem with previous coat.

Think if omit BLO, just wipe on CA, wait to dry, recoat, whether lathe on or off life will get whole lot easier. Not sure ever took 10 minutes to complete a CA finish.