Tiny bubbles

[RVG8tor]

I am using the inside of the skirt to learn how to do the final finish, I really don't care how the inside turns out so it has been great for learning to use these materials

I put on a second coat of straight epoxy (West Systems) after sanding off a primer layer. I used a 3" foam roller from the home store used for smooth walls. It rolled on real nice but as it dried there are tiny bubble areas, they don't look like pin holes from voids in the glass. So I am guessing that a sanded layer of primer will cover them over but thought there might be a better way to prevent them. I am not working in ideal conditions, it is winter and I can only keep my basement garage at 62, so cure time is really long, it takes the full day.

I thinned the first layer but it was too much like water, but it did make a nice smooth finish. Thank you for any pointers, I have read DanH tips and those have been a big help.

Cheers

 

[Allan Stern]

Inside canopy skirts

I took a can of trunk paint and painted the inside surface of my 8A skirts. Saw this on an 8 at Oshkosh and it looked nice and my result turned out very well. Otherwise, you could cover it in cloth like some people do or paint over it.




8A "My Little Kitty"
Lycoming 180, C/S 57 hours

 

[Flyguytki]

Hey mike, it sounds like you are getting similar results as you would when you paint a wall with a roller, you usually get a lot of bubbles that pop and just leave holes.

What if you tried using some of those cheap foam brushes? They will usually give you pretty good even results.

-david

 

[panhandler1956]

I ran into this too and found somewhere that the bubbles need to be popped by lightly going over you epoxy with a foam brush. That helped my efforts abunch! I kept sanding away all the epoxy trying to get ride of the bubble craters - not fun and non-value-added!

 

[n8zg]

Squeege

I'd suggest you avoid the roller and use a squeege to spread the epoxy. An old credit card or similar works great for forcing the epoxy into pinholes and leaving minimum build-up.

Squeege on a coat, clean up the tools and let it set. While it's still tacky, squeege on a second coat. Then a third coat. Block-sand after the whole thing is fully cured.

If you find air bubbles in the epoxy while it's still wet, grab your favorite gas torch and just brush the flame over the bubbles. They'll pop and the epoxy will flow out to fill the void. I didn't believe it either - try it...

 

[mlwynn]

Getting a smooth finish

I'm with Neal on this. Use a squeege or old credit card. Push really hard to get the epoxy in all the little holes and remove all the excess. Sand to finish. After that, a light coat of primer and sand with a long block will show you the high and low spots. The inside of the skirts is a great place to practice for the outside of the skirts, cowl, etc.

The really nice thing about fiberglass is that you can screw up multiple times and just keep re-doing it.

Regards,

Michael Wynn
RV 8 Finishing
San Ramon, CA

 

[krwalsh]

Bubbles

As others have said, the roller is causing the bubbles. Get rid of it in favor of last year's EAA, AOPA, etc card. Or use waxed card stock. They come in packs of 52, and I hear you can use them to play games as well.

The last bit of advice is to get a hair dryer. Heat up the epoxy after you've spread it on and it will flow much better. 62F is too cold. get the epoxy up to 90F or so and it'll move for you. I was doing layups in the hangar this weekend and it was 42F. I couldn't wet out anything. Add heat, and everything went nice and smooth.

 

[DanH]

I have read DanH tips and those have been a big help.

Glad to hear it, but.....I do not thin epoxy and I already regret posting a picture with a roller in it.

Squeege the straight, unthinned epoxy into the surface. The nappy roller was merely an experiment to remove squeegee marks prior to cure and provide an even orange peel surface as a nice sanding guide.

62F is too cold for epoxy work. It just makes everything difficult or slow.

 

[jferraro17]

Mike--

I've been keeping every key card from my layovers for the last two years...they make a great squeege for what you're doing!

Joe