What do all of you use on the nylon cover down the center of a wing? I'm building a eagle 2 trainer wing and it says to use CA glue. Ive heard some use epoxy? Which one would be smoother/stronger and would sand better?

Thanks in advance!

Either will work.

I feel more comfortable with epoxy.

Enjoy,

Jim

hey. sorry to jump in, but is that nylon cover really necessary? i cant see a significant difference in strength between using and not using it
just wondering

i use it, its just a wider bonding area between the two wing halves and i use 8 hrs epoxy but before it set i smooth it out with my finger dipped in alcohol.

joeypm,
You can use either to set the fiberglass strip to the wing. Having used both CA and epoxy I can say from experience I prefer to use epoxy. With CA you have very little time to make any adjustments to how the fiberglass is laying on the wing, if there are any imperfections they will be set and made permanent immediately. Another thing I don't like about CA is the fumes. When putting the CA on to the fiberglass it is going to put out some serious fumes that are going to be really harsh on your lungs if you inhale them, and will be bad for the moist tissue in your eyes and nose. The last thing I dislike about the CA is the plain cost of doing this strip with CA. CA isn't cheap.

I like using epoxy for several reasons, the biggest is the level of finish you get out of using epoxy. Using 30 minute epoxy (or even better use finishing resin) you have plenty of time to produce a very high quality product. After you mix your epoxy use a disposable epoxy brush and "paint" epoxy into the area where the fiberglass with go. Now put down the fiberglass in position on the wing over the epoxy you just brushed on. Using the brush or your fingers (trust me, rubber gloves are a great investment in modeling) work the fiberglass into the epoxy you already have down. You want the weave of the fiberglass to be "wet" from the epoxy. If need be you can use the brush to put down a little bit more epoxy. After you have the weave wet you can use an old credit card, old playing card, or a anything similar to these to squeegee the epoxy out of the tape. You want to work out as much as you can from the tape. After you are happy with the tape wipe up any excess epoxy and then set the wing aside to dry. If you take a look at this post in my Pay It Forward LT-40 Build it talks about putting down this strip. There are also some good pictures that accompany the text so you can see how it's done. You can find this here [link]http://www.rcuniverse.com/forum/m_3439708/mpage_9/key_/tm.htm#3529027[/link]

Andrew,
Actually, yes this strip is very important to the structural strength of the wing. Builders and kit manufacturers have been using this for strength in their wings for decades. The keep using it not out of habit but because it works. If the instructions call for it you definitely need to put it in. In fact, I have built planes that didn't call for it but I went ahead and put it in anyway because it does make the wing stronger.

Hope this helps

Ken

I have found that "finishing resin" works well. It is an epoxy, but thinner in consistency, which makes it easy to brush and smooth out with an old credit card or similar. Having said that, I wouldn't go out and buy the finishing resin for a single application. 6 or 30 minute epoxy works almost as well IMO.

DaveB

Thanks all..... I do have some 60 minute epoxy will that work or is that to slow set up time.......

I prefer epoxy and here is a tip that will save you many hours of sanding. After putting on the nylon (or fiberglass) and spreading the epoxy, take some Saran Wrap (like used in the kitchen) and put it over the whole area that has been epoxied down. Smooth it out with your fingers and then let it set up. When you now remove the Saran Wrap after the epoxy has thoughly cured you will have a surface glass smooth and (if you smoothed out the edges) no dicernable ridges to have to sand out. Make sure you smooth it out though as any wrinkles will show up prominently.

The slow drying epoxy will be fine.

Do one side of the wing at a time and let it set before doing the other side.

Enjoy,

Jim

Thanks again to all. I really appreiciate the feed back.....

Hi!
Never ever use Ca glue to fasten 25g ..or heavier glassfiber to any surface particularly not joining the wing halves[:@].
To do this you should use either polyester resin or epoxy finishing resin!

Regards!
Jan K
Sweden