Filling fiberglass tips

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RVNewsletter
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Filling fiberglass tips

Post by RVNewsletter »

Before I get comfortable working on the canopy windscreen fairing, I thought I'd mess with the empennage and VS tips, which have to be closed.

Van's recommends one of two methods. One is stick some Styrofoam in there, put some cloth in, let cure, then chip out the Styrofoam and lay in some more cloth inside.

Is that what most people do?

Here's the reason I ask:

I stuck the foam in, added a layer of BID. After it cured, chipped out the Styrofoam, mixed up some epoxy and filler and smoothed it over.

I'm thinking that that should be enough. Do I really need to add another layer of glass inside? Is this because there really isn't that much contact between the filler and glass and the tip itself?

weezbad
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Post by weezbad »

yes i would add the layer, and the reason you stated is why.

i put clear tape over the opening and laid cloth (2-3 layers) in the tip providing a fair amount of contact (3/8s to 1/2) between the tip and cloth. i installed the tip wet and put in a popsicle stick to get the radius started for the counterweight to swing by.i used flox to fill in any divets. this is an area where you really dont want the potential for something to let go and cause a jam. ive seen folks fill with bondo and that somewhat concerns me.
william....don't let it beat you down, you are stronger than you think.

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newtech
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Re: Filling fiberglass tips

Post by newtech »

RVNewsletter wrote:Before I get comfortable working on the canopy windscreen fairing, I thought I'd mess with the empennage and VS tips, which have to be closed.

Van's recommends one of two methods. One is stick some Styrofoam in there, put some cloth in, let cure, then chip out the Styrofoam and lay in some more cloth inside.

Is that what most people do?
My technique is not original thinking, it is how layups like this are done on the original Europa and many other wet layup composite projects. Using 40 grit sandpaper rough up the inside edge of the fiberglass tip for about 1/2". make a 1/2" thick foam rib to fit in the tip opening. using a sanding block sand a 45 degree bevel around the outside edge of the foam rib. Epoxy the rib into the tip using five minute epoxy. when cured mix up some epoxy/flox and fill the trough around the edge of the rib that was left by sanding off the 45 degree edge. Cover the rib and flox with peelply and squeege it smooth. Since flox is structural we have created a nice bonding area around the edge of the foam rib. After the flox is cured layup a couple layers of 9 oz. glass on the foam rib. Don't wory about trying to wrap the glass around the edge of the tip just let it extend straight out. After it is cured sand it flush with the edge of the tip. Remember peelply is you friend, use it on all layups.

Doing it this way you don't have to worry about removing the foam rib or doing any interior layups.
Steve Eberhart, W9BOJ
3EV - Evansville, IN
Where is Steve and the Sky Terrier
RV-7A Slider, O-360 A1A, Catto 3 blade, New Panel with Garmin G3X and 696, Icom A210, Bionics APRS. FLYING since June 24, 2009

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RVNewsletter
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Post by RVNewsletter »

Cool. Can someone upload a pix of their enclosed and installed emp tip... shot from behind with the elevator counterbalanced moved up or town? I just want to check something.

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