I'm kind of a newbie at light weight glassing, so I'm not sure if repairing it is just adding too much weight...

From : Don Stackhouse

Not if it's done right. The repair method for the crunch in the leading edge depends on how big the crunch is. If it's very small and limited to just the immediate vicinity of the leading edge radius, just rub some epoxy ito it and smooth everything back into position while it sets. A piece of waxed paper wrapped around the repaired area can help hold everything smoothly in place while the epoxy cures.

For a larger area with more extensive mashing of the foam, it may be necessary to cut away the crumbled skin and foam, and fit a new piece of foam into the gap. Leave it oversize, then carefully carve and sand it to match the contour of the surrounding wing surface. Mask off the area with masking tape, about 3/8" outside the perimeter of the foam patch. Wet out some 1/2 or 3/4 ounce glass on a piece of waxed paper using thin epoxy (laminating epoxy such as West Systems is best, but the thin 30 minute epoxy will do fine as well), wipe a THIN swipe of epoxy onto the repair area of the wing (just enough so the surface is slightly damp, to ensure a good bond), then cover the foam patch plus about 1/4" all around it with a patch of the wet glass cloth. Carefully peel off the masking tape (pull it back flat over itself, not upward, so it doesn't pull the glass skin loose from the foam), then smooth a fresh, clean piece of waxed paper over the repair to keep everything flat and smooth until the epoxy is fully cured.

Once the epoxy is thoroughly cured, carefully peel off the waxed paper. You may need to touch up around the edges a little with some fine sandpaper, about 240 to 320 grit should be about right. Be careful not to sand too far and damage the glass patch or the glass skin around it, and don't dent the skin and foam with too much pressure. Nice fresh sandpaper and a LIGHT touch does the job!

A similar method will work with the tear in the trailing edge. Open it up a little, and work in some 30 minute epoxy into the break, then wipe off any excess that squeezes out when you work the gap closed again. If it's a really bad tear, you can put a patch of glass over the break, as described above.

If you have damage (including creases) in the spar caps, it gets a little trickier. Use your covering iron set on low heat (about 150-180 deg. F) to try to bring up any foam around the break that is mashed inward, work some 30 minute epoxy into the gap and keep the wing flat and straight while the epoxy cures. Sand the surface of the spar cap for about 3/4" all around the break, and mask off the area outside of that. If the area over the break/crease itself is not flat and smooth, use epoxy and microspheres to level it. It's important that the finished patch be free of kinks or ripples which would reduce its compressive strength.

Now cut a patch of carbon unidirectional cloth that is as wide as the spar cap and overlaps about 5/8" on each side of the break. Round the ends of the patch to reduce any stress concentrations. Wet out the carbon patch on a piece of waxed paper (be VERY careful to make sure the epoxy completely saturates the carbon!), wipe/squeegee off the excess epoxy, dampen the area around the repair with epoxy as described above, and rub the carbon patch in place on the wing (remember, the fibers should run SPANWISE!). Peel off the masking tape as before, then rub a fresh piece of waxed paper over the repair to hold everything flat and smooth while the patch cures. With a little sanding arond the edges (CAREFUL!) the finished repair will only be slightly ugly. ;-)

Once your repairs are done, be sure to check the washout of your wing. The outer panels should have about 1/16" to 3/32" washout, and it should be zero to 1/16" on the inboard panels. The washout on the left side and right side should be exactly equal. If the washout is off, use your covering iron (set at 150-180 as above) to reset it. The process is similar to the method used with built-up film-covered wings. Just twist the wing into the desired washout, run the iron all over the upper and lower surfaces in the region you're trying to re-twist, then hold the wing panel in that position for about 30-60 seconds while it cools. It should hold the new twist, if it doesn't then repeat the process. Be careful to keep the iron moving at all times, or you could overheat the foam under the skin, destroying your wing panel.

BTW, one of the unfortunate consequences of making the model so light (which is if you want it to fly well) Is that the wings do have more of a tendency to change their twist over time. Get in the habit of checking it regularly, and be especially suspicious of a twist problem if your model handles poorly. If you notice it's sluggish to respond to rudder inputs, tends to tip stall, tends to curve one way on launch, or just doesn't seem to perform well, there's a good chance that some wash-in crept into the wing. Fortunately, five minutes and an iron will fix it.

Good luck, I hope this helps, and please let me know if you have any more questions!

...The leading edge got pushed in and the trailing edge on one of the outer panels got a crease and a 1 inch tear... Is there any way to easily repair this, or can I just buy a new wing?

We do sell new wings for folks in your situation, but I'd bet yours can be repaired. It will gain a little weight, and won't be quite as pretty, but it should still fly just fine.

>My Spectre came out tail heavy, probably cuz I glassed the control >surfaces!

That would do that! A lot of folks leave them bare, or use just enough Varathane to seal and protect them from moisture.

Don Stackhouse
DJ Aerotech