Composite Repair Supplies and Methods
 

I fly slope and jets. My airplanes are composite. Breaking is part of life and a good reason to take up golf.
I'm horrible at repairs but what choice do I have? There is almost no difference between my broken fuselage repair and a lawn sprinkler line repair. I add weight and make it ugly.

What's a list of materials to keep on hand to fix fuselages and wings? I have some super fine. light carbon vail that is hard to work with. My next sized material is thick fiberglass cloth. Should I get the West systems resin instead of tube epoxy?

I keep in stock: 4:1 Laminating Epoxy Brand FGCI out of St. Petersburg - less thick then West, urethane reducer or MEK to mix into epoxy for thinning application, 1 oz mixing cups- 4:1 epoxy needs exact mix., horse/pig hair epoxy acid brushes, several different weight of fiberglass from Thayercraft, Nitrile gloves, popsicle sticks, wax & grease remover-cleaner, Microballoons, several different grits of black wet sandpaper - 220 to 2000, lots of elbow grease, drinks and Medical marijuana to help keep it entertaining and for artistic interpretation of the project. 😎 Plus for the sore arm from sanding. Foam sheeting to lay on the table while sanding.

Thanks for the shopping list. I do have some of it already, but I my stock of marijuana runs out too fast...

I am a horrible repair guy, my results are solid but look like plumbing repairs. This fuselage broke in the front and behind the wing due to a vertical landing. I over-sanded the rear break and wrapped with three layers of a very thin carbon fabric. It is all I had. It is difficult to work with, some of it lifted when I was plying it and a smashed it down, now if has a marble look. I added about an 1/8" thickness, mostly resin because the carbon is only 0.005" thick.
The front was busted and a put a layer of kevlar inside it. I sometimes do this to gliders while building to make them stronger. It is solid but the outside is ugly.
Next time I break a nice airplane - I am hiring a repair guy.
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You just need more elbow action. To repair something like your break, I would use thin CA to put the pieces back in place. The I would have used 1.5 oz fiberglass cloth over it, wet sand it with 220. Then cover it with .75oz fiberglass sanding with 500 wet. Your just half way there. I like wet sanding, because it eliminates the dust, so that it can be accomplished indoors. The laminating epoxy thinned with MEK or urethane reducer will flow on, rather than goop on. Brush the area first with the epoxy mix, lay the fiberglass over it while wet, and brush it out with the damp brush. No cards or scraper to push the resin around.
Here's a picture of my latest repair after it was on fire. I bought it from a buddy who wrecked it, but couldn't repair it.
420 and some good tunes makes it more enjoyable

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This is a SM 1/5th F16. He had a flame out at low altitude flying high alpha. The fins went through the bottom opening to the still hot thrust tube. It caught the grass on fire.
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Big hole!
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Started with CA what parts were salvageable. Then used fiberglass sheeting that I made on a glass table.
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Lots of layers of Microballoons and heavy fiberglass. I sanded half away of what I applied
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Last fiberglass layer was with .75 oz fiberglass. This is for a better finish and an easier weave for the primer to fill.
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Finished. You can't tell. Still have to mount the fins.