Go Back  RCU Forums > RC Airplanes > Composites Fabrication And Repair
Reload this Page >

Composite Repair Supplies and Methods

Notices
Composites Fabrication And Repair Carbon Fiber, Kevlar, Fiberglass and all the newest high tech composites

Composite Repair Supplies and Methods

Old 05-23-2021, 05:22 AM
  #1  
jvaliensi
Thread Starter
My Feedback: (1)
 
Join Date: Apr 2006
Location: northridge, CA
Posts: 345
Received 36 Likes on 28 Posts
Default 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?
Old 05-23-2021, 01:14 PM
  #2  
RCFlyerDan
My Feedback: (54)
 
RCFlyerDan's Avatar
 
Join Date: Apr 2002
Location: Cape Coral
Posts: 1,839
Received 12 Likes on 12 Posts
Default

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.
Old 05-24-2021, 05:56 AM
  #3  
jvaliensi
Thread Starter
My Feedback: (1)
 
Join Date: Apr 2006
Location: northridge, CA
Posts: 345
Received 36 Likes on 28 Posts
Default

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.




Old 05-24-2021, 08:16 AM
  #4  
RCFlyerDan
My Feedback: (54)
 
RCFlyerDan's Avatar
 
Join Date: Apr 2002
Location: Cape Coral
Posts: 1,839
Received 12 Likes on 12 Posts
Default

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


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.

Big hole!

Started with CA what parts were salvageable. Then used fiberglass sheeting that I made on a glass table.

Lots of layers of Microballoons and heavy fiberglass. I sanded half away of what I applied

Last fiberglass layer was with .75 oz fiberglass. This is for a better finish and an easier weave for the primer to fill.

Finished. You can't tell. Still have to mount the fins.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.