As I posted in another thread a few days ago. The biggest issue with these repairs is surface area. Simply gluing or epoxying it doesn't provide much support. it needs something like a butterfly bandage.
I use dryer sheets. Its like a thin layer of fiberglass.
Step 1. Epoxy or JB weld the cracks making sure the frame is straight.
Step 2. Sand the high spots
Step 3. Mix epoxy and spread it thinly over cracked areas you repaired.
Step 4. Cut a used (it must be used) dryer sheet to fit the area you just put the epoxy.
Step 5. Push the dryer sheet into the wet epoxy and shape it to the curves.
Step 6. Decide how many layers you want to put on the affected area. 1 may be enough on a straight crack More may be needed where curves are.
Step 7. Let it dry, then you can sand it and paint it.
I would do the outside 1st then repeat on the inside of the frame. It may not look pretty but it will keep the solo flying. Or atleast give you a back up frame if needed.
The dryer sheet is super strong and surprisingly provides a lot of structure when covered in epoxy. You can also use backing that you get in the sewing department at Wal-Mart if you don't have dryer sheets.
I did a repair on a canoe during a float trip many years ago and the patch is still there. The canoe has been on many river trips since and has not failed.
I have used a product called fiberfix to fix 75 flag poles for our high school band and it worked well. They have released a product called fiber patch. I does everything I described above but is in a malleable patch. I am not sure how thick it is. The fiberfix roll was about 16th of an inch and in a roll. you can get it at Lowes. May be worth a look.
The nice thing about the dryer sheet is its light and strong. It is a little bit of work but it will work.