The EPO foam hinges are weak : repetitive mechanical movements of the surfaces end up breaking the very thin EPO foam fixing them.
Here a video of a crash we had because of the loss of the left aileron in mid flight at 30 m altitude, and how I made repairs and reinforcements on it afterwards.
I would advise to reinforce the hinges right from the initial build to avoid any accidents; this is what I will do from now on having learned it the hard way...
Thank's Hugues for nice video, It's very usefull for non english speakers like me when you write explanation, easier to understand ;)
I have to glue one aileron that a friend cuts by accident during laminating process, I repair with tape but I don't like, Im going to try your tecnique, a pilot recommend me to glue with CA glue but UHU looks easier and more flex.
My tips: I always use the 3M tape when the airplane is new, If I don't find it I use cirugical tape (an Rc pilot and doctor recommend to me) It's work well too.
I use hair dryer to straighten with carefull not to hot in excess.
If parts to glue are not perfect I use Gorilla glue, It's extraordinary to fill little holes.
As worse pilot, better expert in repairs ;)
Thx Cala. Yes the surgical tape is exactly the same as 3M hinge tape. In fact 3M never did that tape for RC but for medical stuff.
I advise you not to use CA as it is too brittle. UHU POR is the best glue I have found for foam (EPO/EPP/etc) that remains flexible. It is also thick so you can fill small holes with it. On the contrary, to fix cracks, it is better to use really thin CA so that it penetrates deep enough.
Learning from that incident, I will also, from now on, reinforce all of the control surfaces hinges with the same method. (so I can keep crashing without stress:)
+1 for UHU POR
I have a product that's looks similar, suprabond plastic. You know it? I never used for this task, I'm going to try to find that UHU, I didn't know about it, It's look very apropiate to foam, I'm using Unipox for foam to build but You have to put in only one side and wait one day to well dry.
In resume: you put first the glue on the two surfaces with a pencil, then the paint tape, then you paint with extra glue and finally the reinforced tape, It's correct? I'm going to try with my aileron, Thank's.
...you remember me that stabilizer don't have tape, perhaps you save me from a crash with your post ;)
I do not know suprabond. UHU is a glue from Germany, it might be difficult to find. If you need it, I can send some to you.
In summary, I first reglue the aileron with UHU glue on its original thin hinge. I let dry. After that I spread some glue on the surfaces around the hinge and then I apply the tape along the hinge. Once one side is done, I do the other side.
Many thank's Hugues, I investigate on web and UHU por exist in my country :D I'm going to try to find in my city I'm shure I can find it, today is holiday here and no good day to fly so I'm inspecting all movement surfaces ....in case ;)
Good idea. It is winter now here and a good time for building/ repairing stuff as we can't fly much.
Here we are waiting summer, time to flyyyy!! :D
You can also glue in hinges. They are found in most hobby stores which sell planes and parts. They last long.
Thank's Dimitry, I bougth them but I didn't try, at the end I found uhu por and follow Hugues video and nice results :) I have them in a rudder and works well too.
Hinges give the problem that they result in a space gap between the surface and the wing , that degrades strongly the efficiency. Another issue is hinges are not easy to fix reliably on thin EPO surfaces.
Some people like it though and it works too.
Waw, this is really cool. I had this worry in mind about possible incident with the way those hinges looked, I was intending to do something similar on mine plane, now you have made me more confident, I'm going to do exactly that. Thanks for the instruction, very useful.