Hi - hoping someone has been through the same thing and can maybe help me.

A day away from taking my Avistar, my first ever plane, for its maiden flight, I noticed that the ailerons appeared to be putting a lot of strain on the servo. I checked and noticed a lot of CA build up on a few of the hinges (those one piece flimsy ones that come with the plane, and have to be wicked into place). So I tried to carefully scrape as much as I could off with the back of a scalpel blade, but I fear I've seriously weakened the hinges and rather want to replace the lot of 'em.

So I bought a little pack of Great Planes articulated plastic hinges which I intend to fit. But, I first have to remove all of the old CA, bits of hinge and gunk from the slots in the ailerons and the wings. And more importantly, I need to remove the ailerons from the little metal pins they were epoxied to, without breaking them, or the wings, or anything else important.

Ay ideas on how to do this while doing the least possible harm? I would hugely appreciate a step by step from anyone out there.

I'm actually very near writing this plane off to practice and starting again from scratch!

Please help.

The normal method to rehinge is to cut off the old hinges whatever type they were and sand the stub smooth then cut new slots near them on one side or the other.

It sounds as though your original CA hinges were done with something other than thin Ca. If that is the case only thin CA should be used on CA type hinges.

If the wing is a single servo aileron set up with torque rods then after cutting all the hinges, grasp the aileron around where the torque rod pin is epoxied to the aileron and rotate the aileron around the pin back and forth. This will usually pop the epoxie or CA and allow the aileron to be removed.

John

Agree with John, cut the hinges with a sharp blade. Cut new slots beside the original for the new hinges. The Great Plnes hinges are much thicker than the CA hinges and trying to cut the wood hardened with the original adhesive will just cause trouble trying to keep it centered. To be honest removing the aileron from the little metal pin (torque rod) has some risk associated with it but there is really only one way to do it. Cut the hinges and then gently twist the aileron back and forth while pulling, eventually the glue or the wood will break and the aileron will come off the torque rod.
Cut new slots for the hinges, use sand paper and clean the torque rods, test fit everything without glue. use 30 minute epoxy and glue it together.
Use alcohol and paper towels to wipe the glue out of the hinge line, a little vasaline will help keep the epoxy out of the hinge too.
Good luck.

I've been told or read somewhere that making a line across the midpoint of the new hinge (where the gap will be) with a regular crayon will block the CA. The CA will flow to that point but not past it leaving the hinge flexible at that point. I've tried it on loose hinges just to experiment and it seems to work but I've not tried it in a plane. It may be about 99% BS.

If you are patient you could try debonder and let is soak for some time,then try to pull the ailerons off gently and remove the hinge from its slot.If you are lucky the slot can be reused with the new hinges.

If you glued the torque rods to the ailerons using epoxy, try a heat gun to heat the area. Sometimes this is effective in softening the glue and making the removal easier. If you used CA here, it should be easy to break the bond and pull them out.

DO NOT, I REPEAT, DO NOT USE THE SAME SLOT FOR NEW HINGES !!!!

The CA soaks into the wood. This is how the bond between the hinge and the wood is formed. The wood in the slot is already soaked/filled with CA. No more will penetrate the wood. Reusing the same slots is ASKING for a control surface failure.

Cut new slots along side the original slots and install the new hinges in the new slots. This will allow the CA (or epoxy if using Klett [nylon, pinned] hinges ) to penetrate into the wood for a proper, secure bond of the hinge to the wood.

What he said. Even if you plan on using different hinges you won't be able to get a good bond with any other adhesive. Even wood glue and epoxy needs to soak into the pours of the wood in order to make a good bond. The CA from the old hinges will have sealed the wood and the new adhesives won't be able to get a good bond in the old slot. Your best bet is going to be to simply cut a new slot for the new hinges.

Ken