Sealed Hinges

[Ken Culbertson]

Pardon my ignorance but I had never heard about sealing hinges until I started reading a lot of the comments here.  We never did that "back in the day" and I just assumed it meant getting the elevator and flaps close to the wing and stab.  Then I read one talking about using clear tape.  Huh?  Somebody please enlighten me.  Is there maybe a DYI video on Youtube.  I hate it when I don't know what I am talking about and there is so much we all just assume everybody knows!

Ken

[Tim Wescott]

I don't know about a video -- maybe there is, maybe not.

• Get some Scotch crystal clear tape (not the translucent stuff).
• Place the airplane upside down on your bench.
• Clean all the oil off of your hingeline.
• With the back edge of the surface (flap or elevator) down (as in toward the floor, not toward the wheels) as far as it'll go, apply the tape to the gap
• Make sure everything still moves freely
• Repeat for the rest of the plane

Lots of folks (like me!) only put tape between the hinges, because it's almost impossible not to induce some friction at the hinges.  But you lose a bit of sealing.  Six of one...

[Randy Cuberly]

Tim's description is a good one and certainly covers the application of the tape, very well.

I would add a couple of things, not to the application but to the preparation.  When building the airplane it is probably best to forego the previous tendency to get the control surfaces and the wing and stab surfaces extremely close together.  It actually aids the application and function of the tape, and reduces friction better to have a slight (maybe a 64th inch or so) gap between the mating surfaces.  The tape adds almost no friction and performs the sealing function very well

Also remember that a very free control system is absolutely necessary to precise control function and stability when trying to do the tricks we perform.

I would also add that I believe this to be as important in building a stunt plane as any other function performed.
If the hinge lines are "Leaky" it will never be possible to truly trim a stunt plane!

Randy Cuberly

[Paul Taylor]

There are a few Windy videos on YouTube where he seals the hinges. I think the Testarossa series has it and maybe the Tribute.

[Ken Culbertson]

Thanks guys.  Sometimes common knowledge ain't so common!  Just out of curiosity, about when did this start?  It is common practice in soaring to use the covering itself as a hinge but I have never seen it in CL.  Can't say that anymore can I.

Ken

[Brett Buck]

Pardon my ignorance but I had never heard about sealing hinges until I started reading a lot of the comments here.  We never did that "back in the day" and I just assumed it meant getting the elevator and flaps close to the wing and stab.  Then I read one talking about using clear tape.  Huh?  Somebody please enlighten me.  Is there maybe a DYI video on Youtube.  I hate it when I don't know what I am talking about and there is so much we all just assume everybody knows!

Ken

https://stunthanger.com/smf/stunt-design/hinge-options/msg99465/#msg99465

[Ken Culbertson]

I now have sealed hinges.  Thanks to the help I got here it only took about 30 min and it is hardly noticeable. There is a slight tendency for the controls to return to center if I go past 30 degrees on up.  I don't think this will be a problem in the air.  Now it is back to the bench to find out what else I don't know about the current state of the art.

Ken