763ersma27

Are makeing or using monocoat to hindge an airplane rudder, elevator and etc.. safe? what are the + and - of doing this..

Note : aircarft is a slow and low trainer.

Kaos1964

My Feedback: (12)

Just my opinion and I'm sure you'll get others, but I'd only do this on a 1/2A (.049-ish) size plane at the most. For a "normal" (.40 and up) trainer, I'd use something a bit more solid, like Robart hinge points or even CA hinges.

Hope this helps - can you give details as to the size of the trainer you're talking about?

Regards,

Bob

Mr67Stang

Kaos1964 is right on here. Monocoat hinging is nice because it seals the hinge gap but monocoat will eventually stress crack from folding it back and forth (So will CA hinges) Pinned hinges are the longest lasting I believe. So How big/small is this model?

763ersma27

Im unsure how to tell the size, Its a Hanger 9 Cub with a 80 inch wing span. I have CA Higes on everything but the Rudder, the rudder broke, and was fixed with monocoat hinges..

Mr67Stang

I wouldn't use monocoat hinges on a plane that size and the Cub is very dependant on it's rudder for TO and landing.

Dr1Driver

Do not use Monokote hinges on a plane that size. They are only suitable for a 1/2A model.

CA hinges are safe if properly installed. I've used them for years and had one in-flight failure on the elevator of my 1/4 Fokker Dr.1.. I feel this failure was brought on by several hard sideways hits the elevator took while transporting. I would, and will, use them again. Pinned hinges are also good, and I prefer Robarts there.

CA Hinge Installation

There are several rules to follow for an easy, correct CA hinge installation. These rules are good for hinges from different manufacturers, including Great Planes and Radio South. I’ve used them on many planes from pylon racers to Unlimited class Fun Fly planes to even a giant scale Stinger (the 1/4 scale size hinges).

Here we go:

Use a #11 blade to cut the slots.
Cut only once per side/per hinge.
Use only thin CA.
Do not double the hinges.
Do not use “kicker”.
Install after covering.

1. Slot the wood pieces (using the #11 blade), install the hinges, and mount the control surface. Gently push the pieces together.
2. Flex the control surface both ways for the maximum amount of travel you expect to use. This will automatically create the proper hinge line gap.
3. Slowly drop 2-3 drops of CA on each hinge at the hinge line on one side only. If any CA puddles in the hinge line, blot it with a paper towel.
4. When that is dry, apply 2-3 drops of CA to the other side of each hinge.
5. When both sides are dry, flex the control surface both ways.

That’s it! The wood will pull out before the hinge will let go. The surface will tend to stay centered and will not flop around. This will help prevent flutter.

Dr.1

Stripes

My Feedback: (19)

I have use them on numerous 40 sized models including pylon racers. Never had a failure. That said, I now use the CA hinges because I felt that there was an inherent looseness in the MK hinges. Over time they seem to stretch a bit and the control surface can be induced to flex forward and aft.

Trollmaster

They do this on sailplanes and such. I would not do this ona plane much more than that of the trainer size.

Rodney

I have used monocoat (also Solartex, Ultracote etc.) hinges on many very large models, even quarter scale. Properly done, they are as reliable as any other type hinge, probably better than most. This is when you instal them like baseball stitches similar to the way the old cloth hinges were installed on U-control models many years ago. I have one Phaeton 90 with a Quadra 72 that has been using this type hinge on all surfaces for well over 12 years and probably thousands of flights with never a hinge failure.

763ersma27

Thanks for all the help, good too see different anwsers.

763ersma27

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