Expert advice/opinion needed

Would a small gap make

Aerodynamically, a small gap will make a difference. It is up to you to decide if the difference matters. I am a pilot. Haven't flown my first RC yet but...stuff is on order.

Many full scale airplanes have a gap between the ailerons and wing. Several planes have an STC approved change to add gap seals to improve performance. Typically you might gain 1-2 knots and improve roll performance a bit. I don't recall what the mfgers claim.

It just depends on how big the gap is whether it is safe or not.

Carl

No, it won't make a difference (unless you can drive a car through it) but there are some who will say differently. (Thank God for our differences.) What will make a difference is pinning your hinges. All hinges should be pinned despite what some folks will say. You are proof of that. This can be done a number of ways: Drill some small holes through the wing and hinge and insert a round toothpick. A drop of CA will secure it. Cut it off flush. Do the same on the aileron side of the hinge. Pin all the rest of the hinges while you are at it. You can also do it with a straight pin. Just push the pin through and cut it off. With a bit of practise you can cut it a bit short so it disapears completely into the wood. In my 50 + years of modelling I can't tell you how many control surfaces I have seen part with the 'plane because the hinges were not secure. You were lucky. You got it down in one piece. Many are not so lucky.

Gord Schindler MAAC6694

Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:

It may or may not make a difference. How fast are you going to fly the plane ? How big is the gap ? The faster you fly the more difference it will make. If you get up around 90 - 100 mph there is a very real possibility of the turbulence through the gap causing flutter and ripping an aileron off. Of course the variables are how large is the gap and what speed you are flying at. A larger gap at slower speeds can cause the same problems a smaller gap at high speeds.

I would suggest sealing the gap with some matching color film on the underside of the wing. It will eliminate the problem and I doubt anyone will even notice the sealing.

Hi Gord!

Looks like we both went to the same school.

Except on indoor foamies....I pin all my hinges as well....

I learned this this about 40 years ago...

The lesson lasted ..oh...about 6-7 seconds...

The homework assignment took about 3 wks.. :(

Cheers!

Dave

I used to use VWR Scientific's lab tape (polyester base) for sealing ailerons and other flying surfaces. It worked great and it held up well in the model fuel environment. I'll bet it is similar to what you are recommending.

Ed Cregger

Many thanks for all the advice. First of all, I have just measured the gap and it approx 1/8th of an inch so is this classed as large/excessive? I have decided to follow the advice and put a strip of film on the underside as it's al the same colour there anyway AND I have already pinned the new hinges. it's a petty that all kits don't come like the 2 Seagull models I have. Both of them came with hinges fitted (good quality) and they were already pinned.

cheers, Len

It also delends on whether the gap is used as a slot to keep airflow over highly deflected ailerons.

I have seen gaps in trainer ailerons have quite a large effect on roll authority. The way most models are designed, no gap is better.

There is wee, not so wee, and FRIGGIN HUGE. That gap is of the latter!

Well it ain't any more as I have taken advice from this thread and put covering over the underneath of the 'gap'. I am also thinking of doing the same on the top as well so gap no more! I was very worried about using the 'biscuit hinges' supplied as I really didn't think they would stand the stress, hence the bigger pinned hinges. Obviously I should have recessed then into the wing/aileron but they are stuck so fast now that covering the gap is the only real solution. Lesson learnt! (the hard way as usual!) Thanks for all the advice on this one.

cheers, Len

Who Hoo!!!

That will probably affect roll response of the aircraft..

Dave