Hinge line taping - one or both sides?

[Dennis Toth]

Just out curiosity has anyone found any advantage to taping both sides of the hinge lines? I have always just stuck in on the bottom but was wondering if the tape would aid in smooth airflow to the control surface is both side were tape. Any thoughts?

Best,   DennisT

[Dave_Trible]

I doubt you would find any noticeable or measurable difference in taping both sides.  If anything it would just make the controls more stiff to move.  The main point of the seals (to my knowledge) is to prevent air blow through at the hinge line which I believe promotes flow separation on the top-side.  As log as a single seal is blocking this blow through I would think the goal has been achieved.  I'm not sure it helps or is necessary on every airplane but it doesn't hurt so I do it universally to most everything.  You can allow a little more space between surfaces to get a large range of free travel and yet still get a working seal.

Dave

[Tom McClain]

Add to 2005 VSC, Bob Whitely taped the hinge lines on my quasar. He only did the bottom side. The difference was phenomenal.  That is all that is needed. I use crystal clear cellophane tape, and I use that on all of my ships.

[BillP]

Monocote is the only "tape" i've used and applied on both side...no hinges, just the monocote...Worked fine on a 60 rc ship.

[Dennis Adamisin]

Taping one side yields the functional improvement - for awhile. However fuel will soften the glue and tape in the gap will attract dirt, grass clippings, small insects & other bad stuff.  Fuel also can pool there, loosening the tape the seals will "blow out" when ever they get the urge and never when its convenient.

Tape both sides adds longevity & keeps it cleaner.  Tape-to-tape surface also mimics a full span hinge helping control surfaces to resist bowing - meaning the controls are less like to want to force themselves back to neutral; probably more important on thin surfaces.

[fred cesquim]

do a gap free hinge installation benefit from it?

[Steve Helmick]

Tape the bottom side. If you refuse, you will probably struggle with getting same sized inside/outsides and consistent control responses. I've always found good tape seals will last a full season or more, but I don't get to fly 1,000 flights a season.  Steve

[BillP]

One side helps with flutter on narrow flaps and not so much on wide ones.

[Gary Dowler]

Monocote is the only "tape" i've used and applied on both side...no hinges, just the monocote...Worked fine on a 60 rc ship.

You attached the elevator and flaps with just monocoat?

Gary

[Ken Culbertson]

You attached the elevator and flaps with just monocoat?

Gary

Makes a great hinge.  RC has used it for years on ailerons.  Not as easy on CL since we hinge on the CL but it still works.

Ken

[Dennis Adamisin]

You attached the elevator and flaps with just monocoat?

Gary

Absolutely.  Like Ken said this is old news in RC, either of two methods:

1. Use an over/under arrangement, mimicking what we've been doing with cloth hinges forever.  Absolutely the best hinges for small stuff and/or thin surfaces.

2. Use with CA Hinges.  For this I use the CA hinge cut in half, and setting a 1/32" hinge gap.  "cote the movable surface first, covering through the hinge gap and to the TE edge.  Repeat on the other side making sure the 'cote comes together in the gap (glue side to glue side) thus forming a 100% full span hinge - extremely clean looking too.

I also 'cote between the hinges when using pinned hinges.  Reduces stress in the pinned hinges, though technically air can leak through the hinges themselves - I'm over it...

[BillP]

You attached the elevator and flaps with just monocoat?

Gary

Yep. 30+yrs ago but I never did it on the elevator.