Vinyl Decals on Wing?

[GordonTarling]

What is people's considered opinion of vinyl decals on a wing? I've normally fought shy of using them on my gliders because of the possibility of them causing unwanted flying characteristics, or a deterioration in performance, but I see them being used on many more models lately, so the effects can't be too bad.

Just in case any doubts that they can affect performance, I can cite the case of an F5D pylon racer which flicked on launch every time until the decals were removed. :-) The same vinyl material is also often used in the form of a zig-zag strip along the leading edge as a turbulator.

My main reason for asking is that I want to apply some advertising decals to the wings of some of my gliders - they would be applied on top of the smooth film covering and located behind the spar position.

[BEC]

A racer that rolled over until they were removed? Wow!

As you may know I use such graphics on most of my planes (see pictures in Parkflyers, or my Big-T review). I do tend to have stuff on both wings.....

Here's a pic I've posted in another place today showing my smallest plane at the moment with vinyl on one wing and on the opposite elevon. It doesn't loop straight, but neither does anyone else's example of the plane that I know of. Something about uneven servo motion.....

[KOMET 44]

Gordon my friend does all my vinyl lettering for my planes.I use it on the bottom and the top of the wing.Go to the photo gallery,page three of the scale photos.Look for my Fokker Universal(blue/yellow) My friend uses the lightest vinyle he has in stock.I haven't seen any problems.good luck,stefanP

[leccyflyer]

Originally posted by GordonTarling
Just in case any doubts that they can affect performance, I can cite the case of an F5D pylon racer which flicked on launch every time until the decals were removed. :-)

They didn't say "Other Side Up" did they Gordon??

;)

Leccy

[GordonTarling]

Thanks for your replies chaps - guess it'll be OK to add them as long as I keep them reasonably symmetrical.

Brian - they didn't say 'other side up' - you're getting confused with the placard in a certain Irish airline's flight deck which says 'Land green side up'. :D

[Bill Glover]

Yes I heard the same story about an IC pylon racer (I used to race Sport 40).

As an aside, vinyl varies quite a lot. I use two types of white A4 stuff from Overlander and one is noticeably thicker than the other (but it's softer, and goes round slight compound curves easily ... which the thinner stuff doesn't).

On "high performance" models I only put stickers etc. on the wing towards the TE (well back past point of maximum thickness). On my IC pylon racers I didn't have anything on the wing except the race number (which was mandatory) :)

[Ian Dale]

I have used turbulators (from vinyl trim tape) and stickers on my Little Star E400 with no problems. Like Bill though the stickers are aft of the 50% chord point.

I vaguely remember reading about the pylon racer with the problem. But I think if memory serves me correctly the sticker had been applied OVER the turbulator and that this model had been explicitly designed to use turbulators.....

Cheers

Ian

[GordonTarling]

Bill - the vinyl I plan to use is 70 micron from the sign vinyl supplier that I normally use. It's one of the thinnest that they stock, so I'm sure it will be OK.

Ian - I only plan to add the decals behind the mainspar, so I'm fairly certain it won't upset the aerodynamics too much.

You'll certainly be hearing about it if I have a crash because of a decal or two! :)

[Bill Glover]

Originally posted by GordonTarling
You'll certainly be hearing about it if I have a crash because of a decal or two! :)

Make sure you put the same number on each wing so lateral balance isn't affected :D

That was definitely a joke btw. I haven't worried too much about lateral balance since I spent an afternoon flying a 100" model with a big block of lead screwed under one wingtip. I'd been doing aerial photography using a side-mounted pod with a heavy 35mm camera in it, and the lead block was a counterweight on the opposite wingtip. Forgot to remove it after I'd finished taking pics., and only noticed it was still there when I was putting the model back in the car at the end of the day. I'd been looping, rolling, spinning the model, doing stall turns, touch & gos, etc. etc. and no clue at all from the handling that the wing was massively unbalanced!

So balancing laterally is a good and correct thing to do, but nowhere near as essential as a lot of people think (IMO).


PS Gordon, is your website coming back or gone for good??

[GordonTarling]

Bill - lateral balance won't be affected, I'm sure. Interesting about the lead block - must try it sometime. :)

Website IS still there, it is the re-direction which is not working because I am transfering the domain name to another ISP.
Website can still be reached at - http://homepage.ntlworld.com/gordon.tarling/

The re-direction should be working again soon. In the meantime, I'm trying to get to grips with Netobjects fusion in order to give the website a much-needed overhaul.

[steve lewin]

I'm glad you mentioned your website Gordon, I'd been getting worried. Have you given up selling Megas or have they just not made it to the website yet ?

As for stickers I know they'd make no difference to me. My flying is such that I'd hardly notice a missing wing. I did actually fly an ARTF where the nasty sticky back plastic covering ripped away from the underside of 2 panels of a wing and I couldn't tell any real difference in the flight characteristics. I was so surprised that I took it back up again just to check that it really was flying o.k. (I know that wasn't really a good idea and I don't think I'll do it again but I was younger then ;)).

Steve

[GordonTarling]

Steve - Mega motors will be on the re-vamped website just as soon as I can get to grips with Fusion!

[Viper Pilot]

Gordon,

Aren't these products vinyl?? Don't you use your own products???

VP

P.S. I'm ordering some myself for Xmas. Stay tuned.