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May 07, 2012, 05:29 PM
Foam flogger
Hmmm...I have lots of straws. Also have some old CF rods lying around, think that might work? Probably be hard to get teeth into them though.
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May 07, 2012, 05:34 PM
Do it AGAIN! This time BETTER!
ThermalThief's Avatar
Quote:
Originally Posted by Belem
Anyone have tool suggestions for the servo channels as I don't have a small brass tube lying around my garage.
Finally started my build yesterday. Took the plunge and cut out the servo pockets. After that nothing should seem scary. ;D
I hotwire all my channels. GIves a nice smooth wall for feeding leads through.
May 14, 2012, 08:32 AM
What goes up, must come down..
ZeroPitch's Avatar

Wing Balancing


Feels like a stupid question, but how do I balance the wings? My TS1.0 wings are unbalanced by quite a few grams on the wrong side (throwing peg side is way heavy and I haven't even put the peg in yet).

Usually, I drill a hole in the tip on the CG line and drop in a bit of lead/epoxy then cover with monocote. But, this is my first bagged wing and it's pretty darn thin. Don't want to weaken it, disrupt the airfoil, or worse have a big ugly patch visible ;-)

Suggestions?

Jay
May 14, 2012, 09:05 AM
Registered User
Just go fly, no need to worry about lateral balance.
May 14, 2012, 12:53 PM
What goes up, must come down..
ZeroPitch's Avatar
Quote:
Originally Posted by mndlg
Just go fly, no need to worry about lateral balance.
Um, my experience is way different than that on several airplanes & gliders.

It's totally impossible to trim a model for straight and level flight at different speeds when the lateral balance is out. At one speed, wings will stay level. Flip to a different flight mode, or go into a dive, and the model will roll.

That's because the ailerons must have a slight bit of trim to counter the weight of the heaver wing at one speed, but at a faster or slower speed the balance will change.

Still looking for good ideas on fixing this up :-)

Jay
May 14, 2012, 01:53 PM
Registered User
Jay:

Your original idea sounded good to me.

Other ideas (not mine - from another thread on the same subject): a nail of the appropriate weight, in the end. Tungsten rod, in the end. Coins. Bigger weights, closer in (where the wing is thicker). And so forth.

Whatever you put in the foam will not hurt a thing, especially if it goes in with epoxy or foam-safe CA. That's one of the beauties of a foam wing.

And I must add this: while balancing laterally does make sense, I have never done it.

Good luck!

Yours, Greg
May 14, 2012, 02:19 PM
Charles Martin
BavarianCharles's Avatar
Quote:
Originally Posted by ZeroPitch
Feels like a stupid question, but how do I balance the wings? Suggestions?

Jay
Get some lead tape from a golf shop and use it to experiment with CG and lateral balance. It's sticky enough to not fly off your wingtip during launch! Alternate a 2 inch strip between wingtips and see if you can detect a change.

IMHO, there's no need for lateral balance. In an almost-perfect world, maybe, but not by strapping a chunk of weight to a wingtip. Matching the loading of the 2 panels (Weight/Area) and Moments of Inertia would require a lot more work. The panels would also have to be geometrically close to perfect. No warps.

May 14, 2012, 05:08 PM
Chuck it and see!
Wing-span's Avatar
[QUOTE

IMHO, there's no need for lateral balance. In an almost-perfect world, maybe, but not by strapping a chunk of weight to a wingtip. Matching the loading of the 2 panels (Weight/Area) and Moments of Inertia would require a lot more work. The panels would also have to be geometrically close to perfect. No warps.

[/QUOTE]

There is nothing wrong with trying to be perfect though, is there? (opinion respected)
May 14, 2012, 05:40 PM
Charles Martin
BavarianCharles's Avatar
Quote:
Originally Posted by Wing-span
Quote:

IMHO, there's no need for lateral balance. In an almost-perfect world, maybe, but not by strapping a chunk of weight to a wingtip. Matching the loading of the 2 panels (Weight/Area) and Moments of Inertia would require a lot more work. The panels would also have to be geometrically close to perfect. No warps.

There is nothing wrong with trying to be perfect though, is there? (opinion respected)
It's a noble goal, but I just go for 90% and move on. Love to build and tinker, but should spend more time flying to become a 90% Joe Wurts.

May 14, 2012, 06:09 PM
What goes up, must come down..
ZeroPitch's Avatar
Quote:
Originally Posted by Wing-span
Quote:

IMHO, there's no need for lateral balance. In an almost-perfect world, maybe, but not by strapping a chunk of weight to a wingtip. Matching the loading of the 2 panels (Weight/Area) and Moments of Inertia would require a lot more work. The panels would also have to be geometrically close to perfect. No warps.

There is nothing wrong with trying to be perfect though, is there? (opinion respected)
Not reaching for perfection here... like I said, it was a real problem and an annoyance for me on several power planes, floaters, and slope ships... so now I just always balance the wings during the build.

Jay
May 14, 2012, 06:17 PM
What goes up, must come down..
ZeroPitch's Avatar
Quote:
Originally Posted by BavarianCharles
Matching the loading of the 2 panels (Weight/Area) and Moments of Inertia would require a lot more work. The panels would also have to be geometrically close to perfect. No warps.

Weight/Area isn't balanced if the wings are not balanced. And is if they are. Simple.

Moments of Inertia might cause slightly odd roll behavior, but I seriously doubt anyone could detect a difference measured in single digit percentage of overall weight (a few grams).

Warps can be a problem if bad (mostly causing bad stall behavior), but at least they are fairly static regardless of airspeed and don't generally require constant trim changes.

Out of balance wings, in my experience, do. I hate to fiddle with trims once I get them set :-)

If your experience says different... hey, more power to you.
May 14, 2012, 06:37 PM
Will fly for food
davidjensen's Avatar
I usually take about 1/2 of the imballance out. I'll add some peal and stick color on the opposite wing tip and sometimes place some strip lead into the gap between the skins at the hinge line. I never add more than 2 to 3 grams.
May 15, 2012, 01:55 PM
Registered User
Neil Stainton's Avatar
Quote:
Originally Posted by BavarianCharles
IMHO, there's no need for lateral balance. In an almost-perfect world, maybe, but not by strapping a chunk of weight to a wingtip. Matching the loading of the 2 panels (Weight/Area) and Moments of Inertia would require a lot more work.
IMO lateral balancing (or at least halving the imbalance) by adding weight to the wing tip is worthwhile. Trying to trim the plane for all speeds is impossible with a badly out of lateral balance plane.

OTOH there is no need whatsoever to try to match the moments of inertia of the wings (and tail?? ha ha). Unlike a helicopter main rotor a DLG is rigid, and it will rotate about the CG as a solid body, irrespective of the moments imparted by each of the wings (and tail).

Neil.
May 25, 2012, 05:45 PM
Foam flogger
Still moving along slowly on my build. Got the wings joined , servos in, etc and moving on to the tails. I have the original balsa with film version. Wondering about putting the film on and hinging. Do I cover then tape? Tape then cover? Just cover and use film as hinge? Any pointers on ironing it on? Will be my first time. Have a covering iron.
May 25, 2012, 07:09 PM
Registered User
Belem:

When I had film-covered tails, I used the covering for the hinge.

Assuming you're right-handed, cover the left side of the vertical tal and rudder as if one piece. Then, fold the rudder all the way over to the left, with a piece of thin cardboard separating it from the vertical tail. Cover the right side in one piece, straighten it out, and done!

You can cover the two separately, and use Scotch tape as a hinge, on the left side only (again, assuming you're right-handed).

Do the horizontal tail the same way.

Yours, Greg


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