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Old Jan 02, 2012, 09:55 PM
NY Slope Dog
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Syracuse, NY
Joined Sep 2003
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Question
Bowman Sonic Replacement?

I've got a couple old Bowman Sonics still in service, but I understand L2 does not currently offer this plane (as they do the Scooter and JW models).

I like this plane for these reasons:
  • Great energy retention (recall this was Bowman's BEST precursor to the famed JW)
  • Excellent inverted performance. I taught myself continuous rolls with this plane.
  • Easy to build

I want to recommend a similar plane to my friends. Must be a 48" "zagi type" (ie no fuse).

All I know is that the Windrider Bee is NOT it. Nor is a Weasel. Both are great but not at the top of the niches I want most for this recommendation.

What would you recommend?
thanks,
Joe
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Old Jan 03, 2012, 03:34 AM
F3B
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Halfpipe? Good little model.
(or lj48 etc.)
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Old Jan 03, 2012, 08:31 AM
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Have you tried the Wing Warrior kits? Raider, Ridge Runner, or Slayer?
What's wrong with the Bee/BeEvo?
I've been looking for a Sonic kit for several years. Bill and Jason once mentioned they needed a commitment of 50 orders to do a limited release. I'm in for 3. Maybe we can start a waiting list.
Another option...I've heard the Sonic uses the same airfoil as a JW so you could sort of make a 48" Sonic with JW cores.
Here's an interesting pic of a couple of Bee cores laid over a JW wing. Hmmm.
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Old Jan 03, 2012, 11:51 AM
NY Slope Dog
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I haven't tried the "BeEvolution". Is it good inverted ?

The original Bee, while super for combat won't stay inverted very long without dumping speed.
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Old Jan 03, 2012, 12:12 PM
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Quote:
Originally Posted by Wind Junkie View Post
I haven't tried the "BeEvolution". Is it good inverted ?

The original Bee, while super for combat won't stay inverted very long without dumping speed.
My Bee flies inverted great. I've done whole combat sessions inverted, just for fun. Mine
does not dump speed. Where did you have your CG set?

The Beevo is not as well rounded of a plane and slows down quickly when you maneuver aggressively, and
will tip stall where the Bee does not. It is relatively quick though.

ian
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Old Jan 03, 2012, 12:23 PM
F3B
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it's a combat type wing that you are after?
If so then the halfpipe probably isn't the best tool.
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Old Jan 03, 2012, 12:34 PM
Confirmed Chronic
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Quote:
Originally Posted by Daemon View Post
My Bee flies inverted great. I've done whole combat sessions inverted, just for fun. Mine
does not dump speed. Where did you have your CG set?

ian
+1. My Bee flew inverted as well as any sloper I've ever had. Hands off. Nearly equal performance to upright. In fact, in my opinion, it's the best wing on the market.
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Old Jan 03, 2012, 12:42 PM
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BTW, if you're really set on the Sonic, I *think* the CS Jazz Xtreme is actually the same plane.
http://www.flycs.com/index.php?page=...mart&Itemid=55

ian
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Old Jan 03, 2012, 03:29 PM
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Thanks Ian, I didn't know that.
I love my Bee wings and my Rebels too, but I also really like a well built Raider.

The RiteWings are also highly regarded.

For some reason i always thought the Sonic was a 60"er.
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Old Jan 03, 2012, 07:41 PM
NY Slope Dog
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My elevator is so hairy now I can't say, but it's back enough to have given the (standard) Bee a fair shot. But it really sucks inverted. It's the same one I've flown for 10 years at the MWSC and it's won a few times so I know it's a good combat plane. It is very light though and it does best when the wind is down. No spar, just Zagi tape.

I don't want this for combat, just for mild aerobatics close to the ridge, as a good wind dummy before throwing something heavy.

Bowman used to have an "Aurora" which is a lot like the Bee, except the ailerons were reversed (wider tips). But the Sonic is a great energy plane when simply covered in cote, no goop or anything special beyond the usual FG tape job.

I thought you'd say the BeEVO was a good plane inverted. That's what the Windrider web site implies (thinner foil).
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Old Jan 04, 2012, 12:39 AM
F3B
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A halfpipe would be good then. Fast and good inverted.
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Old Jan 04, 2012, 09:33 AM
powered by caffine
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Joe
check out the scorpion from off the edge sailplanes [url]www.offtheedge.com.au

fred
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Old Jan 04, 2012, 12:05 PM
NY Slope Dog
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Thanks guys, I'll check em out.
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Old Jan 04, 2012, 12:43 PM
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Quote:
Originally Posted by satinet View Post
A halfpipe would be good then. Fast and good inverted.
Halfpipe is not the plane for mild aerobatics in close. It generally just doesn't build
up that light, and is always going to be a fast cruiser rather than an aerobatic plane.

I'm still mystified as to why Joe says his Bee doesn't like to fly inverted.
I stand by my earlier assessment. The Bee flies *great* inverted. Dawson has
made several vids showing the Bee doing in close aerobatics. I'm still curious where
exactly your CG is. Normally we fly it around 8.5" from the nose, and if you set
it a few mm behind that, it'll fly inverted, hands off. You mention "hairy" elevator..
With the CG close to 8.75", I've had the elevator rates as low as 12%. It's possible
your elevator rates are just too hot for smooth inverted flight.
But 10 years is a long time for any foam wing. Maybe it's time to build a new one.

Not sure why one would automatically associate thinner airfoil (which the Beevo certainly
has) with better inverted performance. The problem with the Beevo, as I said before
is that it slows down with aggressive maneuvering, which is a trait of thinner
airfoils which are less forgiving of high angles of attack. Makes it pretty worthless
as a combat plane, and not that great for aerobatics, for the same reason.
It's fast if flown smoothly in smooth air, but slow and prone to tip stalls in bumpy air
or flown aggressively.

ian
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Old Jan 04, 2012, 09:05 PM
Aerobatics!
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Pretty much any of the modern combat wings will suit you well. Just remember - most of the time it's about the pilot, not the plane.
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Old Jan 04, 2012, 09:28 PM
Where's the wind?
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I'm guessing its a CG thing as well. How much stick do you need to fly inverted Joe? If it's more than a smidge, it's nose heavy. Joe's Bee is very light and squishy and this probably has something to do with energy retention. Oh, and Bee's fly better in Colorado.

I think Joe's got the thumb thing down. Have you ever seen him fly 3D.

Andrew
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Old Jan 05, 2012, 12:46 AM
NY Slope Dog
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My Bee weighs 15.5 oz. My Sonic Weighs 18.5 oz. The Bee CG is 7.75" from the nose. Any further back and it doesn't recover well in turbulence. It's my combat plane and I don't want to keep tweaking it, but it NEVER flew as good as my Sonic does and they're about the same age.

Inverted is hard to say. I always trim with a fair amount of down (so I'm always holding some up for level flight) so inverted is almost always hands off. But I've already trimmed each to be "best" for the conditions I get most. If yours balances someplace else, all I can say is our sweeps may be different and/or ailerons are different shapes giving different planforms.

See the pics: About the same wing sweep on the LE. The TE shows the higher aspect ratio of the Sonic.

By "mild aerobatics" I was mostly saying I dont' want to do a lot of hard pulling. I want to carve smoothly in the highest lift zone so being able to penetrate (inverted or upright) is the prime consideration-- so speed is what I want most, yet in a relatively light wing so when things DO get hairy I can still yank a bit and while I expect to dump most of the energy, it won't snap into the ground.

My hill is only 80 feet tall and it's a sheer cliff, so when I do get wind I also get a lot of horizontal component near the lip. Breaking through that and playing in the shear edges of "bowl" formations is where th fun is.

I can only get about HALF the diameter of an outside loop with my Bee compared to my Sonic. 3 oz doesn't explain that.

I can't prove which foil my Bee has compared to yours, but I believe it was the only one available when I got it. It's a great plane and flys when even the weasels won't stay up, but the penetration and inverted performance lead me to believe it's got a "lifty" airfoil and it's just gotta be that way.

I'm also at sea level. (~400 feet)
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Old Jan 05, 2012, 06:41 AM
F3B
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I thought the best cg was about 8.5"?
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Old Jan 05, 2012, 09:33 AM
NY Slope Dog
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Maybe on Ians. Like I said, the sweep could be different. The light lift performance is VERY GOOD (also an indicator of an aft CG).
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Old Jan 05, 2012, 01:36 PM
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7.75" CG is super nose heavy. The Bee's airfoil hasn't changed (except with the Beevo).
The irony here is, I probably bought my first Bee because I heard
of Joe's positive results with it in combat at MWSC when it first came out.
But the performance tuning of the Bee has evolved since then.

Yes, the original (possible still is) recommended CG from Ming for the Bee was 7.5" and it
will fly there OK, but that CG was meant to work with a radio with minimal or no
rate control on elevator. We immediately started moving the CG back further
and further, while reducing the elevator rates. 8.5" is sort of the sweet spot
for a combat plane, with the elevator rate somewhere between 15-20%.
I like to set mine up so that I can pull full elevator and it'll do a quick loop without
a tip stall. Some people like a bit hotter rates (25%), but they will sometimes flick
it in aggressive combat.
At that CG it will pull *tight* loops, both inside and outside, and cruise inverted with
a little down (which we usually control with the very popular throttle->elevator mix at 5-7%).
It recovers well at that CG. If you move it back closer to 8.75"
and reduce the elevator rates a bit further (12-15% max), it becomes
totally neutral and doesn't care which way is upright. It does not recover
from hits quite as well at that CG, but it is an aerobatic monster.

We've also increased the size of the winglets more and more over the years
and often have at least 2 inches hanging behind the trailing edge of the
elevons. Makes for very fast recoveries.

I know this formula works. Dozens of here in Colorado follow it, and
we've collectively built hundreds of these wings.

BTW, here's a vid of Dawson having some fun with his Bee on a relatively low lift slope.
Freestyle Slope Flying with a Predator Bee, Mormon Lake Overlook, 07-29-09 (3 min 23 sec)

There's a nice inverted loop in there around 1:25, and obviously not much
preference for upright in the rest of the vid. I should do a proper Bee
vid someday.

ian
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Old Jan 05, 2012, 03:21 PM
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I guess I should thank both of you for bringing me to the Bee.
ian, how about your Bee on a cliff face vid? That one's pretty good. I think your father shot it.
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Old Jan 05, 2012, 05:55 PM
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By "mild aerobatics" I was mostly saying I dont' want to do a lot of hard pulling. I want to carve smoothly in the highest lift zone so being able to penetrate (inverted or upright) is the prime consideration-- so speed is what I want most, yet in a relatively light wing so when things DO get hairy I can still yank a bit and while I expect to dump most of the energy, it won't snap into the ground.

sounds like a halfpipe to me in the lightbuild. probably just tape on leading edge and put winglets on to reduce more weight.

just my 2cents and am no were the flier these guys are.
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Old Jan 05, 2012, 05:56 PM
NY Slope Dog
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Ok, I have a couple Bees NIB that I'll get together and try your new recommendations. Thanks for the details.

You got me thinking both Sonics I've have use compression tape hinges, while my Bee always just had top hinged beveled balsa with that weak zagi tape. Seemed to be strong enough but I now wonder if there is any hinge play which could make my transition from upright to inverted so bad. It's literally like throwing the breaks on inverted with the plane as it stands now, so maybe some of the upright trim was getting flexed too much and in the transition it dumped everything? When you've only got 20% elevator, maybe if your hinge wastes half of that it might explain things?

One move I sorta "invented" years ago with my Sonic was what the indoor 3D guys are now calling "the snake." You just do a bank close to knife edge, and throw it back and forth positive and negative G in a serpentine fashion. My Bee could never do that. Wonder if it was the hinges or those long flexy push rods? Both Sonics have music wire on internal plastic guides to minimal exposed control horns.

I also got a lot of great flights from a Birdworks "MOG" which flew super in any lift condition from crazy light to over 40mph and that also sucked inverted. I know for a fact the CG was as far back as possible in each wind extremity, and now I'm wondering if the hinges were to blame for it's bad inverted showing as well....(also tape top hinged with long flexy push rods)

I like compression hinges a lot better so I'll likely do one up proper with internal servos and push rods for smooth speed mods-- although no goop cause I still want lightness.

Maybe part of my problem is I'm still flying some stuff with ancient technology.
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Old Jan 05, 2012, 07:57 PM
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Old Jan 06, 2012, 01:25 AM
setting CG with ceiling fan on
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Quote:
Originally Posted by Wind Junkie View Post
One move I sorta "invented" years ago with my Sonic was what the indoor 3D guys are now calling "the snake." You just do a bank close to knife edge, and throw it back and forth positive and negative G in a serpentine fashion.
My Bee2 (at around 17 oz.) will do this very easily. My combat foes will back me up on this. It's a fun move! CG is dead on 8.5" and my winglets are a couple inches longer than stock and stick out under the wing about 3/4". They also have 3 carbon sticks in the coroflute on each one. Inverted flight is very good as well. It's my best wing for outside loops too. It flies in surprisingly light lift for its weight.

It's good at combat and very close (if not equal) to the speed of the Zagis. It's quite a bit tougher though, built Predator style.
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Old Jan 06, 2012, 01:40 AM
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Quote:
Originally Posted by Wind Junkie View Post
When you've only got 20% elevator, maybe if your hinge wastes half of that it might explain things?
These days we usually bottom hinge the elevons to keep the control horns
shorter for combat, while maintaining higher resolution and theoretically less drag,
but it's not necessary for a good inverted flight. Some of my best Bees were top hinged.
I hinge my elevons with 3M clear packing tape (750 or 850 series) which
sticks to itself at the hingeline much better than almost any other tape
including the Zagi tape (which I don't use for anything any more).
Some people add 3 sets of tension hinges under the clear hinge tape (at both ends
and near the horn). I usually just hinge it normally, and add tension hinges
later in the field as needed.

Quote:
One move I sorta "invented" years ago with my Sonic was what the indoor 3D guys are now calling "the snake." You just do a bank close to knife edge, and throw it back and forth positive and negative G in a serpentine fashion. My Bee could never do that.
I discovered that one circa 2006 with my LED (night) Bee.
When all you can see is the lights as it's pointed away while doing that move,
it looks like a tick tock. My LED Bee (one of my best fliers) certainly doesn't slow
down doing it. In the right wind, I can maintain it almost indefinitely.

Quote:
Wonder if it was the hinges or those long flexy push rods? Both Sonics have music wire on internal plastic guides to minimal exposed control horns.
My LED Bee has long exposed 2-56 pushrods and doesn't have any problems.
We mostly use Golden Rod through the wing these days because it's stiff, but
can still soak up a combat hit without snapping the servo arm or stripping gears.

Quote:
Maybe part of my problem is I'm still flying some stuff with ancient technology.
Could be.

ian
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Old Jan 06, 2012, 08:24 AM
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Several years ago I started using both tension and compression hinges on my JW's and now all my planes get them. Really keeps the hingeline true.
Thought I was one of the only ones using both...then I got an old Boomerang kit where he recommends it in the instructions.
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Old Jan 06, 2012, 01:43 PM
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what's the difference between a compression and tension hinge? I thought it was the same thing.
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Old Jan 24, 2012, 01:44 PM
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Sounds like some good advice here. By the way my elevator literally did get "hairy"-- strands of fiber hanging off from where the bi-directional strapping tape I used for a hinge was starting to decay after the plane spent a week up in a tree -- caused a weird aerodynamic phenomenon where the same servo position would give several different trim results and sometimes it was suddenly hard to get the nose down even w/ full down.... I think all entirely a result of aerodynamic disturbances not the elevon actually being loose...

Quote:
Originally Posted by Daemon View Post
Halfpipe is not the plane for mild aerobatics in close. It generally just doesn't build
up that light, and is always going to be a fast cruiser rather than an aerobatic plane.

I'm still mystified as to why Joe says his Bee doesn't like to fly inverted.
I stand by my earlier assessment. The Bee flies *great* inverted. Dawson has
made several vids showing the Bee doing in close aerobatics. I'm still curious where
exactly your CG is. Normally we fly it around 8.5" from the nose, and if you set
it a few mm behind that, it'll fly inverted, hands off. You mention "hairy" elevator..
With the CG close to 8.75", I've had the elevator rates as low as 12%. It's possible
your elevator rates are just too hot for smooth inverted flight.
But 10 years is a long time for any foam wing. Maybe it's time to build a new one.

Not sure why one would automatically associate thinner airfoil (which the Beevo certainly
has) with better inverted performance. The problem with the Beevo, as I said before
is that it slows down with aggressive maneuvering, which is a trait of thinner
airfoils which are less forgiving of high angles of attack. Makes it pretty worthless
as a combat plane, and not that great for aerobatics, for the same reason.
It's fast if flown smoothly in smooth air, but slow and prone to tip stalls in bumpy air
or flown aggressively.

ian
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Old Jan 24, 2012, 03:13 PM
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Quote:
Originally Posted by satinet View Post
what's the difference between a compression and tension hinge? I thought it was the same thing.
A tension hinge is a pair (or more) of the over/under tape hinges. Compression is the full length tape on top and bottom.
I helped maiden a 28oz(ish) Bee here last week. CG about 8.5"(ish) flew perfectly fine inverted. Outside loops, inverted 1/2 pipes, I think the ele rates were about 40% and could have gone down to 30-25%.
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Old Jan 24, 2012, 06:47 PM
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There's a couple different styles of compression hinge too.
In one, you're mating a square edge (sub trailing edge) to a beveled edge (front
of control surface). Typically stick the full length of tape down to the wing with
half width hanging over the back into open space (don't rub it down so much that it curls).
Then hold the control surface at full deflection angle (beveled face against square sub TE
face) and slide it up until the sharp edge at the top of the bevel makes contact along the whole
length of the tape, sometimes leaving a *tiny* gap between surface and sub TE. Stick the tape down
good, then flop the whole surface over up onto the wing, and apply 2nd strip of tape flat against face of sub TE
and the bevel, ensuring that it sticks to that tiny strip of tape showing through at the
hingeline, and then smooth the edges down onto the surface and wing. In the end you
want 1/16th of an inch or less of tape stuck to itself along the hingeline. Many of us
know this as the "Zagi style hinge" as they were one of the first to specifically
document it that way.

The 2nd style compression hinge, we've always known as the "JW style hinge"
since Bowman popularized it in the JW instructions
It's used when hinging a square sub TE edge to a round control surface edge (a lot
of aileron/elevon stock is sold with a round leading edge). Again, start by
sticking full length strip of tape down to the wing, half width on/half off. Then
turn over and lay flat on its back (sticky side up) and place three little 1/8th inch
spacers (cut em out of balsa) onto the sticky tape, against the face of the sub TE.
Then very carefully place the control surface flat down onto the sticky tape
while simultaneously pressing it against the spacers. Ultimately want
a 1/8th inch gap between surface and sub TE for its entire length.
Then remove spacers, and stick a piece of tape down half onto the wing,
half onto the surface with the 1/8th inch gap in the middle. Then run finger tips
along the gap both top and bottom while pushing the surface toward
the wing which causes the two pieces of tape to buckle toward each other into
the gap until they eventually touch. Use a pointy stick to rub the hinge line
so the tape sticks to itself. Again, looking for about 1/16th inch or less stuck to itself.
If the gap is too small, the tape won't stick to itself at the hingeline, or
will pull part as it tries to deflect. Too big a gap and you just get a floppy hinge.

For both you need a tape that actually will stay stuck to itself under tension. Most
clear tapes don't do that. Stick them face to face, and then pull gently and
they'll slowly pull apart. 3M 375 and 3850 are the only strong lightweight clear tapes I know of
that when you stick it to itself face to face, and then pull apart, it will hold firm
up to a certain tension, and then only separate grudgingly, often only after
pulling adhesive from the backing. 3850 can usually be sourced locally but
isn't as strong as 375.

Cool thing about tension hinges though, is that they can hinge any shape to any other
shape and can be added prior to installing Zagi style full length hinges to ensure
proper alignment, or added later to any other type of hinge system to force
them into alignment.

ian
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Old Jan 24, 2012, 06:52 PM
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BTW, I seem to recall the original Bee instructions used the fiber tape for hinging
and only had the tape on the top surface. That's a recipe for a floppy hinge that'll
peel off the wing or surface. A lot of people have done hinges this way on a lot
of planes.

ian
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Old Jan 25, 2012, 01:41 AM
Objects in mirror are losing
1000MPH's Avatar
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Quote:
Originally Posted by Daemon View Post
There's a couple different styles of compression hinge too.
In one, you're mating a square edge (sub trailing edge) to a beveled edge (front
of control surface). Typically stick the full length of tape down to the wing with
half width hanging over the back into open space (don't rub it down so much that it curls).
Then hold the control surface at full deflection angle (beveled face against square sub TE
face) and slide it up until the sharp edge at the top of the bevel makes contact along the whole
length of the tape, sometimes leaving a *tiny* gap between surface and sub TE. Stick the tape down
good, then flop the whole surface over up onto the wing, and apply 2nd strip of tape flat against face of sub TE
and the bevel, ensuring that it sticks to that tiny strip of tape showing through at the
hingeline, and then smooth the edges down onto the surface and wing. In the end you
want 1/16th of an inch or less of tape stuck to itself along the hingeline. Many of us
know this as the "Zagi style hinge" as they were one of the first to specifically
document it that way.

The 2nd style compression hinge, we've always known as the "JW style hinge"
since Bowman popularized it in the JW instructions
It's used when hinging a square sub TE edge to a round control surface edge (a lot
of aileron/elevon stock is sold with a round leading edge). Again, start by
sticking full length strip of tape down to the wing, half width on/half off. Then
turn over and lay flat on its back (sticky side up) and place three little 1/8th inch
spacers (cut em out of balsa) onto the sticky tape, against the face of the sub TE.
Then very carefully place the control surface flat down onto the sticky tape
while simultaneously pressing it against the spacers. Ultimately want
a 1/8th inch gap between surface and sub TE for its entire length.
Then remove spacers, and stick a piece of tape down half onto the wing,
half onto the surface with the 1/8th inch gap in the middle. Then run finger tips
along the gap both top and bottom while pushing the surface toward
the wing which causes the two pieces of tape to buckle toward each other into
the gap until they eventually touch. Use a pointy stick to rub the hinge line
so the tape sticks to itself. Again, looking for about 1/16th inch or less stuck to itself.
If the gap is too small, the tape won't stick to itself at the hingeline, or
will pull part as it tries to deflect. Too big a gap and you just get a floppy hinge.

For both you need a tape that actually will stay stuck to itself under tension. Most
clear tapes don't do that. Stick them face to face, and then pull gently and
they'll slowly pull apart. 3M 375 and 3850 are the only strong lightweight clear tapes I know of
that when you stick it to itself face to face, and then pull apart, it will hold firm
up to a certain tension, and then only separate grudgingly, often only after
pulling adhesive from the backing. 3850 can usually be sourced locally but
isn't as strong as 375.

Cool thing about tension hinges though, is that they can hinge any shape to any other
shape and can be added prior to installing Zagi style full length hinges to ensure
proper alignment, or added later to any other type of hinge system to force
them into alignment.

ian
Really valuable info.
I suggest everyone bookmark this post.
IMO, a good hinge is what separates an average foamie from a great one.
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