Dreamflight Libelle

[arun 0]

Thinking of getting one - anyone got one? There's plenty of info on the Internet but always good to hear it from someone known! Particularly interested in servo choice as size is critical, but the Hitec HS35 around which it was designed is impossible to come by...

[Bravedan 106]

Yes, have one. Just prepping the light wind glider fleet inc it now as off to Wrotham slope today.

 

 

 

Bought from T9hobbysport with the package of battery and some Gening digitals. On my Taranis using a RC Settings website .eepe setup file (modded) which gives four spoken flight modes, spoken timer, triple rates, flapperons/spoilerons on throttle stick, etc, etc.

 

I have flown it at Fickleshole when nobody else flying there to be able to stand in the middle of the patch and spin round like a whirling dervish. (OOOPS, I didn't get it noise tested first!!!! )

 

Opinion:-

 

Its very well moulded and the fits are superb.

 

The wing and tailplane fixing is good, the tail fin fixing design is crap and vulnerable on landing (you soon learn to catch it) and handling in store and car.

 

The tail surface rod clevis ends are poor, the screws are too long as is and they WILL jam, and the screws loosen/strip to release the rods so the ends need gluing, and you might as well use that from the start, except you get no second chance on the lengths.

 

Space is tight....not as bad as some, but still an issue (they all are!). I have the smallest 4Ch FRSky Tx which needs a Y lead, but no room for commercial, so made my own.

 

 

At this point I should say I have numerous small gliders inc two Mk 1 Dreamflight Alulas (VERY different to the "current" moulded one)and some own designs.

 

The Hitec servos are by wide repute rubbish, so not being obtainable is a GOOD thing.

 

The Genings are cheap.......... and fairly nasty. AVOID if possible.............. but if severely limited on cost, they are probably the only way to go.................

 

I had one arrive faulty, as have others, and on the ones that do work, the resolution is quite poor..........trust me on this one, like the Alula Mk1, get high res servos in there regardless of cost, they WILL transform the beast. No good if the servo steps either side of what you need at any one time, is it!!! I still have Genings in apart from rudder as they will take a while to get out carefully being glued in.

 

The best combo of price and res quality is IMO the Dymond 4.7, sold in this country as the over priced RipOffMax SD100.

 

Now to the flying, obviously as an old git with dodgy thinned disc spine, my height discus launching is not going to be up there with the best. However, my experience is that its not that competent a flat field no wind DLG anyway (though very good for its price point) but more a light wind assisted launch sloper (which others say, too). Catch a Slermal on a little bump and its great fun, but then the Mk1 Alula excelled there, and IMO because of its MUCH greater ease of transportation and strength, still does.

 

 

Since you won't get one (or prob a Mk2 at the Moment, not that it was as good), the Libelle IS a good choice if you don't have money to burn and don't know if you'll like DLG type flying.

 

I'd say you'll like it, you don't have age limiting your throw ability! See you at Colley or Denbie Hills when done ???

[arun 0]

Dave, thanks for the candid advice as always! Hope you had a good day of gliding...

 

The best combo of price and res quality is IMO the Dymond 4.7, sold in this country as the over priced RipOffMax SD100.

 

I was looking at the SD100s before I wrote the original post as heard too many bad things about Genings. Also, I would like to buy some servos that could possibly be used in a more advanced DLG in the future should I so wish. Do you know where the Dymond 4.7 servos can be purchased from for a more palatable price - my searches of the usual far-East vendors have not been particularly successful... or do I just have to suck up Ripmax's price?

 

See you at Colley or Denbie Hills when done ???

 

Well, one step at a time - but I'd certainly like to learn to slope soar at some point!

[Bravedan 106]

" I still have Genings in apart from rudder as they will take a while to get out carefully being glued in."

 

Well, thats a bit easier tonight, as the elevator servo failed today and it went in............

 

Repairable, only the multi split underside plastic pod is broken, the rest is OK, but that is really awkward, and they want £40 for a replacement Fus so they can go for a walk on that one.

 

On the bench that servo cycles over one half of the range 50% of the time, the rest 75%.......so change "avoid if poss" Genings to avoid at ALL COSTS!!!!

[Bravedan 106]

I'd certainly like to learn to slope soar at some point!

 

 

Then get a Flying Wings Slipstream...............

 

http://www.flyingwings.co.uk/index.php?route=product/product&path=66_100&product_id=283

 

From four years ago.........(and still going strong!)

 

[arun 0]

I just ordered my Libelle from Hyperflight. Gone for SD100s all round with the wing sticker set to stiffen things up. Since the SD100s run at HV, I've also gone for a 2s LiPo to power the setup. I hesitated at the cost of the servos, but your post has just made me (even) happier as I hate cutting servos out of foam airframes - esp. if the servo fails and wrecks the airframe in flight!

[Bravedan 106]

Just found that I do have enough SD100's to change all my Genings away. They are slightly bigger in all the right ways so cutting the old ones out won't leave holes.

 

I'm uncertain regards the value of the sticker set in stiffening in any useful way, I don't have it, and from experience (and online onboard camera videos) the biggest flex is the fus stick flexing the whole tail. It would maybe reduce the dings to LE...except I don't have any despite a few knocks, and scrub landings, so is that really a problem?.

 

As they want £40 for a new Fus I'm repairing mine, and in case you are wondering, use the transparent gel type ABS solvent adhesive on the plastic.

 

Some points.........

 

1. The wing fixing in the Fus is not well enough fitted, and don't cut even slits anywhere remotely close to it to get anything in like aerials, etc. Put some metal screws in the two wing fixings with thick oil or grease, then glue the area well.the screws will withdraw leaving a stronger unit. CHECK the sockets are in line with the Fus before fixing, mine were not from new, and certainly were not after the bump yesterday!

 

2. I'm using the max throws I can get, and the rudder is still not effective enough really.

 

3. Do not rely on the canopy to hold the battery in, use a micro velcro strap.

[Martin 0]

Do you know where the Dymond 4.7 servos can be purchased from for a more palatable price - my searches of the usual far-East vendors have not been particularly successful... or do I just have to suck up Ripmax's price?

 

This thread has a discussion of various other names that they go by...

http://www.rcgroups.com/forums/showthread.php?t=778177

 

Martin

[arun 0]

Thanks, in the end I just went for the SD100s - at least if bought in UK I can return if faulty. Phoenix Model Products are selling them for £15/ea which is a good price.

[Bravedan 106]

Be ready, they have shorter leads, and so the extensions to the Rx need to be 200mm ish, not 100mm, and the recess for the plug needs to be other than where they have pre-moulded the recess.

 

Mine is back together.

[arun 0]

Be ready, they have shorter leads, and so the extensions to the Rx need to be 200mm ish, not 100mm, and the recess for the plug needs to be other than where they have pre-moulded the recess.

 

Mine is back together.

 

Good to know, thanks Dave. I ordered 10cm and 20cm extensions with mine as wasn't sure what was needed. At 69p per extension I felt I could stretch to it after the cost of the SD100s

[Bravedan 106]

There simply isn't room for Keeps across the extensions so I have clear taped flat over the whole cable run and the servos area to wind cheat it all. The recesses I have cut are tight enough to hold the joint together.

 

The SD100s fit quite well consider the plane was not made around them. their fixing bracketS are closer to the top but thinner so a simple knife cut on each position allows them to sit in flush and they are held in by two small drops of medium CA on the brackets and the tape.

 

One design feature I don't like at all is that the servos for rudder and elevator are positioned such that their rods and arms are very close to Rx and wiring, esp from the wings. I have used a thin plasticard "partition" to keep away from any possibility that the tiny ultralight wiring might move into the rod run and either get chafed, jammed or shear.

 

Having built a Mk1 Alula years ago to only 89g, now over time, repairs and repaint touch in, still only just "up" to 100g flight ready, the Libelle is a very different beast, well over that weight no matter how anal you are in building, considerably more stable (so less fun!, maybe its not my type of plane, not hooligan enough!) Compared to other DLGs though, its good value for money, and will teach technique.

 

Do try it on a slope, its more wind worthy than it looks.

 

One thing though.....experiment with CG, as small changes make a huge difference to glide performance.

[arun 0]

I've started putting my Libelle together, all very nice quality and goes together very precisely. Only mod I've made so far is to put some 4mm ply wooden mounting rails in the pod for the servos - I'm not a fan of applying cyano to £18/ea servos I might want to reuse!

 

Dave - do you mind posting me a photo of the inside of your Libelle's pod? I'm using a FrSky TFR4B Rx and things are looking very tight

[Bravedan 106]

Hi Arun,

 

4mm???........... The grammes............... .........and screws? more grammes!!

 

I'm not where the Libelle is currently.

 

There is little flexibility in positioning, but then its a DLG weighing a few grammes, not a porky Wot 4!!

 

Working back, I have a little custom shaped lead cut in under the battery to get CG, the battery leads point forwards then loop back down the battery on the receiver side, with a micro velcro loop to hold it all in place (do NOT trust the canopy!!)

 

The battery lead connects to a "Y" lead I made to fit in the gap between receiver and battery bays. I do not like connecting a battery to a receiver direct.

 

I usually wrap the servos in EPP planes with reinforced tape, cut to be single layer fit over all the body, then glue, often with thin hot glue, but on the libelle I used CA.

 

The receiver is fitted in near vertical on one side (with foam removed to lower it) with the aerials forwards, turning back, so the connectors are at the rear near the aileron leads.

 

I have a 1mm plasticard partition keeping all leads away from the control rods and servo arms.

 

As DLGs and micro gliders go, there is acres of space

 

(I had the same shock and learning curve seven years ago with my first Alula, so I'm semi-joking around now, OK, but low weight is EVERYTHING!!

[arun 0]

4mm???........... The grammes............... .........and screws? more grammes!!

 

I was a bit worried about weight, but according to my micro-scales the 4mm lite-ply rails weigh 0.42g and the 4 screws weigh 0.17g each. So weight added approx 1g - given a fair amount of lead needs to go at the nose, and my rails/screws are well ahead of the CG I wouldn't expect this to be a massive problem. It would be easy to add more weight that this with over enthusiastic hot glue application Time will tell when I come to fly it...

[Bravedan 106]

But then as you well know, I'm not overly enthusiastic about anything..........

 

Seriously (see, I can be... ), weight is not THAT much an issue........but get as little as poss as far forward as poss, and worse, allowing the servo leads to get anywhere near the control rods and servo arms IS, esp when you are going to be swinging it around like a loony......

 

My ultra thin but quite stiff partition is not fixed in, but wedges into cut slits at the ends, running between the in pod half pipe carbon tube and the receiver bay to battery bay. Its cut up slightly and the sharp edge blunted with tape to allow the servo leads from rudder and elevator to pass under it and under the Rx in a direct line to the rear facing Rx connections without chafing (as the leads are only just long enough).

 

While on the subject of rotating the thing, be aware that the grooves under the tailplane will work wider as there is only one screw and launch forces and the occasional knock will ease it wider and wider. Ny approach was to stiffen the slots with ultra thin CA while it was off the plane, but you'll find other "solutions" out there. The rudder to boom fixing looks naff, and so to an extent it is, as it is very vulnerable to hangar incidents and even catching the ground and being taken off if you ground land rather than catch, but IMO on balance its better that it comes away otherwise undamaged in a decent knock.

 

While talking tail (steady!), make sure the end clevises are onto roughened carbon rod to grip, and remove any excess screw length as it will jam on the carbon boom, esp when the tailpane starts to move. Now I'm happy with settings I have glued mine as they don't grip that well with a single tiny screw, and it seems its easy to strip the screws from reports.

 

Now to software setup........ As I was always going to use my new Taranis Tx, I picked up a "Libelle" .eepe file and adapted that a bit. It provides:-

 

Fully proportional and fine resolution Flaperon and Spoileron on throttle stick and switch (spoken).

 

One way switch, Launch Mode (spoken, slight rudder offset to counter the swing, and minimal up camber to assist the climb.

 

Three way switch, Speed, Cruise and Float Modes (spoken) affecting wing camber, Speed for example being slightly negative.

 

 

I left hand throw to be able to hold Tx and operate the aileron and elevator while in the climb (NO neck strap or tray). Left hand off the planes launch peg and straight to switch off launch mode into (initially) cruise mode. And it has the usual expo/rates and a few more in flight tweaks I'm not sure are required yet and some gimmicks like timer from launch mode off.

 

These four flight modes, once tuned and head set firmly round using them under pressure (I practised with the Tx at home till it was second nature), are really valuable, not just nice to have's.

[Bravedan 106]

Short Video from yesterday, hardly ideal conditions, a very blustery wind, and lots of sink holes in it. Also my last editing of the Taranis file ended up reversing a few features which still work, but now have switches reversed.............and no time to reset............only SLIGHTLY confusing when its telling you you have flaps and speed mode, when its spoilers and float mode

 

[arun 0]

Flew my Libelle today for the first time at Chobham & District MFC and loved it! Had between 40-50 "flights" with it during which I made some improvements to the launch technique thanks to helpful critique from Martin who was flying at the Chobham site as a guest.

 

Had a couple of fights where the model picked up some nice lift which is very satisfying. I was expecting to enjoy gliding, but I think I might be hooked Made use of four flight conditions; launch - cruise - thermal and land which have varying degrees of reflex/flaps and elevator compensation.

 

All in, good fun. Airframe needed a dab of cyano on the vertical stab where the epoxy I initially used released. Balance is at 5mm behind spar which seems fine to me for now. Highly recommend you guys get DLG-ing!

[Bravedan 106]

Great!

 

The Vertical Stab fixing is one of its worst features.

 

After trying epoxy, thin hot glue, and then CA. I have settled on using the same technique as my Alula Mk1, to allow it to rotate under resistance if hit. To do this I rebuilt (as it was worn) the rectangular "pin" which goes into the boom slot, and located two small cable ties through the reinforced vert stab round the boom front and rear. It will rotate but needs force beyond flying forces.

 

So, when are you taking up slope soaring then? Get a FlyingWings Slipstream..fast, tough and cheap!! (Do not get a Zagi or Si or similar, they are an outdated designs that are slow and poor in iffy lift conditions).

 

You have Box, Colley and other usable slopes in easy reach of you! (Take the Libelle to any of these when the wind is less than 7mph and near square on.)