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e-Ikarus Piccolo-Eco 8/16 > ECO 8 Frame Re-Design - Build
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Hi,

I am in the middle of building my latest project involving my ECO 8 and wanted some feedback on what I am doing, basically I have redesigned the entire layout of the frames to achieve a few things that I wanted from the heli -

The layout changes the position of the motor and also the tail drive -



The idea is to move the CG further forward so that I can use a wider range of lipo batteries as I was finding it difficult to get a good balance, the heli was designed of course for NiCd etc. I have done this by building a gearbox to lay the motor flat, I use mitre gears to do this -



This also gives me the option to use a wider range of motors as there are now no clearance issues. I machined the gearbox on my manual mill, very pleased with the way it runs.

I decided to run the tailbelt directly from the mainshaft so got hold of a range of pulley's from 80 to 84 tooth which will give me the correct gearing range for experimentation, the gear sits just above the maingear -



Removing the intermediate gears will offset any drag caused by the mitre gear setup, it certainly runs very freely.

There are two sets of frames one at the standard width of 25mm acting as the main chassis, the other at a wider width to hold the battery -



The battery sits on a support tray and is held in place with cinch straps, it will take batteries up to 28mm deep which would cover pretty much all suitable batteries.

The advantages of all this is -

1. Better CG
2. Shorter mainshaft, less possibility of bending
3. Better housing for batteries (I hate the way they are held at the moment)
4. The weighty items are positioned much closer together vertically and the motor is directly along the line of the tailboom which will give faster roll rates.
5. The tailboom is 18mm lower increasing the distance from the mainrotors to reduce tail strikes.
6. Better provision for Gyro and electronics
7. Direct taildrive is more efficient
8. Stronger construction, the main chassis is much smaller and very rigid.

The only disadvantage I can see is the extra weight but I believe the motor/battery setup I have is more than capable of giving good performance.

Build -

I have the main frames built using 1.5mm carbon sheet -



The frames hold the motor at the front as can be seen, I havent trimmed down the mainshaft yet until I am happy with its position.

The tailbelt is guided with two jockey pulley's from a Hirobo -



I used a tailbelt from an ECO 16 which amazingly fits great and the system works really well -



I have bench tested this setup with the motor running at high RPM and it is very smooth at this point -



Next stage is to build the sub frames and landing skids.

I will post more details of the build as it progresses, it will be interesting to see how it flies when its done!

Any opinions or ideas would be great

Ken
08-19-2006 Over year old.
HOMEPAGE  
 
 
i8urls6
Senior Heliman
Location: Troutman, NC

Very thoughtful design. Keep us posted.
08-19-2006 Over year old.
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Finished cutting out all the carbon components, gives a better indication of the design with the lower frames attached -



The lower frames are in 1.5mm and are attached with M2 threaded spacers and offset from the main frame with standoffs (havent finished making these yet) -



The Battery and ESC tray's are in 1mm Carbon.

Next task is to mount the servo's so I can get the length of the mainshaft correct
08-20-2006 Over year old.
HOMEPAGE  
 
 
Kosmic
Heliman
Location: Canada

as usual really impressive. Continue your good work !
08-24-2006 Over year old.
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Thanks Kosmic, what I am doing is probably nuts but boy am I having fun

Fitted the servo's in place, everything checks out ok -



Assembled the head and fitted to make sure the shaft is in the right position, also made and fitted the remaining spacers and standoffs -



next up is the landing skids which I hope to get completed over the weekend.

Question for everybody -

The way I have the taildrive planned differs from the standard ECO in respect that drive is maintained to the tail at all times even with an autorotation hub fitted. I havent had much experience of Auto's but would you want drive maintained to the tail during motor loss or not.

The standard ECO with an autorotation hub would cut power to the tail at the same time as motor loss, no doubt a good Gyro would compensate with extra tail pitch to some extent. With this system as the main blades autorotate the tail blades would remain driven. However this would be big trouble if the tail gyro or servo went awol so which is best? The reason I ask is that it occurs to me that the tail drive pulley could be bolted to the main gear to save space but this would give the heli different characteristics.

Any opinions would be appreciated
08-26-2006 Over year old.
HOMEPAGE  
 
 
Optech
Key Veteran
Location: Vista/Oceanside, CA.

Maintaining drive to the tail during autos is pretty much standard now as they are neccessary for aerobatic autos. Especially if you use 3D fins. In the old days, without driven tails, you always tried to auto into the wind as you lost directional control. But, we had solid fins that acted as rudders to at least keep the tail behind the heli. The newer 3D fins prevent this somewhat.

On the other hand, smaller helis like T-Rexes and most electrics use very light blades that don't auto well anyway. Not enough mass. What momentum/energy they do generate is migigated by having to drive the tail further compounding the problem. It takes great skill to auto a T-Rex and you have to be perfect every time as there is no momentum/energy in the blades to make up for mistakes/miscalculations. Again, the flip side is that it also takes great skill to auto a non-driven tail although you may have a bit more blade energy to work with.

So what's the answer, In general I would prefer a driven tail. However, I could do without one on my T-Rex as I don't generally auto it anyway. The Eco has larger, heavier blades so it would probably benefit to have a driven tail.

Mike

Viva La Airtronics!
08-27-2006 Over year old.
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Thanks Optech that makes perfect sense, so it sounds like I have made the right choice in keeping the tail rotor driven, thats not actually the case with the standard ECO once the Auto-Rotation hub does its job.

Completed the landing skids which are in two parts, first are some struts which I made out of 12mm Delrin -



The skids themselves are in 3mm thick Delrin, the struts have a keyway into which these slot then I used a heat gun to bend the skids finally bolting them in place -



I designed the skids to mirror the shape of the lower frames. The whole assembly then bolts in place like the standard ECO, the struts also support the battery tray -



Almost there now should be flying by next weekend
08-28-2006 Over year old.
HOMEPAGE  
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Nearly there now, got held up with parts waiting to be delivered.

Really pleased with the tailbox from http://www.rc-city.de -



Its a nice unit and sleeves over the carbon boom so no more splitting hopefully. Made the tail control rod out of an alloy arrow shaft, light and strong and wont split like carbon can.



The mainshaft has been cut down in length by 22mm, I machined a slot in a collar to accept the pin as this rides against a bearing mount usually used at the top of the shaft. The shaft is hardened so all tools had to be carbide tipped.



All the mechanics are made now just a matter of wiring up and trimming out. I made a boom mount for the tail servo and extended it to mount the base loaded aerial so its away from all other components.

Should be flying tomorrow
09-16-2006 Over year old.
HOMEPAGE  
 
 
jaylad
Heliman
Location: wolves ,england

looks fantastic,hope she flys as good as she looks
09-17-2006 Over year old.
 
 
mjdee14
Senior Heliman
Location: Nashville , TN

Eco 8

"WOW"...quite an accomplishment.....post vids of the flight if possible.

Good luck....nothing better than seeing something fly you "made" with your own two hands....

Again..."Great Job"

Mike

Mike... Blade CP, HBCP2, Revo w/belt drive, Zoom 400, Eco 8, Hurricane 550, DX7 2.4
09-17-2006 Over year old.
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

ECO 8 Frame Re-Design - First Flight

Thanks guys, too right it flies -



I am so chuffed, did some hovering before the weather closed in, only managed to trim the tail which is rock steady, all trims left as is it is hovering so stable and really smooth, the CG is spot on so no more having to dial in some forward cyclic. I was shaking like a leaf when I first spooled it up, sat there letting it tick over at high rpm before I plucked up enough courage to push the throttle forward. It is definately smoother on the throttle than stock I am sure there is less drag without the intermediate gear for the tail.

I am using an 18 tooth pinion, I havent got a tacho but the headspead is really high and response is fantastic I can tell that its going to fly really well.

Gearing is noisy compared to stock, it sounds like a turbine I actually quite like it, it will close in once the canopy is on



Next stage is the canopy, the stock canopy fits but I intend to model something special in clay on the chassis, it will take me a while but I will get some more flights in first.

I will post picks of the canopy build as I go. You are right mjdee14 there is nothing like seeing something you have designed and made yourself take to the air for the first time
09-17-2006 Over year old.
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jaylad
Heliman
Location: wolves ,england

how cool is thst,very nice well done,keep us posted on canopy and flights
09-18-2006 Over year old.
 
 
thewade
Heliman
Location: Atlanta. GA

The million dollar question..........can you build another?
09-19-2006 Over year old.
 
 
Rob_T
Elite Veteran
Location: Tualatin, OR - USA

My hat's off to you dude

Heli_madken, that is absolutely awesome. My hat's off to you dude!

I think you've done a better job of re-engineering the Eco than Ikarus have done with their Royale!


Rob
Eco8, Piccolo Fun, Shogun, HB Elite CP, Trex 450XL CDE, Swift
09-19-2006 Over year old.
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Thanks Rob, must admit I am pretty pleased with it

thewade, the biggest problem about making another is machining this little monster -



I only have a manual mill and it took hours of work from a solid billet, if I was going to make them I would have to source someone with CNC capability.

I am not sure how much take up there would be on the ECO to start manufacturing this kit, that said what I had in mind when I did the design work was the basic idea of a generic kit to take different heli's to electric power, eg take a Raptor 30/50 head and transplant it, only thing that needs to change is the distance between the frames to accomodate the larger bearing blocks.

The other problem is the amount of carbon fibre which would make the kit expensive, it is worth thinking about though

I will post pics of the clay canopy plug for opinions as I go along
09-19-2006 Over year old.
HOMEPAGE  
 
 
djtilko
Senior Heliman
Location: United Kingdom Leeds

Your an inspiration to all of us Ken! what a supurb looking heli! I should be ashamed of my self for buying so many parts that I could have made with just a micro nano of the thought youve put into this baby

I have been given some rod the same size as the eco 8 main shaft and would like to cut it up into main shafts and drill it would that be possible without lathe equipment? I do have a pillar drill.

If your heli could be marketed there would be a good demand for it I am sure! this size heli is a little short in supply now, the Swift is good but its bigger and theres only the trex inbetween the market needs this size heli imho!

Dave
09-20-2006 Over year old.
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Thanks djtilko

It depends on whether the rod is hardened steel or not, I personnally wouldnt use mild steel I think 6mm is marginal for the ECO shaft anyway. If its hardened steel it is a little more difficult but either can be done without a lathe and certainly with a pillar drill.

With hardened steel, If you have a dremel use a HD cut off wheel to trim the rod to size. Lay an existing shaft on top of the blank and tape together tightly (any strong tape will do) with the existing shafts pin bores vertically upward away from the blank, use a 2mm drill bit in the hole to get the verticality as accurate as you can.

Now clamp both together in a drill press and use a 2mm carbide tipped drill working slowly through the blank with the aid of cutting oil.

The idea of using the existing shaft as a guide is to stop the drill bit from slipping as it starts its cut and also you end up with a totally accurate shaft without measuring
09-20-2006 Over year old.
HOMEPAGE  
 
 
djtilko
Senior Heliman
Location: United Kingdom Leeds

Ken brilliant advise thanks

Djt
09-22-2006 Over year old.
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Spent some time designing the canopy and making the clay model -



Let me know if you think I am on the right track with the shape.

Covered the heli in cling-film first to protect everything (I know some of you will get excited by this calm down ) Then carved the model in modelling clay taking time to get both sides symetrical.

This stage is only to get the rough outline and make sure of the correct clearances, then the fun part covering in plaster bandage -



When set I will split it in half then create a plug using car body filler by casting two halves from the plaster cast, I can then refine the shape ready to cast the mould in glass fibre.
09-24-2006 Over year old.
HOMEPAGE  
 
 
heli_madken
Senior Heliman
Location: Liverpool, England

Got up to primer stage with the canopy -



I have designed it so I can fit the whole canopy or just the front -



The rear section covers the electronics -



Having made the clay model and covered it with plaster bandage I was able to split it in half and remove the mould from the heli -



I then filled both halves with a thin layer of car body filler, removed, joined together then spent some time refining the shape and trimming until I had a good plug of the canopy -



I split this into two sections for the front and rear halves of the canopy then in turn cut in half to create the moulds -



Then it was just a case of casting out using glass fibre tissue to make the canopy as light as possible -



Once done it was joining, fitting/trimming, filling lots of rubbing down then primer.

Next stage is paint and graphics
10-08-2006 Over year old.
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e-Ikarus Piccolo-Eco 8/16 > ECO 8 Frame Re-Design - Build
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