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Skyartec Skyfun Thread - Printable Version

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RE: Skyartec Skyfun Thread - samste - 24-08-2010

(24-08-2010, 03:29 PM)gbanger Wrote:  Steve
Can you tell me what timing you are running on your Scorpion 2221-8 motor?
Thanks

I'm using mid range timing though you could use high timing though current may increase slightly.

RE: Skyartec Skyfun Thread - gbanger - 27-08-2010

Finally finished the beastie.... Sweeeeeeett!
   

RE: Skyartec Skyfun Thread - wobbly - 05-09-2010

Mornin' fellasSmile I have tried to glue my Skyfun together with some zap foamsafe CA to no avail. The lhs wasn't much help saying that the newer "greasy" surface foams don't like this CA even though they sold it to me....Confused Which glue have you blokes used succesfully? Thanks - JeffSmile

RE: Skyartec Skyfun Thread - robair - 05-09-2010

Gday Wobbly

Personally speaking I would 30 min epoxy the bugger.
Then, use what you have left on the skyfun.

Cheers
Rob B

RE: Skyartec Skyfun Thread - gbanger - 05-09-2010

Hi Wobbly
I used 15 minute Hobby King Med cure epoxy to build my Skyfun and it is as strong as a battleship.
The CA glues are OK but dont have any real tortional strength.
So even if it did glue together OK It would start to fall apart after a few flights. You cant beat epoxy for building. Its pretty bullet proof.
Gazz

RE: Skyartec Skyfun Thread - paulj - 05-09-2010

If you can't wait for a hobby King order to arrive go to Big W or Woolies
and buy Arildite epoxy comes in a 2 vial syringe pack.
I've used the 5 min version heaps of times and never had a problem. You can also
get the 30 min version which will give you that little bit more working time.

RE: Skyartec Skyfun Thread - ~KevJ~ - 05-09-2010

Hey Jeff nice of you to visit over here these guys are spot on with the epoxy that's what we are using to hold em together at 200+ kph so you will have no problems with that..

Hey also thanks for the baja advice on the plaig forum the other day , old mates 5b is back up and running and I'm sticking to my planes for airborne rc from now on..

RE: Skyartec Skyfun Thread - wobbly - 06-09-2010

Hey kev, thanks for the tips fellas. Epoxy will do me then. CheersSmile

RE: Skyartec Skyfun Thread - wobbly - 02-10-2010

Mornin' fellas, "tried" to fly the skyfun last weekend witht he standard motor/esc and couldn't keep it going. It kept wanting to stall everytime I pulled back on the stick.....Might have been the 2200 mah 3S was a bit too heavy methinks. I am fitting this motor atm http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=7993 and I am going to try my lhs for a prop this morning. I know they have the bluebird brand props in the size I need as I got one for the electrafun when I did a b/less conversion to it (thanks for the info that time too Kev) The e/fun had the same prob with the standard donk I found, it was slow and would only climb very gently, too much elevator input and it would stall, but with a b/less on 2S it was more enjoyable. By no means a rocketship but a bit more usable power to help the takeoff easier for a beginner. Any recommendations for aprop? 6X4 perhaps? Thanks fellas Smile

RE: Skyartec Skyfun Thread - kizza42 - 02-10-2010

Where did you place the battery? If you had it too far forward that would make it hard to fly with low power. We've flown with much much heavier batteries.

RE: Skyartec Skyfun Thread - wobbly - 02-10-2010

I had it balanced reasonably well by the finger holes. Confused

RE: Skyartec Skyfun Thread - popeyepete - 23-02-2011

Picking up one of the Skyfun kits in my order of stuff from HK, couldn't just order EC3 plugs, spinner, spare motor shafts and NO PLANE!!

My mix of spares should be able to kit out the jet, just wondering weather this motor would suit, Turnigy Typhoon 2218H 3450kv;
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9257

I have a 50amp ESC and will be probably running a 3S 2200mah 40C. Don't know what prop yet.....

too big???

RE: Skyartec Skyfun Thread - kizza42 - 23-02-2011

Would be a good start, Aim for APC 5x5 and go from there.

I ran this:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9383

4 Cell, 7x5 prop, 1000 or so watts. You must replace the elevons to handle that kinda speed though

RE: Skyartec Skyfun Thread - samste - 03-05-2011

Hi Jason (Secant0give)

Quote:What motor are you running in yours? I've ordered the 2836 -2300KV
http://www.hobbyking.com/hobbyking/store...oduct=7993

I was also looking at this one, Same motor body just wired for 3200KV
http://www.hobbyking.com/hobbyking/store...oduct=8138

I was considering using only filament tape to toughen the
wings mainly because of weight. I could put in a carbon spar but we used to fly slope soarer's with just tape on foam and they went pretty fast and pulled high G's. they never failed in the air, Sometimes when conditions permitted they were heavily balested as well.

Have you ever heard of a funjet failing in the air with out a carbon spar or clapping wings ?? I know Kizza's striker suffered flutter and failed a linkage.

I'll have a look at the forums tho' looking the airframe I'd think the main mode of failier was impact with the ground.

Have you got any interesting funjet links??

This is the Funjet Thread that Kev Started Started as i originally imported a whole lot of Funjets from Overseas before they became available on Hobbyking and sold at cost to members of the club.
As i was very inspired by Kieran's Stryker when i first visited the club several year ago and had to have something similar and Strykers at the Time where pretty much hard to get hold of anywhere in the world.
So The Funjet from Skyartec was the next best thing.
I have burnt out many motors testing on the Funjet to i came across the Scorpion motors with 200 deg heat threshold and being able to push the motors max current specs to double its specs say and have no problems at all running.

As for Motor sizes and setups you thinking of with these motors -
2300kv - 7x5 or 7x6 prop - 60 amp - 80 amp esc 3s Lipo
2300kv - 6x5 prop on 4s - 80 amp speedy
3200kv - 6x4 or 6x5 prop - 80 amp esc 3s Lipo
3200kv - 5x5 prop if you decide 4s setup

My Standard Funjet Setup was 3595kv - 6x5 prop - 80 amp Esc max Current on Full Throttle 63 Amps 3s lipo, 180kmh level flyby

My Hot Rod Setup Was 1900kv 7x7 prop - 200 amp esc - 6s lipo 255kmh level flyby

Currently Stryker Setup I'm Using Is 3595kv - 6x5 prop - 80 amp Esc on 4s Drawing just over 80 amps full throttle.

Here are Some additional old Pics That i Found that i don't think i posted on this thread.

P.s Secure your Canopy Lid or you will lose it in Flight, secure as well the Lipo inside, re glue your motor mount and brace underside motor mount.

                       

http://www.skyartec.com/Product.asp?BigClassName=Spare parts&Smallclassname=Skyfun Spare Parts

P.S Some Online Threads you may not have seen and may give you some more insight.

http://www.hobbyking.com/hobbyking/forum/forum_posts.asp?TID=5889&KW=sky+fun&PN=1

http://www.rcgroups.com/forums/archive/index.php/t-1163654-p-2.html

Steve Smile







RE: Skyartec Skyfun Thread - secant0give - 03-05-2011


Thanks fo the excellent advice !!
I've a few more mods to do then

Cheers

Jason

RE: Skyartec Skyfun Thread - secant0give - 17-05-2011

I noticed a fair bit of a vibration when I get the motor to about 3/4 throtel, I know it's reving pretty hard and you've got to expect some vibration. I did balance the prop nicely with a magnetic balancer and machined a new prop adapter, one that is dead true and a nice fit on the motor shaft. but still the nasty vibes persist.
I took the prop and adapter off the motor and checked the shaft with a dial guage and it runs true enough. When I rev the motor with nothiong on the shaft it still vibrates when the revs get up there.
Just now I've pulled the bearings out and will replace them with new ones from bearing industries tomorrow. The back bearing looks to have a little more slackness in it than the front one. Wether this will fix things or not I guess time will tell. The bearings seem to be a nice fit on the shaft and not too bad in the housing, the front one is neat needing a lite tap to get it out and the rear one slides in and out pretty nice.



RE: Skyartec Skyfun Thread - gbanger - 17-05-2011

You are probably on the money with the bearing change Jason.
After my PC9 dissaster I striped and checked the motor and bearings and they seemed and felt OK.
But during the first flight it developed a bad vibration at higher RPM that really affected the performance big time.
I purchased and fitted new bearings and now it is as smooth as silk.
Gazz

RE: Skyartec Skyfun Thread - samste - 17-05-2011

Could be Bearing issue,

Common Causes are -
1. Prop Adaptors bent and not fitting on shaft straight.
2. Prop adaptor itself
3. Props are not always what they seem, they may be fine up to half throttle but when you give it goes way out of balance.
( i went through about 3 to get a good one)
4. Shafts not straight


Steve

RE: Skyartec Skyfun Thread - secant0give - 19-05-2011


The new bearing have improved things a lot
I took it for a quick test flight this arvo just before the sun went down
It seemed to go nicely.

It certainly is a hoot to fly with a 4S pack and that APC prop

RE: Skyartec Skyfun Thread - stillflyin - 19-05-2011

Good idea not to change the size of the elevons. Last Sunday I launched Ron's Skyfun complete with double width elevons. He was flying quite well but suddenly there were about 10 other planes up and he handed the transmitter to me because he lacked confidence in such a sky. He said have some fun with it. It was great to fly until I decided to do a fast low pass. Called the manouver and dived for the run. The result of increased speed was violent flutter in one of the elevons to the point of vibrating the strengthened canopy hold downs to breaking point and the canopy blew off. As it went it hooked into the elevon servo leads and separated them from the extension leads so now no directional control. Just shut the throttle down and watched the last 10 metres of the dive. Long grass and mud proved to be a good thing as there was no impact damage. The servo connected to the fluttering elevon is history though. Lesson learnt. If you want to improve slow speed handling by increasing the size of the elevons, then fit bigger new servos ensuring no slop in the control surface to servo connections. Little counter balance weights to the rear of the elevons a-la full size practice would also help but maybe not practical on a belly lander.

Live and learn.

Cheers
John H


RE: Skyartec Skyfun Thread - secant0give - 20-05-2011

Thanks for that John good advive, I was pretty carefull with making the new elevon's, they are wider than standard by about half again, the tape hinges I used are pretty bullet proof and the elevons are nice and stiff being carved from solid balsa, they also fit the shape of the airfoil and are tapered in thickness towards the tips. this took a little effort with the razor plane but they don't flutter at all even at flank speed. Oh and I did change the servo's to more powerfull ones. I used the original servo's on my new depron foamie.

RE: Skyartec Skyfun Thread - gbanger - 20-05-2011

Another thing you can do stop over control which causes elevon failure on the Skyfuns is to set your elevons up with dual rates.
I take off and land with my servos set at 100% but once airborn and approaching silly speeds I switch over to 40% . It makes the aircraft alot more predictable but certainly not docile at silly speeds.
Over control of the elevons at silly speeds is more than likley the cause of that type of failure.
Gazz

RE: Skyartec Skyfun Thread - samste - 20-07-2011

I thought i would Resurrect my Skyfun Funjet with a new Look.
All balsa Elevons and Ruddered up, Just missing is Motor ?

           

Steve Smile

RE: Skyartec Skyfun Thread - samste - 20-07-2011

Motor Installed and Ready To Fly.

           



Steve Smile



RE: Skyartec Skyfun Thread - samste - 21-07-2011

Was Toying on the Idea of installing Wing lets to the Tips of my Sky fun for more Vertical Stability what ya think plane build experts ?

Some Pics of what I'm thinking of, with the mini CD on end it gives both upper and lower stabilizing yes/no and may help with vertical drops ?

           

P.S the Winglets are off my Viper Build which i'm not going to use, i will need to make some or buy them if possible they sell them as spares but i doubt it.
But they do Look good on the End though.

RE: Skyartec Skyfun Thread - secant0give - 21-07-2011

I don't knOw if it needs more lateral stability mine rocks side to side just slightly as it is. Probably a sign that it's over stable. Tho winglets wold reduce drag a little and that Maens a little more pace

RE: Skyartec Skyfun Thread - kizza42 - 22-07-2011

The Cd's will help you knife edge but they'd be better placed in front of the motor along the centerline
You want the leading edge wing fence and wing root slot to help with Stryker Q vertical drops.
I don't advise it with a skyfun, too heavy