Parramatta Radio Control Aircraft Club

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Hi guys, purchased a mini angel glider at penrith club swap meet & have been searching internet for a suitable motor, speedie & folding prop to match. Plane not featured on many sites but specs found on http://flight-model.en.alibaba.com/produ...erproduct1 . Any assistance will be appreciated. Plane has a flat nose & appears to want a front mount for the motor with the shaft protruding thu the nose. 35mm outside diameter most suited.

Something like these might well do the trick

how heavy is it ?

http://www.hobbyking.com/hobbyking/store...oduct=8486

http://www.hobbyking.com/hobbyking/store...oduct=2139

http://www.hobbyking.com/hobbyking/store...duct=16092

http://www.hobbyking.com/hobbyking/store...duct=14342

This one will have a bit more power and is rated to run up to 6S but it's a little heavier as well
http://www.hobbyking.com/hobbyking/store...oduct=8485

I'd be looking at grunty ESC like these ones

http://www.hobbyking.com/hobbyking/store...oduct=7340

http://www.hobbyking.com/hobbyking/store...duct=16366

and folding props to suite may be found here

they will be different depending on which motor you go for

http://www.hobbyking.com/hobbyking/store...tegory=208&curPage=2&v=&sortlist=&LiPoConfig=

Hope this helps


Thanks Jason,
Some worthy suggestions , some on backorder, might order a few motors in stock, not all that expensive & can leave unused as spares for future or individual tryouts for performance.
Would love to find a site that will give calculator for weight/motor/esc/prop suggestions.
Anyone had experience with this stuff?....

http://www.rcfoam.com/product_info.php?cPath=180&products_id=1246&osCsid=c5888dd5d8eb2cee83b817c6644cd27c
No I haven't Steve..... you can be the bunny.
I don't have any first hand experiance with this
but I have read a few posts on rcgroups discussing this or
something very similar to this. Results were mixed,
Don't think enough people have tried it yet to gauge
a definate opinion.
Does anyone know where I can get Loctite Hysol 9462 Epoxy adhesive in Australia???
Just a little something I was not aware of that I discovered on the Instructors Course.
Did you know that you can buddy system between Mode 1 and Mode 2 or any other Mode for that fact. Just something to keep in the back of your minds. Obviously for student familliarity it would be considerably beneficial if you both have the same radio. Thats one of the reasons I am going to buy a student training aircraft.
Gazz
Yes mate - my instructor (Junior) is mode 1, but my brain is wired up the other way on mode 2.
We both have DX6i transmitters and sure enough, the translation is complete with an ordinary buddy cable. It used to work perfectly!
Been trying to tell you guy's for years
The ony problem is the students radio is the master you have to re bind so the instructors radio becomes the master, otherwise your modes are arse about during flight. Stay tuned for more "I already knew that shit" from Gazza's school of friendly but hopefully helpful suggestions.
OK Its been one of those weeks and the old grey matter is a not quite with it.
I need 8S 5000mAh for my L39, I know when you wire them in series the voltage doubles and the amperage remains the same and if you wire them in parralell the voltage stays constant but the amperage doubles so before I order the wrong batteries.
Do I wire 2 x 4S 2500mAh batteries in series or 2 x 4S 5000mAh batteries in series to get my to get my 8S with 5000mAh.
Was going to order the batteries this afternoon but then I thought hang on a minute????
And now I have confused myself. !!!!
PS: Please don't answer this question if you are as confused as I am.
You need 2 x 4S 5000mAh Gary.
In series, 4s+4s x5000 = 8s x 5000
In parallel 4s x 2500+2500 = 4s x 5000

You want to buy 2 of 4s x 5000 to get your 6s x 5000
What alternatives are there for CA hinges?
Can't find any at LHS.
Floppy disks?
(08-09-2011, 02:53 PM)Drew Wrote: [ -> ]Floppy disks?

Ay????Confused
Iv'e got a truck load of these if they will suit your build Pete
http://www.hobbyking.com/hobbyking/store...0pcs_.html
I have been using these things in a lot of my aircraft for a few yearnow and they are easy to use and much stronger that CA hinges.
I have large and small ones if they will help mate.
(08-09-2011, 04:47 PM)gbanger Wrote: [ -> ]Iv'e got a truck load of these if they will suit your build Pete
http://www.hobbyking.com/hobbyking/store...0pcs_.html
I have been using these things in a lot of my aircraft for a few yearnow and they are easy to use and much stronger that CA hinges.
I have large and small ones if they will help mate.

Cheers Gary but i find they leave to big a gap between the surfaces.
The CA allows you to almost butt the two together.

I have some of those and the fixed pin hinges aswell, but i'm after a closer fit.
Your not installing them correctly if you have a gap. The ones I have installed give me a gap if less than 0.5 mm
(08-09-2011, 05:17 PM)gbanger Wrote: [ -> ]Your not installing them correctly if you have a gap. The ones I have installed give me a gap if less than 0.5 mm

hmmm, i have tried the standard hinge type which gives about 2-3mm gap, i'm now stuck with a slot cut into the wing and aeileron. hence the first thought to go back to a CA hinge.
May need to drill a hole and give those suckers a try.
Hi all,
A couple of questions on BECs ...

1. What's the difference between a UBEC and an SBEC? (I presume the 'S' means "switching" but who cares? - what advantage does a switching BEC have over a linear mode one anyway?)

2. Amoungst the BEC options HK offers, can anyone recommend a good 5A output option that they've used?

Cheers,
Steve
Cant recommend any of the HK ones mate because I haven't used em.
But almost all the guys with big helis use these and I use em on my big aircraft for stand alone Receiver power. They are made buy Align so not much needs to be said there. They are 6 amp constant supply have leds on the side that show you the state of the battery supply and have an on/off switch on the side. For the price not much else comes close.

http://www.zeejayhobbies.com.au/electric...d_334.html

Gazz
Thanks Gazz - those ones would be a quality unit, no doubt about that - but by the look of the specs, you have to carry a separate 2S battery for it.
I was looking around for something to run off my flight battery but could deliver enough current for 9 servos, which would be beyond most of the built-in BECs.
I might have to do it properly with a separate battery, but trying to avoid it.
Cheers,
Steve
Steve,

SBEC and UBEC are the same beastie design-wise. Both are switchmode.

Linear v Switchmode - Linear input is pretty darn reliable by design but work at retricted voltages and lower efficiencies. You need to get one that suits your set up (3S, 4S, 5s, etc). Switchmode operate over a wide battery voltage range (2S-6S) and allow freedom for battery upgrades - but the switchmode is less reliable than linear (but I not saying they are unreliable).

I actually use the BEC output from ESC in my Logo. It is internally independent of the motor electronics (15A output) so the only scenario that would leave me in deseparate trouble is a total battery failure. I guess that is possible but you can have that happen on independent power set-ups too.

There are other options coming through now. You can "HV" rated receivers which allows a 7.2V LiPo to be directly connected (which is 8.4V when fully charge BTW. That is where most guys come unglued when they think "my 2S LiPo is 7.2V. That will work!". No.

The other option being widely used is LiFe batteries which charge like LiPos and have excellent power density but do not have high cell voltages like LiPos. They will sit around 6.6V which means you can direct connect a LiFe pack straight in to your reciever and servos without issue. Very reliable. Lots of places selling LiFe batteries.
Thanks Dave - that fills in quite a few gaps.
I've done some extra reading since that post (yes, got the order back-to-front there) and it seems that the linear implementations also dissipate more power at the top end of their operating range and therefore require a larger heat-sink - which is of course sub-optimal in an aircraft, but probably less of an issue in an RC car or boat.

The machine that I'm presently putting together (see below) doesn't have much space in the fuselage for extra batteries, unfortunately. The reports on RCGroups suggest that it comes with a marginal 50A ESC, so I was thinking of either adding a BEC, or a new uprated ESC, or perhaps both. It has eight servos, which is a big ask for the sort of integrated BEC you'd expect to find on a no-name ESC (not the one you're using, obviously).

I might get one of the HK UBECs that are rated at 5A and do some bench-testing on it to see what it's really capable of. That will give me time to do a new desert paint-scheme on the Stuka beforehand anyway. Thanks again!

[attachment=1686]
Mean looking SOB!
Hi Steve
I like the Stuka always have.
We spoke about the Hurricane last weekend and I noticed a build thread
on RCGroups today. Are youaware of it?
Here is the link: http://www.rcgroups.com/forums/showthread.php?t=1499408
It looks like a great model too.
As Dave says, linear regs are less efficient - the excess voltage for a given load current is dissipated as waste heat (often just a zener diode to clamp the voltage and a couple of resistors).

Switching regs act much like a simple DC motor speed controller - continuously varying the duty cycle, and hence (generally) waste much less energy, with the trade-off being things like increased cost, complexity, EMI etc.

I've got a Turnigy 5A UBEC from HK that you're welcome to. That said, I've been using a Castle Creations 10A BEC in the mini UAV to drive the servos and run the auto-pilot, on the basis that this was much safer than trusting the no-name ESC - retail about $25.

BTW, you probably already know this, but be sure to remove the red/power wire from the throttle/ESC servo plug before plugging it into the receiver when using an external BEC, lest you let the magic smoke out of one or both as they fight each other to regulate the voltage.

Nice Stuka... did it come with "Jericho trumpets"?
(02-10-2011, 08:21 PM)Claudius Wrote: [ -> ]As Dave says, linear regs are less efficient - the excess voltage for a given load current is dissipated as waste heat (often just a zener diode to clamp the voltage and a couple of resistors).
Yes Claudio - tends to match up with the need for larger heatsinks which I'd read about.

(02-10-2011, 08:21 PM)Claudius Wrote: [ -> ]Switching regs act much like a simple DC motor speed controller - continuously varying the duty cycle, and hence (generally) waste much less energy, with the trade-off being things like increased cost, complexity, EMI etc.
Yes - this also adds up, the EMI from the switching would be the reason behind the torroidal chokes that are found on the receiver leads on most/all the examples I've seen.

(02-10-2011, 08:21 PM)Claudius Wrote: [ -> ]I've got a Turnigy 5A UBEC from HK that you're welcome to. That said, I've been using a Castle Creations 10A BEC in the mini UAV to drive the servos and run the auto-pilot, on the basis that this was much safer than trusting the no-name ESC - retail about $25.
Thanks mate, but this isn't urgent so there isn't any need for me to deplete your stock Smile

(02-10-2011, 08:21 PM)Claudius Wrote: [ -> ]BTW, you probably already know this, but be sure to remove the red/power wire from the throttle/ESC servo plug before plugging it into the receiver when using an external BEC, lest you let the magic smoke out of one or both as they fight each other to regulate the voltage.
Yep - not going to be caught out by that one.

(02-10-2011, 08:21 PM)Claudius Wrote: [ -> ]Nice Stuka... did it come with "Jericho trumpets"?
This particular version, the Ju-87G, apparently didn't have them. It was not a dive-bomber, but was fitted with the two (pretty obvious) anti-aircraft guns and turned into a tank-buster on the Eastern front. I have never really been a fan of this particular plane, but its ugly and sinister form have a certain appeal to my ugly sinister side Wink
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