enricong

I also have that fear.

and I use the lipo that I had in a tree over night and expanded.

the charged it back all the way and somehow unexpanded.
I've been using it and havent had any problems, doesn theat up.
it seems to expand alittle though but when I charge it, it will "unexpand".

vega2614

But how long do you typically fly with the battery?

A similar thing happened to me with my Lama lipos; the one expanded but deflated after charging.

enricong

not long, its been windy lately so not more than 5min

GreenAce92

Hey is this cub the same one? I just bought it and if it is the same one i will referr to this forum more.
http://www.chiefaircraft.com/cgi-bin...lScrapBox.html

enricong

that looks the same as the second cub I got. it never flew very well for me unstable. I attributed it to the smaller control surfaces but who knows. It could be anything.

vega2614

Enricong, what's the maximum amount of time you've ever flown the cub with your current setup? What mAh is your lipo again? I'm just trying to compare my 2410-09 motor with your properly working 2408-21T.

That cub should be pretty similar Ace, so most of the info on this forum should apply. It might be made more poorly though, like enricong said.

I flew again today (dusk flight) with the 2410-09 back on there. Not as much speed, but the cub was flying well despite gusty winds. I got it up about 500ft a few times and did some aerobatics. Loops were still a breeze. I did some inverted flying, but honestly I'm not very good at it. The plane doesn't seem to stay level inverted, but I think that's because the rudder is off, so maybe that has something to do with it. Even with full left trim, the plane veers right, when right-side up. I also was able to pull off some nose-dive barrel rolls. They looked like a normal aileron barrel roll, only the plane wasn't flying level. A couple times the plane rolled like 3 times in a roll really quickly. I wish I had some footage. I was afraid the plane was going to rip apart.

I think I'm going to try and get a camera to mount to the cub. I'm ready for some in-flight footage.

enricong

probably 2-3min because I havent had a chance to fly it much yet.
Of the flights I've had, it has either been too windy, stuck in a tree, or the tail fell off and I had to do a "corkscrew landing". It still is not perfect and has that left roll issue

I use a 1300mah, mainly for nose weight.
I still have to work out the angle of the motor so its down more and to the right.

Also, the other cub is probably ok, I blamed iton the design but I have no idea, they look almost identical except for the control surfaces. It was most likely due to my flying or winds or something.

GreenAce92

Is this cub the same size as the Pkz J3 CUb. I have some spare tails and landing gear plus a motor. My Pkz Cub is grounded at the moment after hitting a powerline and popping my battery must have been a power surge or something. It was quite funny though to see a cub spinning around a powerline round and round like one of those fireworks that you mount on a spinable platform and it circles round and round. Do you guys think this thing can fly right off the box or do you think i will have to do some modding and also do you guys know what the Tx looks like?

THanks. I will post pics and tell you how good it flies should come in tomorrow it says predicted shipment arrival 7/25/07 but im hoping it comes in tomorrow.

AJ1202

GreenAce the PZ cub is just a tad bigger I think, if the SD cub is what you have coming then it will fly right out of the box but it will be tailheavy and should be corrected before the first flight, if not disaster will follow, she is bad to stall when tailheavy.A simple mod to move the batt into the empty comp behind the motor will solve the CG issue. Do you know if the one you are getting has a geared motor set up or direct drive. Personaly I think the geared set up flys better because you can use a bigger prop and get more thrust

enricong

a power line? wow.

I used a Lai Shing cub http://www.nitroplanes.com/3lsj3picubra.html
if you look closely you can see a few slight differences.
The cowling lookes different and attaches directly to the side of the firewall.
The tail control surfaces are also slight larger.
It comes with a four channel controller.

Overall, compared the the SD cub, I find that the SD cub is built better. The cowling attaches better and the overall construction is of higher quality. However in the end, I had the best LUCK with the Lai Shing cub. I say luck because I have no way of knowing why

GreenAce92

I think its geared. Wouldnt attaching a larger prop take more amps? Well i guess for 40$ it might not be too bad of a buy cant wait when it comes in. Ill see if i can fly it without hitting powerlines, Grapefields or trees.

rjeshleman

Just helped an elderly friend get his first flight with the Piper J8...radio is mode 1....rudder on left, elevator on right. His battery pack was a dud to get started...Ir is hard to find around here...
I need a reasonable source to purchase 600 mah or more, 7 cell AAA paks for in the plane. It flew well however the pak I found was only 250 mah...not a very long flight. His ox is marked SDM?
RJ Eshleman

AJ1202

Cheapbatteries.com has good prices, I would go up in ma though, you can use the extra weight to help ballance the plane, I flew mine with a 9.6 1050 batt
When I say use a larger prop I just mean the prop for a geared motor is bigger than the one for a direct drive ie, direct drive you don't want to exceed 7X4 or you risk burning up your motor and on a geared you can easily use a 8X4 and it fly well. the standard prop for a 380/400 direct drive is 6X3

GreenAce92

Whats the Pkz J3 cub's prop size?

enricong

the two cubs I got were not geared

vega2614

I think for the $40 you will get your money's worth. Although I didn't mod the battery location until after a couple months of flying, AJ is right, it makes the plane fly a lot better when you move the center of gravity (CG) forward. At first, the cub flew like someone was pulling on a string attached to the tail.

I got my 8.4V 1000mAh NiMH battery from bidproduct.com. Shipping takes forever, but I got the battery for $10 total, and it helped out my CG issues. I used an 8x3.8 prop on the cub, mainly because my stock was 7x3 (or 7x4, still not sure). My 380 no longer works like it used to (very low thrust, max throttle barely kept the Cub flying without stalling), either due to overstressing it with the large prop, or repeated nose crashes that bent the shaft.

I think most cubs are not geared, except for the PZ one.

enricong

mine came with a 6x3, I switched to a 7x4

I had the same issue with my 380 motor, that is why I changed to the brushless

AJ1202

Green the stock prop for PZ cub is 8X4
stock prop for SD cub direct drive is 6X3
stock prop for geared drive is either 7X4 or 8X4 depending on who boxed it
running any prop bigger than 6X3 on the direct drive motor will cause early failure
but the direct drive offers very marginal performance anyway so I say push it till you kill it then if your plane is still intact upgrade it .
Right guys

The Cub is a great flying plane, sadly most come with a stock power system that will barely fly them, so if your skill level is still in the beginner stage the plane most likely won't make it for long. I destroyed my first cub before I learned this lesson, the second one I upgraded and flew for a year before giving it away in perfect flying condition, with a aileron mod done to it.
The ole eyes aren't what they used to be and the cub was just too hard for me to keep up with

enricong

I flew my cub great. I was able to do loops, inverted, even a psuedo-barrel roll.
The only mods were moving the battery to the nose and switching to a 7x4 prop.

My motor started heating up alot after it nosed in a few times. On one occasion, the shaft was pushed in and woudl not turn. I pulled it back out and it started working again. The shaft was also bent. I beleive that is what caused my motor to have problems.7x4 and 6x3 are pretty close I think.

vega2614

Yeah, it was the same for me. The cub was way underpowered, but it did fly well enough to do loops and inverted flight for a while, until the motor got worn out. I started with 2-channel planes first though, so that helped me get used to RC flight. Keep in ming that both enricong's Lai Shing Cub and my Harbor Freight Cub aren't necessarily the same as the Shun Da version. They're pretty similar though, so I can't imagine there being a huge difference. It did always seem like the Lai Shing had more power from the vids, but I'd probably have to fly it to know for sure.

GreenAce92

Yeah i hope everything goes alright when i fly this plane. I bought a high pitched prop for my Pkz J3 cub and it was so unstable the whole plane was shaking in my hand. I put the stock prop back on and it flew nicely.

enricong

just had a flight with the CVS camera in the cub.

plane still acted tail heavy eventhough the CG seems like it is in the right spot. perhaps the motor is just too powerful. Tried to get high and fly level. at one point it looked like I was getting servo chatter so I got lower.

http://www.youtube.com/watch?v=kBtCOAoylRg

GreenAce92

Cool vid. Is this the SDM pipercub or Pkz?

enricong

LaiShing Cub, see my message above, I have a link

AJ1202

Enricong, are you having to add down elevator to get it to fly level. It sounds like you still just don't have enough down thrust, I know on mine when I got it right the motor looked like it was facing the ground, did you try cutting throttle and seeing if it levels out. One thing though the plane will fly with the tail down just a hair and be OK, if you realy are tailheavy the plane will sort of waddle at the tail, just sort of swing back and forth trying to get the needed lift to settle in
Try to remember next time out to get it up and going at WOT then cut it to zero and watch the plane, if it noses down your thrust is too high, if it noses up your thrust is too low, if it stays the same then your right on, also trim it to fly level at 1/2 throttle, then it SHOULD climb when you throttle up, that is how you want it to perform.
Oh cool vid