RC Planes

Yeah, I thought it might be opening a can of worms. :p I'll try and digest that later - I'd be interested in the website you refer to. When I first started looking at this stuff everything looked complicated, and the more you look into it... the more complicated it actually is. :eek:

I got my 808 #16 camera through the post today. Thought it was coming from China but it actually came from Switzerland, which must be why it only took a couple of weeks. I've got a 4gb card for it, and after just a few test videos it seems to eat up about 1meg/minute, so I've got an hour. About right considerin the battery only lasts 40 minutes.

Annoyingly the camera inside isn't quite lined up with the case. It points dead ahead, which some apparently don't, but it's on the wonk from left to right, so I'll need to make sure I mount it properly to get a level view. Might be a bit finnickety.

If I can get out in the next couple of days - looking out it seems the weather is taking a turn for the worse - I'll get some videos up. :)
 
alexthecheese said:
I've been doing a bit of reading before work on the old props/motor/thrust/amps/watts combos out there, and it all seems a bit open ended. Basically not as simple as I hoped. :p
Click to expand...
electric motors work like this
the higher KV = faster the motor is but the less torque it has
the lower the KV = the slower the motors turns but the more torque it has
you also get different "poles" 2 pole , 4 pole , 6pole , 8pole etc
pole = magnet , the more magnets the more torque

i think all heli/plane motors are 6 or 8 pole

3800kv =rotations per volt

11.1 volt X 3800 = 42180 rpm etc
 
Best to look at what others are running and emulate, I got my setup from RCpowers forum:

2800 kv with a 6:4 prop on a 30a esc with 3s 2200mha batteries and gets my hawksky really high rather quickly. but at 50% its perfect for stunts with power to pull out.

With my park flyers its a 2600 and 28a esc, same batterys and props. More than enough to 50% throttle around doing stunts with both. 50% throttle is a must with electric flight, everything lasts a whole lot longer.

when I was specing gear for my spitfire I worked out what prop I wanted first(so it looked scale and threw enough air) then matched the motor to the prop and batteries(3s) then got an esc that was man enough to cope.

remember sticking a bigger motor on means bigger batteries which means more weight. You may find u get better flight times by running a lighter set-up. Mate had exactly this with his dual battery su27, 5 mins max flight time.. as soon as he used 1 battery he pretty much doubled his flight time as his all up weight was less.

Id also look at running a ubec if ur getting serious powers going though the system... or what about running a 2s for your radio and servos and a 3/4s for the motor. Dont forget the cooling for all the electronics too.
 
All my bits have turned up today so I will get on with getting them ready for flying. Busy this weekend though so no flying for at least a week now. Handy getting batteries with Deans connectors on from factory for once!
 
Ok, a little update titled "Bugger". :p

img9886o.jpg

By alexthecheese at 2012-02-23

img9887ki.jpg

By alexthecheese at 2012-02-23

Got my little video camera on it so managed to get some footage, but all the way through the first flight - lesson learned here - it was constantly banking to the left, despite the trim set full to the right. Maybe it was the batteries shifting to one side, or something else I didn't spot, but I repositioned the batteries for the 2nd flight, it went up, it banked left, it was 90 degrees to the ground and smacked into the floor.

A fairly large chunk has come off, which I have, and my camera went flying. Found that also, thankfully, so I do have the bit of footage that I didn't manage to get.

The insides are a bit battered also, the batteries ripped through the wooden structure inside that I was using to hold the batteries in place. Thankfully the rest of it is alright - the fuselage is fine, and the other half of the wing is also OK. The elevator has had a small corner knocked off, but I'm not worried about that.

So... now to repair mode. :D What glue can I get? I am figuring that with some appropriate glue and some new stiffening rods to bolster the wing back to full strength. Anything else that would work?

The only real issue is that the aileron has ripped away from the plane - not sure how I'm going to fix that. Hopefully you can see on the 2nd image that it's a single mould and it's pressed in a line to give the hinge. Perhaps some kind of tape or some such? If I can get the wing tip back on and sorted that will be the only thing that prevents me from returning to the sky.

Shoddy youtube clip (just uploading) from what I did get. Nice close up of my nuts at the start. Didn't realise I had a rip in my jeans there... LOL. I'm sure you'll all enjoy that. :D

Also hopefully it'll be able to fix the stuttering in the file... I'm using the AVI firmware rather than the MOV firmware (to get it into VirtualDub) but it produces annoying stutters throughout. :o
 
sounds to be like balance was out after you put video camera on it, or of course like you say your batteries moved in flight perhaps.

As for ailerons, I don't quite 'get' what you are saying. You could rip them off and get some balsa wood and make some new ailerons, cover them and use tape along the whole trailing edge for the hinge system.

Glue wise. There is a good one made by UHU, you need a specific one though otherwise 'some' can melt through certain types of foam/plastic/polystyrene.

Fixing it is all part of the fun at times.


All a learning curve
 
What I mean is the ailerons are ripped from the wing, but they're actually part of the wing. So I'm not sure how to reattach them, or fix where it's ripped away.

Here's a Youtube clip - two touch downs! One that glanced the floor - 3:53 completely unintentional but was well chuffed. :D

The second (5:22) was so hard at the floor it bounced back up another 10 feet before it fell back down again. Not even sure why I managed to hit the floor so hard, maybe something had moved in and around because it did decide to go down and not want to go back up. :p


Go to 32 seconds in if you don't want to start at my crotch for 30 seconds. :o

Here's the actual wing-destroying crash. It stops just before but you get the idea of what is going to happen. ;)

 
Last edited:
hot glue and toothpicks is all u need to repair that... amusing u have all the bits.

edit:
oh and clear strapping tape for the hinge like this use so the strands are in line with the hinge

if ur missing a bit of foam i can send u a section of depron to use as a new control surface
 
Last edited:
It'll fix with cocktail sticks and epoxy. :D I snapped a wing in half and put it back together with that method, just spike a 3 or so cocktail sticks into the end of the foam half in, then push the other half onto them, then with epoxy to glue together. Not the prettiest but it has worked for me.

It's all good fun, if crashes bother you then it isn't the right hobby for you. :D

Personally I would cut both ailerons out then get some hinge tape (3M Benderm works well, it's what I use) to reattach with. Fold the aileron 90 deg from the wing and attach the tape on the outside between the two, then do the same for the opposite side. This will create a really flexible hinge.
 
Surgical tape saitrix?! That is really expensive stuff!! I think I'll try the clear packing tape. :D

Thanks for the replies. It doesn't bother me crashing and having to repair, I just want to know why it went like that in the first place. It must've been because of the batteries moving about.. it's never been quite right and I think I've paid the price.

Also being impatient as my Dad was there and I was feeling rushed to get it up in the air. I think I'll go by myself for a bit until I'm a bit more experienced.

I did think about cocktail sticks actually - I'll give that a go. I have contact adhesive, is that any good?
 
Alex, looking at those vids it appears to be all over the place as you seemed to be fighting it looking at the low level passes.

Was the centre of gravity correct? Tail heavy is very bad.

Was it trimmed correctly?

Did you have some expo to help soften centre stick?
 
Magic_x_uk said:
pack the batteries in tight with foam if you have too so they do not move around.
Click to expand...

That... is a very good idea. I'll do that. :cool: I am thinking of removing the front wooden structure within as it only serves to make things more awkward. If I can sort roughly where the CofG is, I can stick in some foam inside and then use some spacers to allow it to be positioned depending if I have anything on the nose.

Pred said:
Alex, looking at those vids it appears to be all over the place as you seemed to be fighting it looking at the low level passes.

Was the centre of gravity correct? Tail heavy is very bad.

Was it trimmed correctly?

Did you have some expo to help soften centre stick?
Click to expand...

Yeah, I was fighting it all the time actually. :o The first time I went out it was easy, really relaxed flying. I trimmed it up and when flying along it didn't take any movement at all.

Thinking about it, would it be the motor? After the old one ejected itself from the plane, I put a new motor on it. I managed to fark up the shaft and introduced some play into it. So it's off balance. It still gives plenty of thrust and doesn't shake like crazy, but could it be that?

Alternatively it is just the CofG and I just didn't pay enough attention to it. Doh. :(
 
You must log in or register to reply here.
Back
Top Bottom