Rather be Flying? You Betcha!
Why? Cos its heaps of fun, and
I forget about my problems while flying a model as
it takes all my concentration to stay up with, or be a little ahead of what's happening!
My main interests for this
year (2007) will be helicopters, both electric & glow, and water-planes,
and keeping this page up to date will encourage me to make progress!
My heli adventures started a few years ago with a GWS Dragonfly which was a complete waste of A$395!! I just found the original invoice, and was staggered at the cost. I continue to try and get it to fly, and managed a 20 second staggering flight after replacing the GWS 3 in 1 unit with a s/h Colco 3 in 1 unit recently.
I have several cheapy helis lying around, but the big breakthru came with the purchase of a Blade Cx2, which really is ready to fly out of the box after running the checks from the manual, and charging the flight battery! Being a twin, contra-rotating rotors machine, it is easy to fly, and will be a good training heli to get accustomed to flying around before venturing on to a conventional tail rotor heli.
Here is a Colco Lama (after mods) which is a great machine to fly, and cheap too. A Blade Cx2 has just landed on the spot in the centre.
The Blade can be handled in tight spots too!
Seaplane projects include a GWS Formosa on floats, a TM400 to fly on the same floats, and a Seamaster with both electric and glow power pods.
Waiting to be built are a Pilot Lake Buccaneer, a Laker, and a Northstar. But a Coot electric ARF amphipian is on order for the sheer convenience of electric flight.
I have since found that I need to lower the front of the floats, take-off's are a wet affair till it gets moving!
A Blade Cx2 problem or two......The wind picked up a bit while I was flying outside one day, so I landed. It was a bit rough, and I broke an upper and lower rotor blades.
So I replaced the bades, but got vibration, and it would only climb slowly.
The verdict was that I had bent an outer shaft, so I replaced it, and it was just the same! So I replaced the inner shaft too......no change again!
As it was still vibrating with new shafts, I was scratching my head for a cause. Tracking seemed fine, but maybe the rotor blades were out of balance. A quick check weighing the blades on reloading scales showed the lower blades were mis-matched by at least 10 grains! So I weighed all my spares and selected the best matched pair. This time, the vibration was gone, but it still wouldn't climb higher than a few inches! Aha, I had worn out the motors.....not much life in them eh?! So I replaced the motors, expecting orbital performance. No change again!
This was taking most of the afternoon, and as we were puzzling over the problem, one of my friends was checking the blades, and pointed out that he thought that a bottom blade seemed to have a lot less pitch than its opposite blade. Closer inspection showed that there was a LOT less pitch on that blade! So it was replaced with one of closest weight, and pitch more like the other blade, and that was the solution! She's flying like a ripper again! So there are some things to watch for on the Cx2....balancing the blades, and checking the pitch. I suspect that the blade was bent in storage. I will try some heat gun treatment on it to restore it to normal pitch.
Although I have seen various comments about this brand, I have just started learning to fly this machine, and it will be a long process. I was encouraged to see a lot of videos on YouTube of these flying successfully. I have made training gear for it, and can almost control its shuffle around the floor! I suspect that the NiMh batteries I purchased with it need cycling as their life seems to be limited. I'll look for a LiPo that will fit it for longer attempts. It is very twitchy, and completely different to the Blade to fly, as indeed I did expect from previous Dragonfly experience. But the gyro actually seems to be helping in this case.
Later. I now believe that the battery packs that I bought with it are junk, and I'm lucky to get 1-2 mins useful power from them. A 3S LIPo 1350mAHr is far more useful, so I'll get more of those. The training gear has saved me from breaking parts of the heli for sure. We can now hover inside a square of 2-3m sides. So the heli can fly better than we can anyway!
The trainer gear was built for 80c, 4 table-tennis balls at 20c each! They gave me the 1/4" dowell. Absolutely essential to save breaking parts! I attach it with rubber bands. Only fly off a smooth surface though, not this patch of ground.
More progress reports as I continue, with a pic or two.
Coota, also known as Hybrid-Air
The Coot finally has arrived, so here are my comments on this model. Overall, it is a well made model, with the complex shape reproduced by craftsmen. And, although mine has only had one flight, I can say that it flies well. I expected a long take-off run, but it leapt off the ground in a few metres, although some down trim was needed. Mine is the 7 cell NiMh version, and although it is a new battery pack, it seems to be plenty of power. Not a beginners model to learn to fly though. It is similar to the GWS Formosa, but a bit more twitchy, depending on the CG location.
The first problem that I noticed was that there was a magnet missing from cockpit area which was one of four which secured the canopy. I had a discarded piece of cutter blade which I ground to fit the area it was meant to fit, and fixed it there with GWS foam glue. You can just see it in the pic below near the right-hand edge. It holds the canopy well, but I will be glueing some strips of foam along the bottom so it floats in case it gets knocked off while on or over the water.
My next problem was that although I looked thoroughly in the Manual and on the epoxy tubes of glue, I could not find what time the glue to took to go off. So I just did the best I could as there is quite an area to cover as well as the spar well. The first wing went well, but I was nearly caught by the second wing. I spent too long ensuring the glue was everywhere it was needed that it had started to cure, and I had a hard time pushing it into place. It is slightly mis-aligned which disappointed me, but it appears to not affect the flying qualities. But I know it is wrong! Some information or a warning here would be nice.
While talking about the manual, I must say that I am again disappointed that there is absolutely NO technical information in it! Nothing on range checking, or the ESC, which beeps 5 or 6 times on switch on. It is only an airframe assembly manual. It is most annoying to not know what the ESC is asking for.
Moving on to the battery mounting method. A flat piece of hardened foam glued to the hull stand-off ribs is supplied to band the battery to. Two rubber bands, doubled around the mount, are supplied. As soon as you try to lift the bands to insert the battery, the foam floor breaks away! I re-glued it, and fitted velcro-type ties to hold the battery, but its better to fit the ties first! I put a thin line of blue-tac on the mount to sit the battery on so it doesn't move fore and aft, but the foam spacer is fine. The rubber band idea was crazy. Much too tight to hold the battery. A single turn might have been ok, but this way I can adjust to either the NiMhs or LiPos. Keep the NiMhs well back, and LiPos as far forward as possible to avoid adding noseweight.
See note below re control difficulties when the ESC killed the motor!
I did the classic when under the influence of the excitement of Maidening a new plane, and although I planned to, I completely forgot to range check the radio when it was sitting on the ground ready to go!
So, after the successful maiden, I figured I would see what the antenna-down range was for future reference.
So I paced out around 20-30 metres, and eveything was fine. As I was returning to the plane, the servos started jittering, but I thought it was my friends plane. We soon found that it wasn't, so I changed the Tx batteries from the alkalines supplied, to known fresh charged nicads. Now I had about about 10m range with the antenna facing the plane, and nothing facing away! Then it dropped to about 5m range as we were talking about it. So Coota was put away for the day! I need to check if the transmitter or receiver is the problem, and should be determined reasonably easily. It's a pity that the Coota can't be bought without radio gear. I will post the results of what I find. Quick guess....I wonder if the transmitter did not like running with the antenna down, and heated up the output stage, and started to shut down, getting worse with time as we were testing?!
UPDATE - I just found that any combination of transmitter and receiver will perform the same way, so I wonder if the antenna being inside the Coota puts it too close to the ground, causing problems.
I will continue checking, but with the model a metre or so above the ground. And taking long walks with the antenna up to note the actual ground range. Air range should be 3x the surface range. More soon.
BUT, during the tests, the elevator stick tightened up and now will not return to neutral without help. So this radio needs work, and could end up in a slopey.
Checks show that with a Align receiver in the Coota, on a card table on a slight hill, I get around 140M ground range with the Eclipse Transmitter, both broadside and facing toward the transmitter. Slightly less with the Optic tx.
UPDATE - Subsequent tests show that I get around 140M ground range with the micro single conversion receivers, an Align and the one supplied with Coota. The Futaba Skysport 4 gave 300m, and Hitec Dual Conversion 360m. Air range should be around 3 times that distance. BUT, it was interesting to note that when I lost the signal, I had to return to almost half way back before the receivers would respond properly again! A big trap if you are flying out on the fringe, and lose it. This may explain at least one of my crashes recently. I had not noticed this effect before.
CAUTION - I have flown the Coota many times, but last week, the ESC switched the motor off suddenly. It was so bad to control that I thought the ESC had shut off power to the RC gear. It ended in a semi controlled crash, but is quite repairable, fortunately. After returning to the bench I saw the radio was still working, so the plane must need special treatment if ya get caught dead-stick.
I will be ready in future, and shove heaps of DOWN in, and also remember to kill the throttle, then bring it up to low revs to help with control-ability, and land IMMEDIATELY while still having some control. It really needs power to fly all the the time.
Now I'm off to try and finish this project.....
I answer questions, so send to this address........