Friday 30 May 2008

Flying Day Tomorrow

Going out flying with another helicopter buddy tomorrow. Might get some phots and or some video. We will see.

I flew a bit today (I try to fly everyday if I can) and I took the weights out of the flybar paddles. I had full weights in there before. The Roll and flip rate has gone right up, but it i a little unstable. I had the Protos in an inverted hover and it was a bit of a handful. I am running 1/4 weights on my 450. I hoping that 1/4 will be right for this heli too. I want quick roll rates but not be too unstable. I will probably create 1/2 weights too and take those with me to the feild just in case.

Wednesday 28 May 2008

Protos - First Real Flights

Ok. I have had the Protos out for a few flight since sorting my static problem. It has been a dream to fly. I love the way the Protos sounds as it spools up. Very quiet. Just air being slammed out of the way.

Last night: I was still getting used to it and it was getting dark. I did only a couple or rolls and figure of eights. I did some pitch pumps and MAN this thing is lightening! I have it setup pretty calm since I still have the 18 tooth pinion on there:

Numbers:
- 2400 - 2500 RPM head speed on the ground (depending on battery)
- 10 degrees collective pitch
- 6 degrees cyclic pitch (roll-flip)

Today: I flew just a bit harder after dialing in the head speed a little more. Flips, rolls, funnels, pitch pumps, stall turns, etc. This thing climbs a lot faster than my 450 does at 3000hs. I am having put in a lot less pitch when rolling or flipping or it climbs a lot. I hate to think what would have happened if I had left the pitch over 12 degrees! I also think I need a little more expo on the tail, but I am getting used to it.

Milliamps per minute: I am using right around 300ma/minute. This means that I should be able to get 5 minutes per battery. I think this will get better once i get the 15t pinion and am able to run higher throttle on the ESC.

If the weather gets better maybe I will get to a bigger field where I can let loose a little more. Maybe some video. Here's hoping.

Tuesday 27 May 2008

More Twitching - Solved?

I test flew again today during lunch. I had a couple of servo twitches and that was enough to make me uncomfortable with anything but hovering a foot off of the ground. It was even misting (sprinkling) just a tiny bit. Strong static to jump on such a humid day. Remember also that I had already sprayed the belt with WD40 which is supposed to kill static*.

When I got home I went out again, but this time before I went out I ran a ground wire from the tail block to the motor mount. I also ran a ground wire from the top main shaft bearing to the motor mount. I wanted to make sure. So I went and hovered the first battery. Nothing. It hovered beautifully. So I let it loose a little on the next battery and flew some Forward Flight, Stall Turns, Funnels, and Rolls. Perfect (well the heli was, I gave too much stick input. This heli is powerful!).

I came home and took off the blades again. Then I unhooked the ground wires from the Protos and spun it up to a low RPM. Then I touched the main shaft ground wire to the motor mount. Nothing. Then I tried the tail boom ground wire. It went crazy. The lipo guard was beeping because of being reset and the servos were twitching. I made a video of it, not that you do not believe me.

I hope this helps some one. I might be the only person with static problems on the Protos right now, but I am sure that I will not be the last.

* I had static problems with my T-Rex 450 SA also, but not this bad (Plastic Blocks and metal boom). Maybe I just have an Electric Personality.

Monday 26 May 2008

Hop - and then problems

I am sorry I have had no other helicopter or field stories to share with all of you. I have not been able to get to the field because of this build and because the weather has been so bad lately here in the Midlands. Most of the time I wish I had never left Southern California, but that is another story.

So, the Protos was finished Saturday night. A friend, let's call him JS, came over with a few parts for the electronics and drank a beer with me while I slaved away. A while after he left it was ready to spin up. So I did. The helicopter spun up nicely and quite quitely for this size of helicopter. The real noise came when it was at it's full 2500 RPM and was beating the air around it into oblivion. Nice.

Then the Helicopter shut down.... I thought it must have been the motor over heating since I was just spinning it up on the ground for about a minute. Strange. I also noticed that the servos were twitching like crazy. I moved the BEC away from the ESC and tried it again. The next time I tried it the same things happened. Random shut downs and servo twitching. I thought maybe I was drawing too many amps fRom the BEC because of stalled servos, so I reamed everything out some more with the ball-link sizer (that comes in the kit). Again it shut down and the servos were twitching like crazy.

I wish I had started taking video or at least pictures at this point... I figured I had tried everything else, and even though I had been told by Corrado at MSH that there was no chance of Static on this helicopter* I should check it out anyway. So, I connected a ground cable to the tail boom and to the motor mount.

Grounding the tail boom made it worse! It actually became so bad that I could have the helicopter on and spin the main blades with my hands and the servos would twitch!. So, I unhooked the ground cable from the motor mount and it stopped doing it when spun by hand. I figured I better test it properly.

I took off the blades and left the ground cable connected to the tail boom but loose. I spun up the helicopter to the lowest throttle point. I then took the ground cable and slowly touched it to the motor mount. I saw sparks and the helicopter went crazy again. I was convinced. This was the worst static I had ever seen. Connecting the ground strap made it worse and so I had one choice... I sprayed the belt with WD40**. Problem solved. I had no more glitches, twitches or shut downs.

Too bad it is not a happy ending though. Before I found the problem my AR6200 remote receiver got cooked. I e-mailed the Corrado and he simply said they never had a problem during testing. Well I am sure that was the same story with the T-Rex 500. I sure hope he remembers what I said when he starts getting more reports.

I hope to fly this helicopter this week and report. Maybe some video at the weekend?


* He actaully said it a few time in teh RCGroups.com design thread, but he said once specifically "I forgot to mention to say goodbye to any static current belt problem, belt obviously touches the metal pinion on the motor so it is grounded the best way possible". My self and others doubted this since rubber is not conductive and actually will transfer charge from what ever it touches to the metal that comes near it, in this case from the plastic pulleys to the metal tail boom.

** Yes, I know WD40 can degrade rubber, but i have used it on my 450 for ages and it never caused a failure.

Sunday 25 May 2008

Spun it up.


Well, the helicopter is just about ready to fly. I got all of the electronics in it yesterday afternoon. The first time I spun it it up the servos were twitching like crazy. I guess that is what I get for mounting the BEC up against the ESC. I should have known better. Spetrum 2.4 GHz does not fix everything. :-) I have moved the BEC and put all the ferrite rings back on and it seems ok now.

The other problem I had was that all the links in the kit need to be opened up with a link sizer (comes with the kit) before fitting. I sized them when putting the kit together, but not enough. The flybar was too stiff and the tail linkages were too much for teh tail servo. I reamed out th links again after seeing the flybar not respond correctly and having the BEC give-up because of of the stalled tail servo. See, the receiver was shutting down. at first I thought it was the motor or ESC, but I thought I would watch teh receiver. Sure enough it was shutting down. Not static, but what? I figured out that it was the tail servo when I picked up the helicopter and turned it the servo tried to do it's thing and 'bam' it shut down again. I think the stalled tail servo was pulling more than 4amps! Anyway, after sizing everything again it all seems good.

Some Tech Junk:

Flybar:When the helicopter is powered down you should be able to push/flick the flybar down and it should bounce back up. If it does not the links are too tight and it will not respond well in flight. Tight links can cause all sorts of issues. I had that issue on one of my first spool-ups and have already scratched my tail blades. :-(

Sticky tail: Some one else mentioned that the tail seemed to act very funny in flight like the servo they had was not enough. Well, my tail was not acting right either. Like I said above, the tail linkages were all too tight and basically was stalling the servo. I just had not reamed them enough. So, pull the front link off the tail servo and slide the linkage by hand. You will know if you need to ream the links more. Don't forget the ones on the tail grips.

Pitch
When setting up zero pitch I thought I would have a look at how much pitch we are getting in the head. Now, I am running 15mm arms and had the default 60% swash mixing.

Collective Pitch available: maxed out my pitch gauge. Must be about 15 degrees. Set mine to just over 10 for now.

Cyclic Pitch available: this was about 10 degrees. I brought mine down to about 6 degrees.

I adjusted both of these with swash mixing in my transmitter. Once I spend more time in the air I will bump these back up and get my 16mm arms.

No missing parts:I actually ended up with extra parts in some bags and did not need to open the spares bag.

Friday 23 May 2008

Coming together.


I have to start with a thanks to the Jesus Bolt blog (great name) for linking to this blog. I guess I am under some pressure now to to put some good content on HeliTalk.

Well, I did not really have any trouble last night while finishing up most of the kit build. I still have to do electronics. There are a few things I did do slightly different than the manual said:

  • I strengthened the tail pully by filling in the gaps outside of the pin area. I wish I had taken a picture. It should not metter though as MSH are sending stonger pulleys out.
  • I put the frame halves together and then slid the servo assembly in. Just like you would if you had to remove the servo assembly after was built. Worked just fine.
  • Mounted my elevator servo on the starboard side of the frame and mounted my rudder servo on the port side of the boom.
  • Bottom of page three said to use thread lock on metal/non metal screws. I did not believe it and only used in on metal/metal screws.
  • I also strengthened the tail fin with carbon rod and epoxy. Much stiffer. We will see if it survives a messy auto...
It seems a few of the kits have been missing parts. I guess I got lucky because mine had everything I needed. The teething problems with this new company and heli seem huge, but lets hope with some communication and some good customer service this company survives and pushes this cutting-edge heli into the mainstream.

I think it is looking pretty good. I need to pick up some bullet connectors for the motor ESC (why would an ESC just come with the female half?) and I think that will be it. I am using 15mm plastic servo horns for now, but I have some 16mm aluminum ones on their way.

Maybe some video this weekend? Well, maybe if the weather holds out.

Wednesday 21 May 2008

Protos Arrives


Just picked up my Protos. I seem to be the first to purchase and receive my Protos outside of Italy. :cool:

There was a problem with the pinions shipment and my dealer did not receive the 15t or any other spare pinions. Some dealers may receive them though. I Should receive the 15t next week. I checked and the spare parts bag is in the box. They have the rest of the spares though.

I did not let on in the forums, but I know at least some people that were on pre-order lists that will not get their Protos from the same shipment I did. Seems the rest of the helis are being shipped later. We will see.