Bad vibration on my T-Rex 450

Recently, I noticed a bad vibration at slow headspeed on my T-Rex 450. I can even see it wobble a little while looking at the main button. This is weird because I didnt crash or anything.


Someone told me I should suspect the main rotor housing, so took the whole head apart, leaving only the swash and the main shaft on and I gave it a try. I watched the main shaft closely while it was rotating at low speed and I couldn't notice any wobble nor vibration at all.

From this point, I started by installing only the main rotor metal housing, I screwed it to the shaft directly without the seesaw or anything else and I redid the test. This time I could easily see the housing wobbling at low rotating speed!

From this experience, it seems clear to me that my housing is a little bent or something, because it wobbles with only this piece on. It's weird, because I didnt crash at all, maybe I bent it while working on the heli or transporting it.. anyway, I'm gonna replace it and see if the vibration goes away.

I will post the results when I receive the new housing...

In the meantime, here is my main suspect:

First flight of the season

Today the weather was wonderful outside and I decided it was time to take my TRex-450 out for my first flights of the season.

There is still plenty of snow all over the place up here in Canada at this time of the year, but it's melting pretty fast these days and it's beginning to be hot enough to be able to stay outside bare-handed for a while without freezing!

It was about +12 celcius this afternoon and it was quite comfortable. The local neighborhood park where I normally fly my 450 was still covered with about 3-4 feet of snow, but I placed the heli in the street behind my car for takeoff and I flew over the snow while standing in the street :)

I flew my 2 packs and everything went very well. I was a little rusted after not flying (except for mCX and simulator) for a few months, but after a few minutes, I was back doing some mild 3D loops and flips.

Like often when I fly at this park, a few kids stopped by and watched me flying.

So my flying season is now officially opened!

Cordless nitro heli starter

In preparation to my future nitro helicopter, I was looking at my old plane starter and I decided to mod it a little to use an old Align 3s 11.1v lipo pack that I don't use anymore on my T-Rex 450, because its a little puffy and it wasn't lasting really long.


After reading several posts on this subject from people saying that a 3S lipo pack had enough power to start a 50 nitro heli engine, I simply cut the wire of my old plane starter and soldered a dean plug to it at about 2 inches and I used my dremel to remove some plastic on the bottom of the starter to make some room for the lipo pack that I strap to the starter using some velro bands. I also soldered the other part of the dean plug to the old starter wire, so I can still plug it to my field 12v battery if needed.

It looks pretty cool in my opinion and I tried it on my old .75 SuperTiger plane engine and it works very good. Since I dont have a nitro heli yet, I can't be absolutly sure it will work ok, but I really dont see why it wouldn't work.

Anyway, it was a really easy mod to do and it didn't cost me anything because I had all the required parts laying around.

Here is what it looks like:

Which gyro?

As I'm still trying to fix my mind on all the parts for my next Trex 600NSP, I'm having quite a dilemma right now about which gyro to choose. At one point, I was all about the Futaba GY611, but then I started to read more and more stuff saying that even if it's still a pretty decent gyro, the 611 is not the latest generation anymore.


Apparently the Spartan is the one to have these days. Of course, there is also a lot of other possibilities out there, including the Solid G and the JR770 so it's really hard to decide since they all seem good and they are all in the same price range from what I read.

Yesterday, I came across the new Futabe GY520 http://www.futaba-rc.com/radioaccys/futm0807.html
that is due to be released any day now. This one really got my attention, since Futaba is a well established company and they alreay own a great share of the gyro market. From what I understand, this is gonna be the next killer gyro, but I'm wondering if it is safe to buy it as soon as it gets released. I will probably order my stuff pretty soon, so I'll be monitoring the release of this gyro in the next weeks...

decision.. decision!!

Recycling an old PC power supply

In the October 2008 issue of RC Heli magazine, there was a great article about modding an old ATX PC power supply into a multi purpose 12v power supply.

Since I read this article, I wanted to give it a try and in the last days, I finally had some spare time to do it. I followed the article carefully and a few hours later, I have this great 10amps 12v power supply:

It was a really easy mod. All I had to do was cut some wires inside the power supply and solder some leds, a swicth and banana plugs. I decided to do it the fancy way using leds and stuff because I already had all of that in my toolbox, but some could do this same mod without all the bling and still get a nice cheap power supply.

PC power supplies are often rated at least 10A and many of the recent ones are even rated at 15-20A. So if you have one laying around or if you know someone who is getting rid of an old computer, chances are you can get yourself a great 12v power supply for almost nothing!

The ironic thing is that I don't even need a 12v power supply for my RC stuff, because I only use the Align lipo charger/balancer that came with my T-Rex 450 and is already has a 110V cord, but it could always be useful and I couldn't resist doing this mod :)

Almost there...

Today I've been resisting the temptation to get my TRex 450 out and fly for the first time of the year. The temperature is starting to warm up a little and it was aroung +5 celcius outside, so the idea of flying my TRex 450 went through my head, but I resisted and I think it was the right choice, because it was a bit windy and even if it's warming up, it's still a little cold. I really dont like getting my fingers cold while I'm flying, because it makes my reflexes weaker and I'm more prone to crashing.

2in1 or not?

These days, I am reading as much as I can on the internet concerning the Align TRex 600 NSP and my mind is now almost set on what I will buy, but there is this 2in1 thing that just keeps bugging me. The 2in1 unit that comes with the NSP kit seems awesome. I really like the glow starter button, but the more I read about this unit, the more I read bad things about it.


The Align 2in1 unit doesn't seem to be a very reliable piece of electronic. Apparently, the on/off switch easily gets corroded and a lot of people are reporting crashes dus to this unit. On the opposite, many people also say its working fine for them, so I'm a bit confused here.

From what I read, the replacement of choice for this unit is a Fromeco Arizona regulator paired with a SwitchGlo. This way, you get the same functionnality and some piece of mind, but there is a cost to it, which is approximatly 200$ CAD more, so right now, I don't know yet what I'll do.

The only thing that is sure is that I will get the 2in1 anyway, since it comes with the NSP kit, but will I use it or just sell it on ebay? Not decided yet...