450 Trex 450 Pro Motor Timming?

Rob Lancaster

Active Member
Hi guys; the build goes well!
I managed to pack all the electronics on to the airframe. Except the LED nav lights, I'll install the system after I tune in the heli. I got a nice spot saved for the controller.

Ok, here's the questions I promised..

I had to use the motor that came in the kit because the Scorpion motor I wanted to use is to wide for the airframe.. The manual says to set the timing to med. My ESC has a range from 0 to 30 degs.
Am I to assume, a medium setting is the same as 15 degs?

How does the one way bearing work? This has had me mystified for years...

All that's left now is to reprogram the gyro's end points and such. Double check the servo centering. Level the swash plate. And dial in the head... I'll also use some black silicone rubber to prevent chaffing of the wires that go through the frame.

Oh I almost forgot, the rudder servo's ball link seems to be in slight contact with the tail booms mounting block. I can't even slide a piece of paper between the two so I need to make it right.

And should the motor be so hard to turn? Seems the magnets are so strong...

Lions, tigers and bears; oh my...………….. LOL!
 
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Tony

Staff member
Starting at 15º on your timing is a good start. Fly it for two minutes and bring it down and feel the motor. If it's cold, you can advance the timing. If it's hot, then you need to retard the timing. And if it's cold, but has plenty of power for you, just leave it alone.

OWB, it is a sprag clutch. One way the rollers slide up into the body and allow the shaft to spin freely. The other way, the rollers are forced down onto the shaft locking the OWB and the shaft together. This is usually done with an angled slot for the roller bearings on the cheap ones. If you open up an automatic transmission in a car, the sprags are forced down via a spring.

I couldn't find a gif of the type we use, but just imagine there is no spring and not as much clearance behind the roller. The casing that the roller bearing fits in in the bearings we use is way tighter than this gif so it forces the rollers out.

Sand the edges of the frame with 600 grit wet. No need to use silicone then.

Strong magnets in a motor causing heavy cogging is a good thing.

WindingWigglyAtlanticblackgoby-size_restricted.gif
 

Rob Lancaster

Active Member
I hope you're having a good morning my man....

Gotcha on all counts... And yeah the graphics you sent instantly solved another head scratcher... Nice!!

600 grit -A-,,, sounds good, thanks buddy!
 

Tony

Staff member
Having a sore morning. Threw out my left shoulder doing exhaust work on my wifes car. 2 man job and I was the only one around. Getting too old to "just do it my self" lmao.
 

Rob Lancaster

Active Member
Oh I know what you mean,, I wish I had a rack and I was younger and stronger.. I want to keep jamming but my shotty body keeps holding me back..
But we shall keep on to the end. Thank goodness for cool hobbies!
Rster...
 

Rob Lancaster

Active Member
Well I don't know how I did it but I screwed up again..
Some how I plugged in the aileron and pitch servos in reverse. And some how one of them need to be reversed with the TX.

After going through a mynah birds nest of wires, I got it sorted out.
Next up I had a problem with the gyro's compensation. I always moved the rudder stick to the left to set it. But after three times, the compensation remain reversed. So I had a brain storm, I'd move the stick to the right next time, and bingo! It's compensating properly now.

Why did I have to move the stick to the right this time?
The gyro is still facing up like on the last heli. However it's wires are running down the right side of the frame, not the left like on the old heli.. Could that cause that to happen?
 

Rob Lancaster

Active Member
Using the Spartan Quark and I'm using the same servo from the old heli. Same equipment, that's why I was tripping out...
 

Tony

Staff member
So we are working on a flybar helicopter? It's very late for me and I'm quite tired so my CRS is really kicking my butt lol. If you didn't change the servo, or reverse the tail gyro, then I don't know what could have caused it. Unless you put teh tail blades on backwards which is pretty easy to do.
 

Rob Lancaster

Active Member
LOL, nope I did the tail rotor back wards thing all ready... :biglaugh:
I got the Trex 450 Pro FB...…
Get some sleep buddy, no rush...
 

Tony

Staff member
I will go to sleep when the wife heads off to work. Still working on that friggin server.

On your helicopter, if it's working, run with it. Do what I can't, get outside and fly it lol.
 

Rob Lancaster

Active Member
Ok I just finished, at least for tonight, dialing in the head.
First off, this thing has WAY LESS slop in the mechanics than the HK450GT clone. So it was pretty easy to get to theses numbers.

Blue marked blade: 14.8 Neg.
.5 Center
14.5 Pos.

Silver marked blade: 14.9 Neg.
.5 Center
14.4 Pos.
What do you think? Should I bring the swash down one turn? Just for fun...…….. :banana:
 

Rob Lancaster

Active Member
I finally had enough backbone to reset the GOV today. But that's it.....
The only issue I had was when she was spooling up, the tail went more than 360 degs before it stopped.

Can I trust the Gov calibration, while the tail is moving that much?
And also, what do I adjust to keep the tail still while spooling up?
Almost there!
 

Tony

Staff member
If you don't have slow spool up turned on, it is going to whip the tail around from torque. The tail blades do not have enough authority to stop it. As long as the tail stops when the head is spooled all the way up, it should be fine. Not sure though since I can't see it and I"m not there.
 
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