Is this normal? hit TH and nano spins on ground

[neuroticindian]

Put a new nano HH BL motor in, everything is completely normal on it, except when I land it and hit TH, it starts spinning.

Here's a video, I'm controlling with one hand and filming with another. I have put it in idle up mode and then hit TH, I was controlling the rudder a bit in the beginning, but the spinning at the end is only due to hitting the TH and nothing else. I'm not sure whether this is normal, or I might have done something wrong.

Video

[Dutchdrifting]

Do you mean the turn at the end? Thats normal. Either the tail or the main stopped spinning causing tailblowout until all have stopped.

[neuroticindian]

Yeah, at the end, forgot to write that, just changed it.

As long as its normal, I'm happy, lol.

[Dutchdrifting]

My wild mcpx turn about 4 complete circles on th in iu. The tail motor stops almost instantly while the main takes its time. Nothing to worry about.

[gerdawg]

Yes, it's completely normal. It's like a throttle brake on the motor.

[neuroticindian]

Perfect, I figured since the BL is running much faster than the tail, it probably takes a while for it to come to a complete stop.

Thank you all.

[sethf8403]

brushless motors just stop, they don't free spin like the stock motor, so the rotorhead grabs the heli frame and takes it for a ride before they both slowdown, simple phisics...picture two skydivers, one is spinning like crazy a few feet above the other guy who is not spinning at all, then the spinning guy suddenly bearhugs the guy who isn't spinning, what happens? suddenly they are both spinning now at about half the speed of the original first dude...

a similar thing is happening here only the rotorhead weighs a lot less than the heli so picture a spinning midget grabbing an average dude and it's probably a little closer to reality...

in a stock setup the midget never grabs the other dude...

[JEBSi]

Try some micro bearing oil on all of the bearings. These helis can't get enough of the stuff or it will start to run rough and bind a little like what you have going on in the video. I have had a bottle of this niftech micro bearing oil for over a year now and only used 1/4 of the bottle and I use it just about everyday multiple times. It has a needle applicator tip which is perfect for squeezing into these micro bearings and it stops waste.

[splatt860]

Mine does the same!! I think it was due to the rotor stopping abruptly and that it being a bl motor.. my brushed motor all lubed up is super smooth, the bl motor has dead spots most likely not the correct term. Like when the second hand on a clock turns. . . . . .

Sent From My Dx7 Flying My Brushless MCPX

[sethf8403]

These helis can't get enough of the stuff or it will start to run rough and bind a little like what you have going on in the video

im inclined to disagree, a tiny amount is needed, any more than that and it gets sprayed all over the heli, attracting grit and dust, causing excessive wear and wrecking main gears...

[JEBSi]

Originally Posted by sethf8403

im inclined to disagree, a tiny amount is needed, any more than that and it gets sprayed all over the heli, attracting grit and dust, causing excessive wear and wrecking main gears...

A tiny amount in all of the bearings often, and yeah it can get messy, but it runs smoother than not doing it. I use a toothbrush to clean the heli just as often as I oil it along with rubbing alcohol and a paper towel to wipe the toothbrush clean. No real excessive wear on main gears, but it will attract dirt if you do not get extra oil cleaned off of areas that it should not be on. Main gear teeth get black no matter if you use oil or not. I put it everywhere as in every joint that moves on the head and mainshaft bearings to cut down on any friction. If not the battery can get hot and wear out quicker, if it has to push through extra friction. Plus the heli can start spinning like in the video even with a non bl setup if anything is binding between the mainshaft and frame. The swash gets dry.

[neuroticindian]

Good discussion here, learning quite a few things. Just wanted to pop in and say that I had only flown the nano outside on grass once before putting the BL in. The problem doesn't exist when I switch to the stock motor, only with the BL upgrade.

This is what leads me to believe its the BL upgrade causing it rather than binding or anything of that sort.

Getting some good info on how to clean the servos though!

[ahahn]

It was pointed out by Dylan, some time ago, that for some reason, the HH BL ESC applies a brake when the throttle goes to zero.

This is just a simple screwup I think. It would be nice to be able to turn the brake off. A spinning tail is exposing one of the weakest links on the nano to whacking something, I think I could deal with spinning main blades. Well that's my opinion anyway!

[TTMR]

Originally Posted by splatt860

Mine does the same!! I think it was due to the rotor stopping abruptly and that it being a bl motor.. my brushed motor all lubed up is super smooth, the bl motor has dead spots most likely not the correct term. Like when the second hand on a clock turns. . . . . .

Sent From My Dx7 Flying My Brushless MCPX

Yep, the dead spots are magnetic and just a fact of life

[Iskareot]

Yeah this happens to them all from what I have seen./


But thats ok because damn this thing can now do flips like no tomorrow -

[ninja1900]

The only time I've seen this happen is when my TX is low on battery.

[bmc76]

I just lower the collective as soon as I hit TH, stops the spinning before it tips over.