How to zero out pitch/roll/yaw rates at center sticks for the bad mainboards

[bmc76]

Thanks for the tip, I just added about 2L to the aileron, everything else was good. The left servo likes to jitter up and down, maybe need to adjust gyro gains?

[DoubleCH]

You're welcome. Most usual suspect of linear servo jitter is dirty carbon/metal strips. Do a search of servo cleaning DeoxIt on this forum section.

[helihaven]

DCH, I just wanna thank you like all the rest! I never would have done this on my own, hell never woulda caught it in fact. Thanks for the info...was just following the instructions saying no trim or subtrim...and this thing was driving me nuts...I knew i had it perfect mechanically, yet it was all over the place...I was constantly correcting for the drift I didnt even know was there!

I might add here that i'm only using the board itself...not the rest of the 130x. It is installed in a trex 250, and the board runs a spin 8800 kv motor with 15:1 reduction, 3 DSP-60J spektrum 6 gram servos on the swash, with a DS76T eflite servo on the tail. That little board doesnt even get warm nor the motor..wasn't expecting it to turn out this well in fact.

When I zero out the board as you instructed..then disconnect and reconnect the battery, it goes right back to drifting....I go through the whole process all over, but in the end, I wind up with the exact same trim numbers as I started out with..sooooo I will just leave it there...and the first 3-4 minutes of each flight I will hover until it stabilizes I guess? (no biggie as i get 15+ minute flights at over 4000 HS hehee)

[sbarro]

Originally Posted by helihaven

DCH, I just wanna thank you like all the rest! I never would have done this on my own, hell never woulda caught it in fact. Thanks for the info...was just following the instructions saying no trim or subtrim...and this thing was driving me nuts...I knew i had it perfect mechanically, yet it was all over the place...I was constantly correcting for the drift I didnt even know was there!

I might add here that i'm only using the board itself...not the rest of the 130x. It is installed in a trex 250, and the board runs a spin 8800 kv motor with 15:1 reduction, 3 DSP-60J spektrum 6 gram servos on the swash, with a DS76T eflite servo on the tail. That little board doesnt even get warm nor the motor..wasn't expecting it to turn out this well in fact.

When I zero out the board as you instructed..then disconnect and reconnect the battery, it goes right back to drifting....I go through the whole process all over, but in the end, I wind up with the exact same trim numbers as I started out with..sooooo I will just leave it there...and the first 3-4 minutes of each flight I will hover until it stabilizes I guess? (no biggie as i get 15+ minute flights at over 4000 HS hehee)

Ingenious, I never would have imagined that the 130X board could handle all that extra power.
That tail design looks really cool as well

[atv223]

I didn't realize I had a problem until I read this thread. I just thought it was normal to have to put tons of cyclic and rudder in on take off (my only other CP heli before this was an mCPX, and although that didn't have this issue, I just thought it was the design)

When I did the bench test, my servos really drifted badly very quickly. After messing around for quite a while, I got it pretty stable and level. However, when I went to try a take off, it was like I hadn't done anything or just moved the problem around. So tried it "live" or dynamic. I would spool up and if it pitched right, I would give it some left sub trim, etc, etc. To my amazement I was actually able to get the heli to spool up and lift off nice and even with only collective input.

The thing I am struggling with, is that it doesn't seem very consistent, from flight to flight. The rudder stayed constant, the elevator maybe a click different, but the aileron maybe needed a change of 3 or 5. Any thoughts on this?

I can see how much better this heli flies once this is straightened out, I am not constantly fighting to keep in in a hover. One time I got it in nearly a hands off hover for a bit.

Any further suggestion would be greatly appreciated.

[edjo69]

My subtrims do not remain exact from battery to battery, but they are very close, close enough to just use a click or two of regular trim during flight.

[DoubleCH]

I set my subtrims with a fresh battery and never touch it again. Subtrim requirement may shift towards end of charge (heard some mCPx boards do that, too) but for my 130X board it's consistent from fresh battery to fresh battery. And 99% of the time I take off with fresh battery until end of charge so I don't really care much about subtrim requirement at any battery status except fresh charge.

[phwm]

The sub-trim required for aileron can drift between -5 to -9 for my mew board. At one time I had to go down to -20.

At the end I put back my old board which requires totally no trimming except a -20 for pitch.

The QC is not there at all.

[steveap1]

Anyone have this problem develop after having flown the helicopter a while? That seems to have happened to me...when I first installed the board I did not have a problem.

[litehawkdown]

Originally Posted by edjo69

My subtrims do not remain exact from battery to battery, but they are very close, close enough to just use a click or two of regular trim during flight.

Check the calibration of your TX.

[JayH]

Originally Posted by JayH

I remember back years ago, this was a common problem with the old CSM gyros, the 360 suffered heavily from this. Always had to add subtrim, the CSM 540 was a bit better. always had to add subtrim. Dont know exactly what function of the gyro sensor the millisecond pulse is changing with a subtrim change. But good find none the less.. Im gonna go check mine real quick.. Ill report back.. Im about 30 flights on mine.. I dont hover long enough to see if it drifts, but it is slower rolling to the left than to the right. but in a inverted blade scrape it always seems to drift right on the ground. We will see what happens..

So, I just tried this. I have absolutely no drift on my board. all subtrims are at "0" I let it sit there for about 5 min. I pretty much mimicked your video step by step. Guess im lucky for now. next i will try to find out why the roll rate is less to the left.
BTW. my setup is basically stock with exceptions of the tail pitch slider, 2 holders for the tail rod and the metal tail blade holders..

Just an update, now sitting about 20 more flights since last post. I started to notice my swash drifiting to the left. So had to add +3 clicks of sub trim to get it to level out and not drift.

[rcgood]

I have the problem where I hook up the battery and the board binds (blue led turns solid). But as soon as I move the right stick it starts blinking 3 short pulses at a time. I can't throttle up anymore but still have some cyclic control. I re-binded a few times and I tried different batteries. Will the method described here fix this problem?

[DoubleCH]

No, sounds like you plug in battery with non-zero throttle. This will enter gyro gain programming mode and have the symptom you mentioned. Do you hear ESC beep a few times on battery plug-in and then after a few seconds a few more beeps?

[rcgood]

Originally Posted by DoubleCH

No, sounds like you plug in battery with non-zero throttle. This will enter gyro gain programming mode and have the symptom you mentioned. Do you hear ESC beep a few times on battery plug-in and then after a few seconds a few more beeps?

That's not the case. I do have zero throttle and it binds.

[ignited]

CH,

My swash exhibits the same same exact behavior as yours during spool up (specifically, the entire swash dips right and I'm forced to counter the movements and correct it with holding aileron left).

Should I just go ahead and make the mentioned rudder subtrim adjustments as well? Or wait for the problem to occur?

I have caught myself in the past replacing C-gears that never looked stripped but I thought it was because of my poor eyesight.

To sum it up, if you were to pick up another 130x tomorrow would you make these subtrim adjustments prior to taking the heli off the ground?

[DoubleCH]

If I get a new 130X I'll definitely check subtrim before doing anything else. In fact, that's the 1st thing I did after binding my friend's at the LHS before he bought it. Not sure what you mean by waiting for the problem to occur. If the board is bad and needs subtrims, it'll need subtrim from day 1 and remains the same subtrim requirement for the rest of its life.

[johnthekeymonkey]

I ordered a new mainboard hoping that HH has already fixed this problem for their spares. If not, I will send the new unit back and HH will fix it. During the 4 week waiting for the fixed board I can fly my buggy bird with sub trim as usual.

[helihaven]

The replacement board I bought to use in my hybrid 130x/250 project drifted on all 3 axis'....so I would say as it is only 6 weeks old, the replacement boards sometimes have the issue as well....

[johnthekeymonkey]

Ack.
My delivered board also has a faulty roll axis sensor. It will be sent back to the hobby store and then to HH for repair.

[Ric66]

Reminds me of the quirky "swash leveling on rudder input" flaw that all mSRX's have. HH has never acknowledged publicly that there is a design flaw in the control algorithm (as far as I know). mSRX owners continue to hope with every new board version that a factory fix will emerge. This 130X problem may be a manufacturing QC issue, but it appears to be so common I would not consider it a defect in just a few boards. Perhaps the slight variability of resistance or capacitance values in controller board components is causing the issue, and there is no built-in feature that allows adjustment during factory bench testing (calibration). I think the HH approach is typically to replace boards for those who complain the loudest and hope the next one shipped will either fix the problem by chance, provide a placebo affect, or cause the consumer to just give up or find a workaround. Don't get me wrong, I think Blade helis are amazing marvels of micro-engineering, I just wish their tech support would come clean and help us to know exactly what issues we are dealing with. However, I am realistic enough to understand the business and litigation concerns they have. That said, thanks to DCH for helping us find and implement this awesome workaround!