microviper 10 esc stutter forward only

[H2Ohaze]

For practical purposes, both motors should see the same juice; but if extra resistance gets in there with a carbonized brush or one has a bad winding...things can be different. At least I think.

I had a monster truck RC with a 775 brushed motor. It got in the mud a lot, and I'd turn a tap on and put the motor vents right underneath...blow out with an air gun then a drop of oil. One happy powerplant.

But I don't see where to do that on these little guys...?

[He Who Shall Not Be Named]

Those motors may not have the vents -- our vendor's sell motors to our specifications, but not all motor cans or back-plates are the same. Some are vented, some are not. No sure-fire way of getting the water out once we scrub the brushes with the H2O treatment. Damn. The ESC is waterproof, but not the servos.

David

[H2Ohaze]

Yeah, I thought I knew what vents on motors looked like, not only from that huge 775, but plenty of small motors I've come across. I went through about 5 or 6 pump motors while redoing the Holland to get the right one. But no opening on these things- unless it's hiding.

I had a thought of drilling a hole or two in the can but I'm about sure that is a terrible thing to do, those cans are magnetic. Magnetic filings would then be all over- not good for health of motors.

Yikes David, what now? I don't think I want to try and figure out how to R&R a motor on this thing. Everything's crammed in there.

[He Who Shall Not Be Named]

Yeah, I thought I knew what vents on motors looked like, not only from that huge 775, but plenty of small motors I've come across. I went through about 5 or 6 pump motors while redoing the Holland to get the right one. But no opening on these things- unless it's hiding.

I had a thought of drilling a hole or two in the can but I'm about sure that is a terrible thing to do, those cans are magnetic. Magnetic filings would then be all over- not good for health of motors.

Yikes David, what now? I don't think I want to try and figure out how to R&R a motor on this thing. Everything's crammed in there.

You've suffered enough. Package up the motor buklhead (with attached devices) and send it to me for repair.

David Merriman
835 Holly Hedge Ave.
Virginia Beach, VA 23452

[H2Ohaze]

Thanks, David. It sure has been an Odyssey. I'm going to include the SL-8, ADF2, Lipo Guard, LPB, power plug, wires routed as I had them all though this. I also have labels on all my plugs, so you won't go crazy trying to figure out what is going where. Maybe you can figure out the gremlin.

Your demonstrated care and thoroughness will make work on my end easier, I'm sure.

David

[H2Ohaze]

Sent out, you should get it UPS ground next Friday.

[He Who Shall Not Be Named]

Standing by

[H2Ohaze]

Did you get it yet?

[He Who Shall Not Be Named]

Got it last Friday. Awaiting EOD. It's been soaking in water till they get here.

Joking aside, I'll take a peek at it tonight -- right now I'm trying to get a custom GATO SD put together.

David

[He Who Shall Not Be Named]

Nice job with the packaging, Jim. No damage. And a big pat on the back for the clean, well thought out assembly of the devices and packaging of the leads. Good stuff. Love how you've tagged each lead plug with port and function. Very anal-retentive, and makes my trouble-shooting job a lot easier -- we all can take a page from Jim's book here, gang!

First thing I did was to yank all the plugs from the receiver but for ch-1 so I could program the SL-8 receiver to read my transmitter, which is on 69. Receiver works fine. Pushed all the plugs back into the receiver and powered up. Throttle had big hick-up issues. Pulled all plugs and started in on the trouble-shooting routine: one device to the receiver at a time and check each device for proper function.

It was getting late so I got as far as checking the ESC. And Bang! from the start I got the stuttering at high-throttle. First thing tomorrow I replace the ESC and see it that's the issue here.

You'll note use of my power-supply rig during the initial evaluation run.

[H2Ohaze]

Thank you. I was surprised when I ran the Rx channel 3 (esc/BEC) through my servo tester and the motors still stuttered forwards. This of course, takes the Rx out of the equation, the motor stutter is not due to Rx interference. And it does seem as if the starboard motor is weaker. Gremlins...

[He Who Shall Not Be Named]

Following a conservative testing methodology I too took the receiver out of the loop and found, as you did that the ballast system servo stuttered. I then replaced the ESC with no change. I've added a third capacitor to each propulsion motor, no change. I broke out my type-7 SD and it works fine.

Oh! Deary me! Bother!

I'll address this problem again Monday -- got production work to get out of the way this weekend.

[H2Ohaze]

Thanks for the update. And your help. Seems like trouble in River City.

Well, all I can think of is bad motor(s), bad ADF2, or bad mojo. That starboard motor is acting funny wrt torque.

Is it possible that a wire is catching EMF/RF, or the motor can(s) is not grounded w/ capacitors to the sheet metal? I don't know...

[He Who Shall Not Be Named]

Thanks for the update. And your help. Seems like trouble in River City.

Well, all I can think of is bad motor(s), bad ADF2, or bad mojo. That starboard motor is acting funny wrt torque.

Is it possible that a wire is catching EMF/RF, or the motor can(s) is not grounded w/ capacitors to the sheet metal? I don't know...

Your last observation is a good one. I'll swap out the entire device tray to a new motor-bulkhead with fresh motors. If that solves the stutter problem, I'll back-track through the entire motor-bulkhead assembly and find the bad-guy.

Good thinking, pal!

I can now put down this three-pound sledge-hammer.


David

[H2Ohaze]

Is there any variation in motor supply? In the stock bin, does one motor look different from another? Are they coming from more than one vendor? Was there a recent change from any one given vendor?

The big question would then be: does one motor perform differently from another, i.e torque, motor stutter forward, EMF when plugged into the SD causing servo chatter with ADF2, etc.

If not that, then tying the capacitors to the can/metal would be the other variable.