MambaMax ESC quirk - Page 2 - RC-Monster Forums

BrianG · 11.14.2006, 12:58 PM

I don't have the problem when taking off from a standstill, it's only when I used the brake to come to complete stop (no motor movement at all) and then try to go forward again. And even then, it only happens sometimes. I have been able to come up with a specific action where it is perfectly reproducable.

Since I'm using the MM in a small, lightweight truck, it recovers fairly well. However, using it in a relatively heavy buggy or MT exacerbates the problem since the ESC will have a harder time to get the truck to move due to load and motor size.

Personally, I think it's just a matter of the motor position sensing algorithm. If CC could recreate it, I have confidence that they could release an update to solve it.

Believe me, I'm all about sensorless designs, but it's issues like this that give sensorless a bad name. It has to be something specific to the MM, because my Quark doesn't do this at all (I tried it).

Serum · 11.14.2006, 12:58 PM

Glass;

What setting on forward/reverse do you use? forward only? i find the forward/reverse setting a horror.. It blocks the wheels entirely.

glassdoctor · 11.14.2006, 12:59 PM

Just to make it clear... I get zero cogging in 1/10... and I have not noticed the "racing glitch" with the 1/8 stuff...

glassdoctor · 11.14.2006, 01:03 PM

forward only... or reverse lockout...(happens with both) I have never run the forward/reverse setting...

I run a M8/Spektrum and my buggy runs a KO Helios/Spektrum

I have tried a lot of different esc settings but nothing "fixed" it... I think Castle needs to look at the software to build in something that makes this glitch impossible. I have not seen it on other controllers....

Serum · 11.14.2006, 01:06 PM

This is the first software release on the mamba-maxx. I remember the mamba 25 cogging like crazy in the beginning with the higher KV motors. A software update fixed this problem. However, my 8K and the mamba 25, misfired from time to time.. All of a sudden you heard this funky squeak coming from the motor, without moving the vehicle like it supposed to do.. after the software update i didn't had the issue anymore.

glassdoctor · 11.14.2006, 01:24 PM

When we first talked to them about this they were wanting to replicate it so they could fix it in software... but now it seems they are using the connector as a scapegoat and don't act interested in pursuing a fix other than to say cut off the connectors.

I think they can and will fix it, but they seem to say it's just us and they don't see a problem. Which has me a little disappointed in them right now.

I have some more testing to do... and I will likely visit them at their shop sometime soon when I think I can put the car down and show them so they can see it with their own eyes.

Serum · 11.14.2006, 01:27 PM

glass; did you called them?

if a direct soldering doesn't work, you've got another reason to contact them?

seems to me like they where only trying to make a suggestion on a for them unknown problem.

BrianG · 11.14.2006, 01:37 PM

Hmm, so it's not specifically related to using reverse then. Well, at least that's one possible cause we can eliminate.

I would highly doubt it's the connectors. Even when the wires are warm after an hour or so of constant use, the connectors are still relatively cool, so I know there is good contact there. And the actual motor wires are MUCH shorter than they were when new - only about 2.5"-3" total from ESC to the motor now.

I really hope it can be fixed with an update.

Quote:

Originally Posted by glassdoctor

I have some more testing to do... and I will likely visit them at their shop sometime soon when I think I can put the car down and show them so they can see it with their own eyes.

Does CC have a local office or something?

glassdoctor · 11.14.2006, 01:56 PM

It's not that the connectors can't handle the load... it's that they think possibly the micro pulses used to "see" the motor doesn't like the connectors being there.

serum... yes both myself and another local racer have talked to them quite a bit about it. It sounded pretty good for a while that they really wanted info and wanted to nail the issue... they were not happy to hear there was such an unkonw bug in the system still.

But once they recalled the guy who said he stopped his problems by direct soldering, it seems they called off the dogs and are content to just blame the connectors and say that they can't replicate the glitch so it's just me and my buddy that has a problem.

The guy who reported the direct solder fix is the 160mph speed run guy (nick?).... the funny thing is that he wasn't even running mambas in his cars.

I haven't called to ask Castle if they know exactly what setup he was running when he "fixed" his glitch. But his speed cars ran the airplane controller and a neu motor.

I have talked to several guys at CC and I will continue to... but the past few weeks I'm kinda taking a break, and haven't done much with r/c except for one weeknight race...

I plan to mess with stuff and see if I can make it do it a lot... so I can go to Castle and show them exactly what it's doing in person.

This isn't over by any means. :)

glassdoctor · 02:07 PM

Castle is in the Kansas City area.... I have relatives in the area so I get down there once in a while.

edit for spelling :)

11.14.2006, 02:22 PM

they are usually really good with customer support... who did you talk to? ask for Joe Ford... i've dealt with him in person before an he's very helpful...

captain harlock · 03:26 PM

Nick Case was the one who made the 160mph speed run and he was using the CC Phoenix HV-85 controller as far as I know.

Serum · 11.14.2006, 03:52 PM

Brian, glass; what motors are you guys using? I thought you are using a Neu, Brian?

Glass, what motor was on the racer? was that the original mamba motor?

BrianG · 11.14.2006, 05:33 PM

I'm using the bundled 4600 motor on 2s2p. I tried lowering the gearing too and that didn't help (or if it did, it was not noticeable).

glassdoctor · 11.14.2006, 06:07 PM

I have talked to Joe, Shawn, and Bernie. All have been good guys to talk to.

We are racing 1/10 offroad with the stock MambaMax systems, motor and esc.

My cars:
B4 with 4600
T4 with 5700
XX4 with 7700

Other guy:
B4/XXXcr with 5700
T4 with 5700

Yep... Nick was running the HV and a Neu 1509 on kokam lipos I believe.

I'm not coming down on CC for this... I'm trying to help them figure out what's going on with the system. I don't think it's just ours that are doing it. It's a subtle problem especially for those not racing. And no offense, but also maybe not so noticeable to those who are not very good drivers. :) And like I said before... on a rough track, in grass,... this would be hard to detect.

And there's a lot we don't know...