My E-Revo questions and build - Page 3 - RC-Monster Forums

j-man · 05.02.2007, 02:53 PM

Yep, just when it's barely moving.

BrianG · 05.02.2007, 06:02 PM

Is the ESC that is squaealing, or the motor? The motor is what is supposed to make the beeps and digital music :).

jnev · 05.02.2007, 06:42 PM

BrianG - you mean the ESC is supposed to make the beeps and digital music.

Looks really good. Tell us how it works for you out in the open, will you? Have fun with it.

nieles · 05.02.2007, 07:16 PM

Quote:

Originally Posted by ***RC***

BrianG - you mean the ESC is supposed to make the beeps and digital music.

Looks really good. Tell us how it works for you out in the open, will you? Have fun with it.

no he means the motor.

the controller sends short pulses to the motor and then you hear the beep

you can hear it is the motor because every motor has a other sound, the lmt motors have the coolest beep. if you have a few other motors you should try it and hear the difference

j-man · 05.02.2007, 11:28 PM

Man is it sweat! No gogging, works great. It's so smooth I can even drive slower than with my long gone stock e-maxx.

There is the light show and beeps and digital music when turned on, and just as it's barely moving an sqeel kinda sound. Dont yet know if it's the motor or esc.

I got roughly 16-20 minutes of run with 12 cells IB4200SHV, and it was -3*C weather. Half WOT, half anything from crawling to mid speed.

After from what I could understant (I was freezing), ESC was very cool, but motor got a bit warm/hot. I gues it's a bit under geared?
I still need to weight it to see how heavy it is.
And get an good slipper before making any big jumps, running some diff balls in the spur now and hence not much slip:027:

If I didnt mention it has got 10XL motor, MM, 66t spur, 18t pinion, UBEC, steel idler for 2nd gear. Will post better pics later, lookin better 'cos got it dirty finally :005:

BrianG · 11:33 PM

Yeah, I did mean that the motor actually makes the beeps, but of course the ESC sends it the signal to do so. If you have the motor not mechanically hooked up, you can see the shaft turn slightly when it beeps.

I read a little bit about why motors will do this and it said (can't remember where exactly) that the wires vibrate because of the frequency. If they are tighter winds, the noise sounds muted - like in a Neu motor where the coils are wrapped around some kind of core to concentrate the magnetic flux.

j-man · 05.03.2007, 08:32 AM

Final pics after first run, cleaned the wires a bit.

j-man · 05.27.2007, 05:21 PM

After cruising around with 12 cells, I moved to 7 cell packs, IB4200's. I've been testing them for a while now, on loose dirt, packed dirt, grass, and pavemet.
No matter what I do, the MM esc does not get varm, just slightly over body temps, batteries are a bit warm and motor 2 sec touchable.

More voltage? Does MM handle 15-16 cells, thats almost as much as 5s lipo, and I understand some problems with MM handling it? Or would the fact that nimh gives less amps help MM to handle it?

nieles · 05.27.2007, 05:27 PM

if you want a little more speed you can also gear up a bit in stead of adding more batteries.

BrianG · 05.27.2007, 05:29 PM

^^ +1.

The fact that the motor is quite warm compared to the ESC usually means it is a little undergeared.

j-man · 05.27.2007, 05:33 PM

I went to 20t pinion, 66t spur. 20t is biggest I can get from here, otherwise have to order from Mike, and ordering just one gear from 4000km away is... I'l have pile up an list worth ordering, just to compensate for the postage fees.

BrianG · 05.27.2007, 05:41 PM

I take it that 66T spur is the smallest? And judging from previous posts that you are using second gear?

It's not gonna be real cheap, but you could move to a Mod1 setup using the Strobe slipper. With the 51T Ofna spur, a 15T pinion will get you close to what ratio you are running now. So, you'd have some wiggle room as 14T and 16T pinions are available.

j-man · 05.27.2007, 05:52 PM

64 is smallest so not much improvement there. 51/15 or 16 might be an good choise.
And I would get an real slipper. Runnig diff balls in the spur right now. Works but not much slip...

Finnster · 07:16 PM

Quote:

Originally Posted by j-man

After cruising around with 12 cells, I moved to 7 cell packs, IB4200's. I've been testing them for a while now, on loose dirt, packed dirt, grass, and pavemet.
No matter what I do, the MM esc does not get varm, just slightly over body temps, batteries are a bit warm and motor 2 sec touchable.

More voltage? Does MM handle 15-16 cells, thats almost as much as 5s lipo, and I understand some problems with MM handling it? Or would the fact that nimh gives less amps help MM to handle it?

I ran my MM/8xl on 14, 15 then 16 cells last year during testing. It did it fine, but you are pushing it. 5S still has more power. I bought the 5S packs as my 1st lipo thinking it would be about the same 16 cells as it looks on paper... no...5S will rip your balls off (see my vid). So much punch and power...

The only prob w/ 16 cells is the fresh charge voltage is higher, ~1.45v/cell. It runs very close to the 25V rating of the caps. All in all I think a 4S setup is ideal for the MM. Lots of punch (more than 16 cells due to amp load) but not no high a voltage you are really pushing the ESC.

I had gearing @ 15/51 and 16/51 (for hi-speed stuff). Weight was 4.3kg (w/o batts) FYI