Demagnetized...

[FloatDaBoat]

It's Shot - - the rotor should dang near jerk the wrench from your hand.

[Jeepers]

I agree the magnets are powerful!

[electric]

I wish I had a baseline for this, but it doesn't look good does it? So are they so powerful that it is kinda surprising how strong they are? My motor definitly feels about like a run of the mill magnet.

Regretably, it is all making sense. When I did the speed runs and propped up to a m445 the motor never even got hot. The amps never exceeded more than 129 (peak). Yet it got pretty warm when I was running just an x337(3 blade). Which would indicate the motor was failing.

I am at a loss as to why it failed? It never got to hot when I propped up, only when I propped DOWN to do some runs for time rather than speed? Odd.

Looks like a new motor AND a new esc.....

[Rumdog]

Being so underpropped, with a 37mm prop it probably wasn't loading the motor at all. Brushless motors require a load to run efficiently.

[TRUCKPULL]

Here is my last post from the other thread.
I think he over Watt'ed (AMP's) the motor.


Quote:
Originally Posted by electric View Post
Larry,
Here is the data from the previous runs..
Here are the stats.
8s / 28.8 volts , 12L 580 motor. 33" DF (knock off), 120HV Castle ESC
1st - x337 (3blade) 68amps
2nd - x337 70.55 amps, 2070wp, 30mph ( I moved the CG foward, ran wetter)
3rd - x442 101.34 amps, 3042wp, 44.7mph
4th - M445 - 129 amps, 3820wp, 38.4mph


5th run after all the HELP here.
M445 - 126.62 anps, 3727wp, 54.2mph! (The trim tabs got me a whopping 16mph!!!)...


First thing I see is the prop size is too small for the hull size and the weight (cells)
A 33 DF likes a larger prop
X447/3 blade or a X450/2 blade
For this you need a motor with lower KV.
Your motor is only rated for 1400 to 1800 Watts, which relates to 62 AMP MAX with 8S.
You are pushing 3500 Watts
You are using a 120HV and running a average 129Amp's
You should use a 240HV
You should always use a ESC rated almost twice the average AMP draw that you will run.

My "P"(4S) Mono (DF-33) set up for racing in my signature below runs faster then that in a straight line.

LARRY

[electric]

Larry,
Thanks for your input. The PEAK was 129amps not the average. I do have a question though, If I were to run a x447 or x450 wouldn't I be pulling huge amps running 8s? I was actually trying to run low amps with a high voltage in a (possibly misguided) attempt to run a set up that was fast, but cool(high voltage/low amps). Am I headed the wrong direction in my thinking on this?

Yeah, I do get the part about the Watts..that is quite a bit more than the motor was rated for. If I were trying to stick to the load (62amps) that the motor was rated for then the biggest prop I could put on was the x337 as it pulled 68amps.

I wish I had the speed/data on the last run I did with the x337 (after I got past the trim tab issue). The boat felt like it was flat out hauling. I was backing off the throttle to keep it under control.

Larry, given your experience, any guidence would be great and appreciated. Is it possible to go high voltage, low amperage and get good speed without the heat build up. Not to mention the longer run times that would come from that correct?

Rumdog - is it possible to under prop a motor and that would cause it damage? Trying to understand that also.

Since I am going to have to buy another motor and esc. Learning can be expensive. I am definitly going to get a higher amp esc. Still contemplating the motor though...

[Jeepers]

Here is my last post from the other thread.
I think he over Watt'ed (AMP's) the motor.


Quote:
Originally Posted by electric View Post
Larry,
Here is the data from the previous runs..
Here are the stats.
8s / 28.8 volts , 12L 580 motor. 33" DF (knock off), 120HV Castle ESC
1st - x337 (3blade) 68amps
2nd - x337 70.55 amps, 2070wp, 30mph ( I moved the CG foward, ran wetter)
3rd - x442 101.34 amps, 3042wp, 44.7mph
4th - M445 - 129 amps, 3820wp, 38.4mph


5th run after all the HELP here.
M445 - 126.62 anps, 3727wp, 54.2mph! (The trim tabs got me a whopping 16mph!!!)...


First thing I see is the prop size is too small for the hull size and the weight (cells)
A 33 DF likes a larger prop
X447/3 blade or a X450/2 blade
For this you need a motor with lower KV.
Your motor is only rated for 1400 to 1800 Watts, which relates to 62 AMP MAX with 8S.
You are pushing 3500 Watts
You are using a 120HV and running a average 129Amp's
You should use a 240HV
You should always use a ESC rated almost twice the average AMP draw that you will run.

My "P"(4S) Mono (DF-33) set up for racing in my signature below runs faster then that in a straight line.

LARRY

I agree with Larry ( I did not bother to read the other thread) and Larrys p mono probably uses less power and more reliable too, and cheaper (don"t need an HV controller) I still don't understand why people choose to run 6-8s in 33 inch hulls when 4s is MORE THAN enough, considering 4s is getting the same speeds if not better, especially in race trim.

[electric]

Just re-read your response Larry, you are saying I need a lower KV rated motor than than the 580 12? hmmm..That would make sense to swing the bigger prop, but then my rpm's would be moving to the low side.

[Brushless55]

Larry, what's your setup in your P Mono?
thanks

[Jeepers]

Larry, given your experience, any guidence would be great and appreciated. Is it possible to go high voltage, low amperage and get good speed without the heat build up. Not to mention the longer run times that would come from that correct?

its possible to do that on low voltage with good speed, propped correctly. especially if your not racing.

[Jeepers]

Larry, what's your setup in your P Mono?
thanks

I know and I am not tellin that sucker was FASSSST at the Nats!

[TRUCKPULL]

Larry, what's your setup in your P Mono?
thanks

It is not that big of a secret.
The secret is setup.
DF -33
4S2P -35C -5,000's Poly RC's (Enerland cells) =10,000 total
1521 -1.5D - 8mm shaft
3/16 cable
Hydra 240 (LV) with 4 extra caps added.
X447/3 blade
= about 120 to 140 AMP average draw
MAX run time about 3:00

You can see above my setup at 140 AMP's is about 2,000 Watts
For a 8S setup at 70 Amp's, you still need a motor that will take 2,000 Watts all day long.

Your best 8S motor would be a 1527 1.5Y for racing
or a 1527 2Y for sport
I would also recommend a larger hull, about 38' to 41" long.

Larry

[sailr]

Good to know Steven. Your reassurance is comforting. I'm just gonna run it and see what happens.

Why hope???
Sort of like "assuming". It hardly ever works. Take it apart and look.
Most likely its wrapped. And like I said before. MANY people are running these UNWRAPPED and have had great results.

[Steven Vaccaro]

Steven,
I pulled the back of the motor off and it slid out with some resistance, but not much at all. I did have the magnet attach to a wrench and it will stay attached even if I shake it a bit. I can take it off with very little pull. Hard to describe it accurately. I would say it comes off with maybe a very gentle pull.

What do you think? Anyone?

its dead, email me from the OSE contacts page about return instructions.

[electric]

Wow Steven. Thank You. That goes above and beyond good customer service!