Poof!!!!

[Rich]

Well I blew the second Etti 150..... The first was with a 580 6l on 6s, that one was self explanatory.

This is the set up.
Mean machine hull
Etti 150 esc no bec, and the big caps on ose
leopard 4074 2200Kv
X640
2 5s 5000mah 40c wired in parallel
Eagle tree logger
logged 57 mph ()
181.1 peak amps (I know its high, but I have run this many many times temps in the 115's)

So the question is, which esc should I get to replace it with? I was thinking the Swordfish 240 hv but I would like to know who has one and how well it works and if I should run the extra big caps on the esc?

[Rich]

Here is a pic of the damage, yes I had cooling fans above the caps worked well, but not when the fire started!

[Rumdog]

No esc will handle that abuse. Soryy. That's almost 2200kv on 6s. and 2200kv on 5s. You need a lower kv motor, or less cells. If you wanna go faster, prop up. a 40mm prop is small for a MM.

[Diesel6401]

A 580 6l on 6s is over 47K unloaded rpms and voer 48k on the leopard. Way way to high. Agreed with rum on this one. You need to stick to either 4s on the 2200kv motor and the 580 motor or drop down. If you want to run 6s get something around 1500kv.

I have a skunkcat which is similar in length to the MM at 29" and I run a Leopard 4074 1774kv motor on 4s with a CF48 prop. I working on sharpening & balancing my x447/3. I only use the Cf props for testing. I hit 47mph on a CF prop and only slightly more then 26k unloaded rpm. Click my video link in my signature. Higher KV and more RPM isn't always better.

[Jacked1]

Wouldn't that be like running an 8 pole outrunner at 24k rpm for the esc?
And i would agree that rpm is pretty high and really hard on the motor.

[Brushless55]

A 580 6l on 6s is over 47K unloaded rpms and voer 48k on the leopard. Way way to high. Agreed with rum on this one. You need to stick to either 4s on the 2200kv motor and the 580 motor or drop down. If you want to run 6s get something around 1500kv.

I have a skunkcat which is similar in length to the MM at 29" and I run a Leopard 4074 1774kv motor on 4s with a CF48 prop. I working on sharpening & balancing my x447/3. I only use the Cf props for testing. I hit 47mph on a CF prop and only slightly more then 26k unloaded rpm. Click my video link in my signature. Higher KV and more RPM isn't always better.

Maybe you and Rum can explain why the high rpms is hard on the esc?
cuz I have no clue

[Diesel6401]

I was trying to show him that you don't need a crazy amount rpm to obtain fast speeds, which is what I would imagine he is trying to do.

Only thing I could say is pushing a motor to it's RPM limit could led to a motor failure and we all know when a motor takes a crap their is a good chance the esc might go out with it. I think the Feigaos are rated for 50K unloaded not sure what the Leopards are rated for. I mean saw guys push the RPM limits all day. We all know im not the sharpest prop in the box, so I don't have a scientific answer for you, I just know over 40K rpm is a hell of a lot!

[Brushless55]

gotcha!

[Rich]

No esc will handle that abuse. Soryy. That's almost 2200kv on 6s. and 2200kv on 5s. You need a lower kv motor, or less cells. If you wanna go faster, prop up. a 40mm prop is small for a MM.

Rum, your saying go with a lower cell count and prop up? I believe it was Fluid that once said "Diameter means nothing, pitch means more" or something to that affect, not to mention he used an m440 on his mm to hit 60mph, anyway, hence why I am using a 40mm 1.6 pitch prop. With that being said I do want speed, I gained 5mph with the new packs I used on this run compared to the two venom 5s 3200s I was using, with the same setup. I understand high rpm small prop, low rpm big prop and low voltage big prop etc...
Do you think I could get the same 57mph + or - a few mph with 4s? I wish I knew how to take a screen shot of the graph from the logger, its very interesting where it started to go down hill.

Diesel6401, 47 isn't too bad but I want to hit a constant 55mph ish. I have a few larger props around that I'll try when I get it fixed.

the amp draw with an x640 and 4s with the leopard was peaking at around 130 to 140, that puts me at my limit right there.

That all being said, should i just go with a different esc then since the SF 240 hv is overkill?

[Diesel6401]

If I ran 5s I still would be at resonable rpm and I would run into the 50s easy and not be pushing the limits. Give the speed calc a try, it nailed my speed did on! http://www.offshoreelectrics.com/conversion.htm scroll down to the bottom.

The you picked Esc isn't over kill, its JMO that 2200kv on 5s/6s is overkill. Your boat your world though. I would just hate to see you burn out something else.

I bet if you ran that 2200kv on 4s with a m445 prop you would reach the speeds you want no problem. And not be pushing anything to the limits.

[Ub Hauled]

Maybe you and Rum can explain why the high rpms is hard on the esc?
cuz I have no clue

2200kv is a 4s motor, for starters...
the high kv motors will take away from the toque and torque will take away from kv... you cannot have both and expect low amp draw.
with high C packs in parallel 4s2p and a 2200kv motor should be fine for the ETTI 150 (and caps) to handle, keep the leads short and the water going...

more kv = less torque
more torque = less kv

based on that, the higher the kv, the more amps it will need to keep up with the same prop on a lower kv motor.

Diameter does matter... to a point. If you were to put a 2032 prop on the Mean Machine, do you think it would go anywhere other then back to the bench?
You need to find a happy balance between max pitch and max dia.

Here is a pic of the damage, yes I had cooling fans above the caps worked well, but not when the fire started!

FLASHBAAAAACKS!!!!!

[Diesel6401]

2200kv is a 4s motor, for starters...
the high kv motors will take away from the toque and torque will take away from kv... you cannot have both and expect low amp draw.
with high C packs in parallel 4s2p and a 2200kv

Thats what I run. 4s2p on that motor with a seaking 180 and a m445

[Brushless55]

now a CC1518 motor on 5s could whip this MM into shape at mid 50's or so right?
lower kv with more cells

[Rich]

If I ran 5s I still would be at resonable rpm and I would run into the 50s easy and not be pushing the limits. Give the speed calc a try, it nailed my speed did on! http://www.offshoreelectrics.com/conversion.htm scroll down to the bottom.

The you picked Esc isn't over kill, its JMO that 2200kv on 5s/6s is overkill. Your boat your world though. I would just hate to see you burn out something else.

I bet if you ran that 2200kv on 4s with a m445 prop you would reach the speeds you want no problem. And not be pushing anything to the limits.

I think i have an m445, ill have to give that a try, but i bet ill be pushing the limits with it though on 4s2p. I was looking at the sf 200 lv, has anyone tried that esc? I would put the huge caps on it.