Shocker First Maiden Run -- ESC Literally BLOWS through Hull

[T.S.Davis]

Agreed. Especially with 38-42mm props. 30k rpm is the old way of thinking. Technoloy have moved forward, I'm not sure why people's thinking hasn't.

Because with many years of racing, thousands of laps, pushing the envelope, winning, setting records, and breaking some really expensive crap in the process........ we've learned a thing or two. Sure technology has advanced. You bet. Thank goodness. Wasn't that long ago we were maxed out at 70amps for a speedo. A thermal was a flame out. We've rode the train with the rest. However, physics hasn't changed. It's the great equalizer. The Q sport 2 lap record was set in the fall at less than 30000 rpm. Is that the old school way?

Let's do some quick make believe math.

I'm guessing the amps were over 180 but lets pretend that this setup was only 180 amps.

3.7(volts) x 6(cells) x 180 (amps) = 3996 watts. So that's 1.8 times the rating of the motor. That's of course assuming 100% efficiency.

What if it was only 150 amps. Still 3330 watts. 1.5 times the motors rating. Really? These are the setups you sport guys are recommending? This will burn up a less experienced guys stuff quick. Then they're out of the hobby. This I find frustrating.

42000 rpm are SAW numbers. SAW setups require more attention to detail than just slap it together and go. Something as simple as a grub screw sticking out too far can throw the drive off balance..........have some more amps with your amps. A drive dog that is square at the front.......more drag.......more amps. A water cooling pickup that doesn't appear as though it would pick up any water........no cooling.....so more heat...........which makes........wait for it........more amps. How about simply a thorough debur and polish of the flex cable? Should be done on a SAW boat. I buff mine on a polisher.

Put any of these together with a setup that's already likely past it's limits and you will have a failure. Little things are magnified at high RPM. You got it right or you got it on fire.

Who's taking the time to teach these little tid bits to a newer boater when you guys recommend these high RPM setups?

[dmitry100]

Ray, No i was not using the bec on the burnt ESC actually. The picture you saw with disconnected BEC is the burnt ESC.
BEC was on the one that survived. Are these motors any good? I sure hope its not the motor though.

What do you mean by your question "was the side that popped the side that was doing most of the turning?" ?

The picture of the burnt ESC is in the first post I made on top there. But here it is anyway:

Photo May 03, 3 21 14 PM.jpg

Photo May 03, 2 37 52 PM.jpg

[Spartanator]

why seaking changed the bulletproof design they had is mind boggling.

The V2 wasn't even waterproof. I had good luck with my pre-released SK180V3. The V2 had good cooling but need better engineering, the V3 models need some modifications as well (I have suggested a few as others have to.

Sucks that it blew up though.

[Luck as a Constant]

The V2 wasn't even waterproof. I had good luck with my pre-released SK180V3. The V2 had good cooling but need better engineering, the V3 models need some modifications as well (I have suggested a few as others have to.

Sucks that it blew up though.

Yeah I guess they both have their quirks.
No doubt it blows that it blew


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[iridebikes247]

I don't go by motor ratings. For example Lehner, Leopard and other manufacturers all have ratings that are WELL below what they can put out without failing. For example a Neu 1530 is rated at 4500 watts, which makes me chuckle because 8,000 watts can and will be drawn in an appropriate SAW setup, low temps too. Also Leopard rates their 5692 for 5500 watts, I've pulled 10,000+ no issues and most importantly not much heat. Lehners have their rating too but regularly people go well above the "stated output," in SAW and advanced sport setups.

Most SAW boats are incapable of oval at their top speed, most of the time is spent turning around or dropping off plane from a hard pass, taking a lot of stress off the components.

--Something got hot very very fast in your boat. Its pretty easy to rule out the drive line. If I were you I would get another esc, and start on lower voltage say 4s and do a bunch of passes, wide turns, etc. It should come back with nothing over 100 (even cooler but I don't want an argument).

[dmitry100]

Ray, what would you suggest to use to reinforce the hull... CF Cloth + Z-Poxy PT-40 would work ok (the ones found on kintecracing) ? Should I use some Expandable Marine Foam or anything to fill up the tips and seam in the front?

[dmitry100]

iridebikes247 -- I only have 4 x 3s 5000mah revo's. So I guess it won't hurt to give it a run with just 3s before and make sure the motor timing is set right... I have a feeling the guy that built the boat probably did not tune the timing correctly.

I believe the Driveline could have been a factor one of the factors here... as the flex was kind of at an angle that made the shaft spin kind of rough compared to the other side. So I loosened the motor mounts and afterwards the flex looked like it was spinning a lot more freely when I spun the prop by hand.

What range of motor timing would you guys suggest I should try out to be on the safe side?

[ray schrauwen]

What do you mean by your question "was the side that popped the side that was doing most of the turning?"

The side the burnt ESC was on, was this the side you made most of your turns on? As you turn with a twin, the inside motor is slowed down with drag while the other side is more 'loose', unloaded.

I have used Zpoxy and others such as MAS epoxy and West Systems. Zpoxy I think is more for finish than structure. Carbon fiber conforms to complex curves better than Kevlar and fiberglass conforms easier. If it was mine I'd use a quality epoxy and chopped CF or glass after trying to sand the area inside with sandpaper taped to a wood stick tool or whatever you can get in there to scuff it up and then clean out dust and wash with a solvent that will not hurt the hull.
Others have techniques more refined than mine

[iridebikes247]

I think the motors manual says you can run 8-10 degrees timing. I would start on the lower side and go up to 10 max.

--I rarely play with timing I just find out what others have done with my motor to esc combo as my setups are popular, your motors might be throwing the esc a curve ball if they're totally off from whats rec.

As far as the inlay goes its easy. There are a lot of epoxies out there I would make sure to get a good carbon fiber cloth. Keith Bradley has nice carbon, imo its the best to work with. Inlays can look good or turn to crap real quick Make sure to use a fresh pair of scissors when cutting.

I believe Keith did a tutorial on his site a few months back with a lot of detail showing how to do inlays.

[IRON-PAWW]

I think with experience, high quality parts, and money, it's possible to move into high KV setups. Again, with experience, it's possible to run such setups day in day out. SAW gets mentioned a lot. SAW is vastly different from a daily running sport setup though. Vastly different. There's no way on this planet I myself would go near anything SAW spec. Not interested in SAW mainly because there's just no SAW events where I am, and because I just don't have the right knowledge to go there. Like Clint Eastwood says - a man's got to know his limitations. If you're new to the hobby then SAW stuff is not for you - yet.

Getting into the art of running electric boats - my take is you should go conservative and setup very much within the established thinking - that being 1500 - 1600 kv on 6s. I've had boats go 100km/h (60 mph) on old school thinking and that's a guy with limited knowledge and limited money. Many have done a lot better than that.

Appears that twin setups change the classic way of thinking somewhat, because you have two motors assisting each other. But, others will need to assist there with recommndations because I really do reach my knowlegde limit on that score.

Timing. Motors are wound differently. D winds Y winds. The type of wind determines the best timing you should set. I'm hoping someone who remembers better than me can assist. :-).

[srislash]

Nobody thinks 1900kv is too much for 6s? Alrrrighty thennnnn. Burn em if ya got em I guess. Seems we have this kv discussion every spring.

1900kv on 6s is going to produce plenty of amps. If you were running at partial throttle the amperage would have been even higher. Then run it for multiple minutes that way? Amperage kills ESC. Sometimes before the thermal cutoff even has a chance to do it's thing. A simple stuff tube bend too tight could have blown the speedo. A burr on the stub.

I beat the crap out of my Seakings. I haven't been able to burn one.

Ok speaking from experience, one should not 'toss a new boat in the water' running this kind of setup. I do run 42,000rpm at the prop but it took me a full year of tweak and tune, temp and amp checking, and trying props and prop work to get it just right. This can get serious on the pocket book due to electronics or be it flight(boats make lousy airplanes).

[tlandauer]

I think with experience, high quality parts, and money, it's possible to move into high KV setups. Again, with experience, it's possible to run such setups day in day out. SAW gets mentioned a lot. SAW is vastly different from a daily running sport setup though. Vastly different. There's no way on this planet I myself would go near anything SAW spec. Not interested in SAW mainly because there's just no SAW events where I am, and because I just don't have the right knowledge to go there. Like Clint Eastwood says - a man's got to know his limitations. If you're new to the hobby then SAW stuff is not for you - yet.

Getting into the art of running electric boats - my take is you should go conservative and setup very much within the established thinking - that being 1500 - 1600 kv on 6s. I've had boats go 100km/h (60 mph) on old school thinking and that's a guy with limited knowledge and limited money. Many have done a lot better than that.

Appears that twin setups change the classic way of thinking somewhat, because you have two motors assisting each other. But, others will need to assist there with recommndations because I really do reach my knowlegde limit on that score.

Timing. Motors are wound differently. D winds Y winds. The type of wind determines the best timing you should set. I'm hoping someone who remembers better than me can assist. :-).

Ok speaking from experience, one should not 'toss a new boat in the water' running this kind of setup. I do run 42,000rpm at the prop but it took me a full year of tweak and tune, temp and amp checking, and trying props and prop work to get it just right. This can get serious on the pocket book due to electronics or be it flight(boats make lousy airplanes).

Well said.
I have been in this for four years and I still have not ventured into north of 35,000 rpm on a regular base. I don't have the patience and time to tweak things and I just want to run my boat for fun. However, I do know my limitations and so it is a rare occasion that I burn something up. Still, I have managed to burn two motors back to back because I had a hard time believing the advice I got from here.
My response here is not implying the OP's level of expertise but rather sharing my PERSONAL view on running set ups.

[kfxguy]

40-42k rpm is not "saw" territory.....anymore. Sorry. Let me give you some examples. The bj29, the impulse 31 just to mention two....have 1800 and 2000kv motors and the manufacter says it can run up to 6s. So let's do some pretend math here....bj29.....hmmmm... 22.2v x 2000kv = 44,400rpm. "Saw" right? How bout the impulse 31...... 1800kv x 22.2v = 39,960.

[rearwheelin]

Does it help to use some water pumps for this sort of thing, or is a good proper cooling flow sufficient most of the time?

Also, how do you guys suggest I repair those cracked seams in the front of the hull-- that the pressure from the burning ESC created? Perhaps it might be a good idea to lay an extra layer of CF.

Looking at how even sunlight seems to peak through soo easily... kind of scary what could happen if it ever hits a wave going like only 70mph.

Do I need to put down an entire 1-2 layers of CF everywhere, or just in the more vulnerable areas like seams, mounts, etc?
Which one of you has a how-to follow along about putting down CF inlays/reinforcement :)

Here is mine blowing up. @ 4:10 http://youtu.be/6E-YivMC1k0 Glad your ok I know that must have been pretty scary. The copper polymer heat absorbing compound that entombs the esc turns the thing into a bomb when something goes wrong . The worst thing you can do to a esc is full throttle from a stop ! My FG hull faired a bit better . It blew of the wood support in my hull. image.jpg

[dmitry100]

Do you guys know where I can get some extra water inlets that can screw into the heat sink of this Seaking 180 v3 ? I think it might be a good idea... to wrap the cooling line back around to the other side of it for better cooling.