My Impulse 31 misfortune

[de-pro]

So I have done a few mild mods since I got the boat. The most latest was installing a UL-1 motor and a very impressive cooling jacket I got from OSE.
Then I decided to to go with a hotter prop for this boat. After reading several threads and based on the availability, I ended up purchasing the sharpened and balanced X447 prop.
I installed the prop knowing I have to monitor the temps at the first few runs to make sure everything is ok. I started out with my older flightmax 5000 30C batteries I had kicking around. First off this prop made the boat go like a bat out of hell after a couple of minutes of run time I brought the boat in and checked for temps. ESC and motor were both around 100 degrees so was the battery. So that built some confidence in me and I changed the batteries to Gens Ace 5000 40C. Well I think that did the job, after running around a minute, the boat stopped. So we brought it in and immediately smelt the bad news
The ESC was done. The wires for the motor and the negative wire to the battery were just completely unsoldered from the board and sticking out of the ESC. Also burnt smell all over the boat and marks on the rear of the boat where ESC sat.
I guess I misjudged the fact the higher C rated battery can produce more current for the load on the motor. So much that ESC could no longer handle it. Thanks for a few tips on this forum, I cleaned up the Hull (although the sting is hard to get rid of) checked out the hull once clean and saw no visible damage. Please have a peak at the attached photo and tell me if it looks ok.
Also as a side note, I bought the upgraded trim tabs for the boat but I am having a hard time figuring out how to adjust it due to the design of the rear of the boat. Any advice on how I can work around it? I was thinking of making a small hole on the trim tab and turning the screw upside down. However I dont know what kind of effect the hole will have on the boat handling.
Thanks for reading and any advice you can provide.

[Racer944]

You have the right idea for the trim tabs... Darin Jordan showed this mod in his thread, and I did the same to mine... Here is a pic of my install.

Eric

P.S. Sorry to hear about the ESC...

Impulse 31 repaired trim tab screw and Speedmaster tabs 2.jpg

[Darin Jordan]

An X447 is a LOT of prop for a UL1 motor... especially on a Mono...

[martin]

You probably done the damage with that size prop rather than battery c rating.

[Fluid]

after a couple of minutes of run time I brought the boat in and checked for temps. ESC and motor were both around 100 degrees so was the battery....

This is hard to believe based on my experience with UL-1 motors in several hulls - none monos. What does "around 100" mean? Did you use a temp gun?

Most of us running that motor in P-Limited Hydros see higher temps with an x445 running two minutes in the summer, how it could be lower in a mono with more prop is surprising unless your Canadian water is ice cold. Did you let the motor and ESC cool down between runs? Like the others I believe the packs weren't the problem, the prop was just too big. Why you didn't see the problem coming after checking is surprising - sorry for the burndown.


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[de-pro]

Thanks for clarifying about the trim tab. Is there a hole made on the tab for the driver or just using a needle nose to turn the screw.
Darin, I am pretty new at this so I went for what was available at the time. I wanted it sharpened and balanced and its very hard to find those here. The UL-1 motor will be replaced by a Leopard 4074 2200Kv. I have lots of 2 cells and didnt want to get into lower kv higher voltage path. I also ordered the seaking 180 ESC. I hope this setup will be fine. I really loved that prop.
Martin, I know the the prop was behind all this but no damage was done when running the lower C rated battery. The reason the ESC died was because more current was fed to the motor through it by higher C rated battery. I gotta use the 70% load rule when pairing motors to ESC.

[de-pro]

100 degrees farenheit. I use a temp gun from my offroad vehicles. 1300 mah was taken from the flight max with no damage to ESC. Cooled down the escs and motor by injecting fresh supply of water and ran again. 600 mah into the new packs and she cooked.
I am actually not claiming any fault from the battery. Its fault was producing lots of juice to the motor as demanded by the bigger prop.
It has been cooler in here recently and the water temp should be in 70's where I go.

This is hard to believe based on my experience with UL-1 motors in several hulls - none monos. What does "around 100" mean? Did you use a temp gun?

Most of us running that motor in P-Limited Hydros see higher temps with an x445 running two minutes in the summer, how it could be lower in a mono with more prop is surprising unless your Canadian water is ice cold. Did you let the motor and ESC cool down between runs? Like the others I believe the packs weren't the problem, the prop was just too big. Why you didn't see the problem coming after checking is surprising - sorry for the burndown.


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[martin]

The point i was making was if you used the correct size prop then the higher c rating wouldnt blow the esc.

[de-pro]

No doubt. need for speed got the best of me and after seeing what that prop can do, then there is no going back to a mild setup :)
This is a great boat and has lots of potential. Like any RTR, the electronics are not meant for anything extreme.

The point i was making was if you used the correct size prop then the higher c rating wouldnt blow the esc.

[Racer944]

de-pro;

I drilled the hole in the tabs just large enough to get my allen driver through to turn the screw. I guess if you wanted to use needlenose pliars to turn the screw head, you could probably do so without drilling the hole... just flip the bolt over to make it easier to reach.

Eric

[de-pro]

Thanks Eric. Its appreciated

[Diesel6401]

The higher C rating did not cause the esc to fry, the size prop you used did. The higher the C rating the better when it comes to boating. The batteries only supply the amount of amps that the motor demands. Just because your batteries can put of more amps doesn't actually mean the extra amps are being used. The motor pulls the amps the esc recognizes the amp load and request that amount of amps from the batteries. Higher c rating didn't have anything to do with that. A x447 if a very LARGE prop especially on ul1 motor.

[de-pro]

Thank you. Is there a specific prop upgrade that is safer than x447? This motor and the replacement esc I got is going into a supervee.

[Diesel6401]

Thank you. Is there a specific prop upgrade that is safer than x447? This motor and the replacement esc I got is going into a supervee.

That motor is a very good choice for a SV27. I ran that ul1 motor in my sv with a grim 42x55 with great results..

[de-pro]

Thanks I will get one 42x55 on order. Please keep in mind I will still be using the stock 60amp esc

[Diesel6401]

Thanks I will get one 42x55 on order. Please keep in mind I will still be using the stock 60amp esc

60amp pb esc, ul1 motor and grim 42x55 is a good reliable setup in a sv27 on 4s. Make sure you have good packs.

[de-pro]

sure thing. thanks for the feed back

[Brushless55]

The higher C rating did not cause the esc to fry, the size prop you used did. The higher the C rating the better when it comes to boating. The batteries only supply the amount of amps that the motor demands. Just because your batteries can put of more amps doesn't actually mean the extra amps are being used. The motor pulls the amps the esc recognizes the amp load and request that amount of amps from the batteries. Higher c rating didn't have anything to do with that. A x447 if a very LARGE prop especially on ul1 motor.

I think this thinking comes from the traxxas fan boys?

But I am looking forward to the run in this hull on that big Leopard...

[burgerchow1]

You think your impulse had it hard, mine is like a timex watch. Takes a lickin but keeps on ticking. Was t-boned by another impulse, so missing a big chunk of the side ( patched up with hockey tape, but can still see fiberglass). Then I installed ul1 motor in it, got carried away at the pond and t-boned my pt 109 ( which my son was driving) at full speed. The whole front end of the impulse was lodged into the side of the pt109 about 8 inches deep. Pt109 is a write-off, but the impulse still works.
I think the impulse is indestructible. Awesome boat, almost as fun as my motley crew( when the motley crew is working)
I've also got the impulse 26 for my 4 yr old to run. Awesome boat for $160. The thing isn't super fast, but is as agile
As a tugboat, and a 2s lipo lasts a half hour with room to spare. great retrieval boat

[de-pro]

I'm glad your having fun with that boat...lol
Yes I only cooked the original ESC and mostly because I wanted more speed. Never had much luck with RTR electronics, not even in offroad vehicles. Also due to lack of experience I picked up the prop. But I tell you she flys with that prop.
Typically people buy prop based on their electronics, I bought electronics based on my prop....lol
So my leopard 4074 and seaking 180 are on their way. cant wait to try them out.

You think your impulse had it hard, mine is like a timex watch. Takes a lickin but keeps on ticking. Was t-boned by another impulse, so missing a big chunk of the side ( patched up with hockey tape, but can still see fiberglass). Then I installed ul1 motor in it, got carried away at the pond and t-boned my pt 109 ( which my son was driving) at full speed. The whole front end of the impulse was lodged into the side of the pt109 about 8 inches deep. Pt109 is a write-off, but the impulse still works.
I think the impulse is indestructible. Awesome boat, almost as fun as my motley crew( when the motley crew is working)
I've also got the impulse 26 for my 4 yr old to run. Awesome boat for $160. The thing isn't super fast, but is as agile
As a tugboat, and a 2s lipo lasts a half hour with room to spare. great retrieval boat

[de-pro]

So I finally got the new electronics. Leopard 4074 2200kv and Seaking 180 esc running on 4s1p. I will be trying the new setup this weekend. Going to try with the stock prop first then the x447. Before I do that, I just need to make sure I am not over-proping this beast. Any thoughts?

[Diesel6401]

So I finally got the new electronics. Leopard 4074 2200kv and Seaking 180 esc running on 4s1p. I will be trying the new setup this weekend. Going to try with the stock prop first then the x447. Before I do that, I just need to make sure I am not over-proping this beast. Any thoughts?

The setup is much more a 4s2p setup. I ran that same setup in a 32" mono and data logged 160amp+ spikes. I would not run that prop on 1p. I would prop down to a x442 or so until you get a 2p setup. That motor can pull some serious amps and your batts need to be up to the task. Get some batteries that can handle the load. Turnigy, Zippy, Sky Lipos, Blue Lipos, Gens Ace, TP, Hyperion have all been proven in boating.

[de-pro]

got some older flightmax 5000 30c (the light blue ones) and some newer dark blue ones, Turnigy 5000 30c and Gens Ace 5000 40c. More Gens Ace on order. Nothing 2p unless I use the two 4s in parallel

[Diesel6401]

got some older flightmax 5000 30c (the light blue ones) and some newer dark blue ones, Turnigy 5000 30c and Gens Ace 5000 40c. More Gens Ace on order. Nothing 2p unless I use the two 4s in parallel

Yea your gonna need two 4s packs or you can use four 2s pack in a series/parallel combination (that gets crowded though). You def need a 4s2p setup though with that prop or things may get ugly.... prop down until get a 2p setup!

[de-pro]

never been a huge fan of running two batteries in parallel. Tried it before and cells discharge wacky but worth the try. So your saying the Gens Ace 200 amp constant discharge wont cut it?
What speeds were you getting in your setup?
btw, cool Utube channel :)

[Diesel6401]

never been a huge fan of running two batteries in parallel. Tried it before and cells discharge wacky but worth the try. So your saying the Gens Ace 200 amp constant discharge wont cut it?
What speeds were you getting in your setup?
btw, cool Utube channel :)

Parallel is def benefical and is without a doubt needed in this situation. No I don't think the 200amp gens aces will cut it, i think they'll eventually puff and/or fail. I was running high 40s to low 50s with that x447 I then switched out to a m645 and started running mid 50s, but that prop heats things up fast. I really have to watch my runtime with that m645. I'm running two 4s 3600mah 30-40c turnigy batts in my Pursuit 32" mono, but i really should be running more like two 4000mah 40c/50c or something like that. My 7200mah 30C setup is getting worked. You need your batts to be able to supply A LOT of amps. I am prob gonna step down to a m445 and leave the m645 for when i feel the need to go all out. I am however running a leopard 4074 1774kv with a x447 on a 1p setup in a 29" cat. The fact the 1774kv has more torque and pulls less amps then my 2200kv motor and is in a smaller cat (my cat has less friction then the larger mono = less drag) allows to me run a 1p setup and i am running 6000mah 25/50 nano-techs in that setup with great results.

Thanks for youtube comment!

[de-pro]

Thanks for the great info. I dont have an x442 but have a 42x55 on order also can get my hands on an x642. Any thoughts?
All batteries puff a bit under load. the degree of it and how fast they go down will determine if they survive.

[Diesel6401]

Thanks for the great info. I dont have an x442 but have a 42x55 on order also can get my hands on an x642. Any thoughts?
All batteries puff a bit under load. the degree of it and how fast they go down will determine if they survive.

42x55 should work just fine on 4s1p. some puffing is related to how tight the shrink wrap is around the cells.

[de-pro]

Any thoughts on a x642? I picked one up from a friend

[Diesel6401]

Any thoughts on a x642? I picked one up from a friend

Should be fine, i wouldn't go any bigger on 1p.

Do you own a eagletree data logger? Awesome and must have tool for boaters!