Help - i really need some advise- conquest

[GRAEME LOUW]

I am trying to get electric boating going in South Africa as there are a lot of gassers here and I am the first person to start playing with proper electrics. I have a Aeromarine Conquest that had a Leopard 5698 - 910 kv motor with a 240 HV ESC running with a 452 prop and 10 cells and was getting 100 km/h from her. I wanted more speed so a bought 2 x TP Power 4092 - 1600 kv (4200 watts max watts ) running with 2 x Turgegy 180 ESCs and 6 cells Nanotech 45-90 batteries 5000 mah. Drive was through two stinger drives that I mounted right at the bottom in the middle of each sponson. Max speed is 77 km/h. So I removed the stingers and remounted them so that half the shaft was on the same plan as the bottom of each sponson. Speed no change at all. What am I doing wrong,as I live in South Africa and we cant get anything here so I have spent a fortune in boat motors etc
The two motors dont seem to rev as they should but are my stingers to blame. I cant believe that from a single set-up with less watts to a twin setup with more watts the speed can be so low
Please can somebody give me some advise
Thanking you
Graeme

[Fluid]

Twin motors is not the best way to get more speed IME, although twins can be very fast. Your single setup had an excessive Kv - members of my club get into the high-60s/low-70s with 10S boats running higher-quality motors with 750-800 Kv values and x462 to x465 props. Your budget 910 Kv motor could not swing a large enough prop to go much faster in that large hull. That said, your single setup seemed to be running about where it should given your choice of components.

I cannot say that about your twin setup since you have not told us about your propellers. Typically the stingers are mounted with the bottom of the stingers on the same plane as the sponsons bottoms, not hanging below the sponsons. I suspect that your prop pitch is too small to get the speeds you want. Too, your cat's attitude may not be optimum for top speeds with the twins. A photo of the transom would be helpful.


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[siberianhusky]

Smaller motors and smaller props. A given prop at 30 000 rpm is only going to move so much water so fast, thats your limiting factor.
If a prop is capable of pushing a boat at 50 mph at a certain rpm a pair of them will still only be capable of 50 mph at the same rpm. You suddenly aren't moving water through the prop at 100mph.
This is a very basic explanation , it's ignoring quite a few things but you should get the general idea.

[GRAEME LOUW]

Hi Guys
Thank you for the advise. I have tried x445 all the way to 450s with thec same results. Please can you let me know what motor do recommend for a single setup for a top speed of about 120-130 km/h. I will start all over again. I am from South Africa so everything I buy from the world must be x 8-5 USD to 13.5 fOR POUNDS and I have already waisted a lot on blown motors and ESCs. What do you think of Leopard ,TP Power and I see you can buy a motor that is adversised as 12000 watts for $100 with various KV ratings.
When I ran the Leopard 5698 - 910 kv on 10 cells I got 100 km/h but blew motor and the ESC 240 AMP and only when I contacted Leopard direct did they tell me max volts was 9 cells.
I was told to use 5- 10 cells by Fine Design and have had no response from them after buying the products from them.
What can you recommend for a reliable setup thats not too expensive for a 120-130 km Conquest. Prop , ESC

[drwayne]

Hi
I saw a comparison run between leopard and TP in same boat.... the leopard roared ... .
Leopard stated 9S to 910Kv as a limit to total rpm of around 35krpm.
That being said, I successfully run SF240HV on 12S to their 5692/730 ( 36500rpm ) to X665... your speeds were met. ( but you need extra caps between batts, esc and motor... )

This OSE website has a treasure trove store that delivers good products ( not a free advert... just fact )
Alternatively eBay can find 56xx leopards around $150USD from asia ( hobbyhot2010 just for eg ) .. but aftersales is a joke.

The TP motors at 12KW .. yes, Ive seen those .. find a marine hull large enough for the truckload of batteries you'd need, and ask again !

Fine Design have applauders and detractors. The great divide between the 2 groups is legendary.
Id check on this forum for previous discussions on FineDesign, for your own appraisal.

here is my Aeromarine cat twin (http://forums.offshoreelectrics.com/showthread.php?27178-Sprint-Cat40-twin)

cheers
Wayne

[siberianhusky]

Speed costs!
I have no experience with high voltage setups, but I do know that guys who are going fast with big setups are typically running Neu, Lehner and some Castle motors.
Do a search for similar sized setups and check out what guys who are running the speeds you want to run are using.
Sounds like you're having the typical Fine issues! LOL I got in touch with H&M in Germany so I wouldn't have to deal with him! Too many horror stories for this guy to risk his hard earned money.

[Make-a-Wake]

You went from roughly 36,000 rpms in the original setup to about 32,000 rpms in the twin, as Siberian pointed out. How do you expect it to go faster? The props can be larger due to the shared load. I hate to ask you to spend more money, but I think you need to try something in the Prather s240-s245 range, the are basically a 1.5 pitch and more diameter.

[GRAEME LOUW]

Wow you guys are fast !!!
Yes I have learnt about the fine experience !!!
If you were to give me a complete setup for the conquest for 120-130 km/h Would the Leopard 5692 / 98 be enough. Is the Neu 2215 a beter bet, but Neu states max Watts of 5000. This is slightly less than Leopard. I really cant afford to waste more dollars so I need to buy right this time. If it were you guys with all the experiance what would you go for from start to finish. From motor to prop as I really need as much info as possible
If you think the Neu will get my those speeds then I will buy from Steve.B I do have a Turgegy 240 amp HV ESC. Is that any good. All my batteries are Turnegy 45-90 C
Thank you so much for all the respose
Cheers
Graeme

[Fluid]

The Neu 2215/2Y is a great motor and would really pick up your performance. Another very good, high-quality motor is the Castle 2028. Both are much more efficient than the Leopards - don't believe what Leopard specs claim. A Castle 2028 just sold here on OSE for about $220 used, Steve is selling them for under $300 new. A club member used that motor in his Avenger and got 102 km/h with a small x455 prop. Running an x462 would put the speed in the mid-110s.



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[RaceMechaniX]

Here was my build thread about my Conquest.

http://forums.offshoreelectrics.com/showthread.php?12817-Aeromarine-Conquest-FE-Open-Cat-10S-Build

This is an excellent running cat for heat racing as does keep up with the gas boats. She runs about 72 mph for heat trim with an agreesive prop.

Tyler

[GRAEME LOUW]

Me Again. I dont think my last message sent last night was posted. Firstly thanks to all you guys for all the really great help and advise. I have taken your advise and will use a Neu motor from Steve but now do I go for the 1.5Y as you have used Tyler or DO I use the 2Y. My thinking is that 1.5 Y will give me about 38700 rpm on 10 cells and the 2Y about 28500 rpm on 10 cells. Is 10 cells enough ? 1.5 more RPM. Although I see Steve has no stock of the 1.5Y. Fluid you recommend the 2Y. My thought is that if I run 10 cells I can use the extra saved weight on mah for longer run times. Does this make any sense at all. What would be the very best ?
Would my Turgegy 240 hv ESC be enough or would I need to buy something else. I see Offshore has 240 Swordfish as well as 300 amp fully waterproof ESCs . Is this overkill

I need to buy right this time and not waste any more dollars. Even if I spend more now I just want a fast reliable set-up and you chaps seem to have got it ALL right
Thanks a lot
Cheers
Graeme

[GRAEME LOUW]

Another quick question.How is the Castle 2028 against the Neu 2215.
Will the Neu be quicker and more reliable ?
Does anyone have a Neu 2215 second hand for sale ?
Cheers
Graeme

[Make-a-Wake]

The 2028 is a fair bit more powerful than the 2215.......................probably 30-35% more if i had to pick a number.

[GRAEME LOUW]

A pic of my Conquest that was a single setup then the twin setup with TP Power and now I want to Neu it - PLEASE SEE PREVIOUS POST FOR PIC

[RaceMechaniX]

Graeme,

If you want the highest quality go for the Neu 2215 2Y or 2220 1.5Y. However the Castle 2028 is an excellent motor for the price. It works very well on 8S swinging gas props or 10S with smaller props.

Tyler

[GRAEME LOUW]

Hi Tyler
Thanks. Please tell me would a 1.5y or a 2Y be beter on 10 cells. I see Steve has no Neu 1.5 Y in stock. Would the Neu be faster than the Casltle - top speed. And is a 240 amp ESC enough or should I use the S Fish 300 amp.
Also what do you recommend What is the best a Swordfish 240 or the Etti 220 ESC. ?
Thank you so much
Cheers
Graeme

[Fluid]

The 2Y is a better 10S motor, as is the 2028. Otherwise you are in the same situation you were with your original setup - too high of a Kv. I would not expect much difference in top speed with either the Neu or Castle motors. You can go very fast with the 2Y, but you will over-tax cheap packs and ESCs with the 1.5Y if you try to push it. Here are some cheap Turnigy packs which were run in a 10S cat for a one-mile race heat; the motor Kv was around 750 with top speeds around 110.....

83541

[GRAEME LOUW]

Thanks Fluid
Ooch Those batteries sure look sick
I am using 45-90 C Nanotechs all round
Thanks for all the help !!
And is a 240 amp Turnegy and Swordfish ESCs enough. Are they not the same thing !!.Is the ETTI 220 amp a beter choice or do I go all out to the Swordfish 300 fully waterproof ESC. Or is this overkill !
HUGE DOLLARS !! For a South African at a EXCHANGE RATE OF 8.5 -1 ,BUT I WANT IT
Cheers
Graeme

[GRAEME LOUW]

Howzit Fluid
ME AGAIN .Sorry to bug but I have another Question
Would the Neu 2215 2Y RUNNING WITH 12 CELLS BE A BETER BET @ ABOUT 33000RPM than 10 cells @ 27750 rpm
I see the Neu can max at 55 volts and my rpm would be higher ie more speed. Am I correct in my logic.
How would the ESC hold out with 12 cells
I want to place my order with Steve but I want everything to be correct as I have wasted a lot on Chinese crap !,I also live about 3000km away from you so I cant mess up

Cheers
Graeme

[RaceMechaniX]

Graeme,

The 2215 2Y is a better 10S motor. The 1.5Y suits 8S better. The 2028 runs quite good on either 8S or 10S. And yes if possible run 2P.

I would not run the 2Y on 12S as you will be in the same situation as the 1.5Y on 10S. Too high an RPM to reliably prop.

TG

[siberianhusky]

You already stated the wattage of the motor, do the math and see what the numbers look like. You already know the potential amperage of the esc, you know the voltage of the packs. You've got all the info you need to figure out what your maximum potential wattage will be.
Basic electronics from grade 9, one of the first formulae you learn right after ohms law.

[Fluid]

I see the Neu can max at 55 volts and my rpm would be higher ie more speed. Am I correct in my logic.....You have to be careful using motor specs in that manner. The best way to calculate the voltage with a certain motor, or to pair a motor with a certain voltage, is to multiply the motor Kv times the nominal pack voltage. For most uses the result should be between 25,000 and 30,000 rpm. This will not be the actual rpm on the water under load, but it is a good general rule of thumb. The higher the calculated rpm value, the more difficult and risky it will be to prpo and run the boat. Some guys get by with values well above 30,000 rpm, but they are experienced and understand the risks involved.

You can achieve great speeds turning under 30,000 rpm by balancing the motor, prop and ESC so that you have good reliability. Heck, the gas guys get over 70 mph with that hull spinning well under 20,000 rpm. Tyler's advice is spot on.



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[GRAEME LOUW]

Thank you all
A final few questions before ordering. Please be patient as I am new into the FE Boating.
1 - Castle 2028 or the Neu 2215 2Y For 10 CELLS ( Is the savings worth buying Castle)
2 - What ESC Etti 220 ; Swordfish 240 ,Swordfish 300
3- What range of props do I order from Steve as I must bring in everything one time as we cant get much here in SA

Thanks
Graeme

[GRAEME LOUW]

Hi Guys
Please some answers to my last post
I really need to buy the goodies while there is stock at Offshore
Cheers
Graeme

[Fluid]

1 - Get the Castle. Cheaper, great performance and over a pound heavier than the Neu. The Conquest can use some weight to keep it on the water if you are looking for 120 km/h.

2 - I know nothing good about any of those controllers.

3 - The default general prop is the x462. If you want more speed and are willing to give up some run time you can try an x465, just be careful and watch the heat. An extra x462 could be detongued and pitched up too. For lower speeds an x457 or x460 will work.


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[lomdel]

Graeme, I am from SA as well, Bloemfontein. Been here on OSE for a looong time. If there is one guy to pay attention to, it's Fluid. He's been helping me a bit with my Thundercat 31 brushless conversion too in the past. I run a Feigao 11XL off 6S from a Etti 200A with a P210 prop. Got good speeds, but not SAW quality runs. To answer your questions regarding the ESC's, go for one that's programmable, like the Turnigy or Swordfish. The Etti programs with a lot of confusing beeps and blinking lights... That being said, powering an expensive Neu or Castle through cheap ESC's is not ideal. A castle 240A HV ESC is probably a better, although much more expensive option.

Good luck with this build, PM me if you would like to chat...

[GRAEME LOUW]

Hi Fluid and Lomdel
I have got so much good advise from this forum over the last week !
I have been flying rc planes and helis from a early age and got into electrics just after it started in SA .But the electric boats have screwed me. I have spent a fortune on motors ESCs etc and either can get the speed or blowing things up !!
I will order the Castle later today from Steve and all the other goodies.
My first attempt at FE boating was fron Fine Design and it was not pleasant and it cost me big dollars.
Lomdel, I see you are from Bloemies. Really great to see another South African on a US forum. I was born in Welcome and went to Saint Andrews school in Bloemfontein.
I now live in PE . I have licences for full size gliders as well as motor gliders
And in winter I live for my hunting
Cant wait to get my boat going again. Have to beat the gassers.
Cheers guys and thanks for all your time and advise
Chat soon
Cheers
Graeme