I need tips for building a 39" Mono

[Hyprsmash]

I am building a 39” mono and been looking at doing a 120amp Castle creations Hydra ESC. But the size of the boat do I want to go with the 240 Hydra instead? Also need help with motor choice. I would like to do a 15-21 motor just trying to balance out price and speed. Any ideas?

 

[Raydee]

I think you better look at a smaller hull. I don't think you will be able to get away with a 1521 or even a Hydra 240 in that size hull. I think the bare min that I would run in that hull would be a 1527 on 6s with a Hydra 180HV or 240HV controller. A better bet would be a 2215 series Neu motor but if you are on a budget you would be better off dropping to a 33" mono with a 1521 and Hydra 240 on 4s.

 

[jayt]

What do you want to do with the boat? Even for a sport boat that is a big hull for 6S - you'll need quite a few amps to keep it on step so run time will be reduced. Most guys running boats that size use 8S or 10S and set up for lower amp draws. With larger boats, using volts to get the required power is a much better idea because it is easier on the ESC and motor, and it gives much more run time.

I agree with Ray, unless you absolutely have to go with a huge hull you'd be better off with a smaller boat. My 33" Titan 40 runs great on 4S with a Castle 240, with a racing setup it runs 50 mph for a one mile heat of under 2 minutes - never ran it longer but judging by the capacity used up I could safely run for ~4 minutes with my 9000mAh packs as long as I could control the heat buildup.

You don't need a Neu motor for a sport boat - although there is certainly nothing wrong with one for that use. A Feigao 11XL or 12XL will give speeds near 40 mph on 4S propped to run for 5-7 minutes or more (depending on your battery capacity of course). You can use a Hydra 120 just fine - although I am always in favor of getting the most ESC you can afford. Remember too that run time and amp draw has a lot to do with how you run the model - keep it on step with wide turns and you'll run longer with less heat. Constantly accelerating and slowing down with sharp turns will burn up a lot of battery capacity, giving shorter run times and higher heat buildup.

.

 

[Hyprsmash]

I would like to get the most out of the boat without killing the old pocketbook. The mono is a fuller and I just went with the bigger boat. I found this motor on e-bay and was thinking about getting it. But if its not the right motor I will look at somthing else. Its a Q class and that is what I have been looking at on the Neu stite on what to use. I have linked the motor and found a esc 240 on e-bay as well. Thanks for all the help.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...E:X:RTQ:US:1123

http://www.neumotors.com/Site/Boat_motors.html

Feigao 11XL 12xl what size is this a 540 ?

 

[jayt]

It would be best if you answered the first question in my post - what do you want to do with the boat? Telling us that you "want the most out of the boat without killing the old pocketbook" is not at all helpful - I'm not trying to be difficult here, I'm trying to help. Are you trying to keep the total under $1000? Under $1500? It's all too relative so far. How much run time do you want? Is 40 mph okay or do you want 50? You could probably get 70 mph out of the boat in a SAW race setup - but how much is too much to spend to get there? Do you already have the good FM or 2.4 radio you should use with this big boat?

A 1521 Neu would be a decent choice for 6S - but NOT the one on eBay! There are nine different 1521 motors. I would suggest the 1521/1.5Y motor - it is efficient, powerful but not a race motor. It will turn the large prop needed for your big boat.

The budget 11XL is a large enough motor for 4S and limited 6S use, it is much longer than a '540'. In the big mono you would be better served with a gear drive and an 8XL or 9XL for good 6S performance with this sized motor.

The real limiting factor will be your LiPo packs - for both power and run time. All the power in an FE boat is in the cells not the motor - and small cheap cells will not give you speed or run time. Decide on what cells you can afford, then choose the motor and ESC.

Really, you have to define your own limits before you can build a satisfactory boat. I've seen too many boaters struggle to fulfill ill-defined goals by picking up parts because they are 'available' rather than what will best meet their goals. Most ended up broke and unhappy. Don't go there.

.

 

[Raydee]

http://www.offshoreelectrics.com/proddetai...?prod=fei-580-L

I wonder if something like this will work for him since he is on a budget.....I know the feeling.

 

[Hyprsmash]

I would like to race. I want to go 70 with this boat and do eveything the right way. Just want to get the best deal on the way there.

Steve

 

[drwayne]

I would like to race. I want to go 70 with this boat and do eveything the right way. Just want to get the best deal on the way there.

Steve

Ive a 33" on 6s1p that runs 60 but the cost is prohibitive for a larger hull... 70?.. thats a big ask for a budget build..... more weight, more drag, bigger batts, bigger esc, bigger motor, bigger bucks.

What's your budget ?

 

[Hyprsmash]

Well have about 600-800 to do right now. I am getting so much help for everyone I am having a hard time deciding what to buy. lol The Neu motors are really nice but they are double the price of all the other ones. The hydra line by CC looks like the right ESC but not sure if I need the HV or the standard 240. So I am still looking around. I really don’t need to go 70 I know but I do want to go fast and have fun with it...I have a Thunder cat by pro boat and it’s just too slow. lol At best I think it hits 33mph. The worst part is to get it to run I spend more time tuning they running.

 

[jayt]

With $800 to buy everything but the hull you'll not reach 70 mph. Most of that will go into the packs. For 6S you should use the Castle Hydra180HV controller - IMO you'll burn up the 240LV on 6S in a short time. Not much left over for the motor or hardware, etc.

If you lower your expectations a little - at least for awhile - you should get well into the 40s with decent run time and a lot of fun. I have no experience with either product, but the Feigao 580-12L that Ray suggested and the ETTI race controller sound promising, for under $300. That motor should spin a large enough prop to give decent performance with the big boat too.

A reliable 70 mph with a boat that size will run at least $1500-$2000.

J

 

[Hyprsmash]

Yeh, that sounds a little better. I will start looking at them. Thanks for all the help. Now what batteries should I be looking at for the 6s 11.1 X4 or something else?

 

[jayt]

Since the boat is large, I'd go for two 6S1P packs wired in parallel - if they fit. That configuration uses less wire for a lower impedence to protect the ESC. Minimum capacity per cell should be 3000 mAh, but 4000-5000 is better by giving longer run times and less stress on the cells.

.

 

[Hyprsmash]

I have been digging and this is the best price I can find. They are only 4000 but not sure if I need 20c 30c. What do you think?

http://www.hobbycity.com/hobbycity/store/u...?idProduct=7638

 

[Raydee]

I have been digging and this is the best price I can find. They are only 4000 but not sure if I need 20c 30c. What do you think?
http://www.hobbycity.com/hobbycity/store/u...?idProduct=7638

I would buy the Highest C rated batts you can afford. In my opinion the cells are not a place to skimp. You can buy a cheap chinese motor and esc and still have good performance but cheap cells in a boat will get you nowhere fast. BOATS ARE BRUTAL ON CELLS!

 

[drwayne]

I have been digging and this is the best price I can find. They are only 4000 but not sure if I need 20c 30c. What do you think?
http://www.hobbycity.com/hobbycity/store/u...?idProduct=7638

That 6S1P4000 20/30C battery is 80A output

The [ C rating ] X [ pack mAh ] is alleged output continuous in amps.

Always try to keep packs within that rating, as the peak C can be exaggerated .

Higher the continuous C rating, the more power you can safely draw from the pack.

Aim for the highest C your pocket can afford.

Better the batt, longer the run, more power to play.

 

[Hyprsmash]

Well guys, I went out and got a 33" delta force mono. I have attached some photos of it and had its first run this weekend. It’s the white number 36 boat. This was setup up by Ray Fuller and it ran really nice. I would like to get a little more speed out of it. What do you think?