Fine Design Racing

[Steven Vaccaro]

Sorry to hear about your issue. From reading some of the posts, 65mph should be attainable, but as they say the runtime is the issue. Besides the fact that you were told it would run for 15 minutes, is there another reason for wanting to run that long? You can also play with some formulas and calcs on this page to get an estimate on what capacity cells you would need to get to run that long
http://www.offshoreelectrics.com/conversion.htm

[Gary]

Look....there are so many things that could be wrong. I did the exact thing you did and called chris for his advice on building a 60+ mph hydro boat.He told me to up all the parts . Neu 1521 1.5d Hydra 240, and two 7.4 batts. Boat only could muster 45 mph. He told me to keep going bigger on props but it only hurt performance. Long storey short, boat now goes 74mph and i am betting on 76-78 or better for this Mondays SAW runs. My point is its the same motor...the same hydra, but more voltage, finding the perfect prop...after 8 i went through.. and changing the AOL on sponsons. Test, Test, Test ...look at it , ponder it, tweak it. I took my boat home every time and messed with something. So who knows mabe thats all you need to do.But above all the crashes , burnt up batteries and blow overs i LOVE to mess with it and make it faster.Hey....some people can put a boat togather and it runs like a champ. Others like me?............................. PS When you changed your prop you went from 47mph to 57 mph .....thats a 10mph change in a stock prop alone ...10mph!!!!!! See what i mean?

[kevinlew211]

In this video 2 x 2215 on 10S2P were used to get over 80 mph.

http://www.youtube.com/watch?v=i59znIXWmKw

Where did you get that info from???? that boat is not running twin 2215 on 10s2p, the reason i knew because i builded it.

[egneg]

Where did you get that info from???? that boat is not running twin 2215 on 10s2p, the reason i knew because i builded it.

You are absolutely correct - my bad. They are 1522's on 6S2P I went back and checked the thread from duncanjerry.

http://www.rumrunnerracing.com/feforums/showthread.php?t=26213

[midwestboat]

Well, just got back from my test run with 10S 2p. All 4 brand new identical packs. Ran 62.1 on GPS first run with a X465, Ran 58.2 with a X462. it is amazing who much weight is added by adding these extra packs. Run time was much better. Should I expect more speed as these batteries cycle a few times? Still not quite where I was told I would be but closer. Does not handle near as well with the X465 prop. First race is this sunday. Any suggestions please send them my way. Thanks

[HOTWATER]

A quick suggestion...more flotation! I know I'm on my soap box now, but don't hesitate to put extra flotation in and certainly don't forget to affix some to the hatch

I'm going to let some of the other more experienced guys provide additional input on the setup. Do you know what props you tried on it? To me, that prop looks small, but I don't have experience with the larger boats.

I agree with the prop being smallish, but look how thin and small the rudder is! I have an Aeromarine 20 cat and it has beefier hardware than that!!

Great looking boat though...hopefully you will get it to your liking!

[D. Newland]

LiPo's will typically get a little better after a few cycles, but don't count on much of a speed improvement.

IMO, if you don't have much tuning time between now and Sunday, run the X462 and keep it on the pins! Race water is different than test water so use the prop that is giving your boat better control.

Keep an eye on motor/esc/cell temps, time your runs and keep a record of how much MAH drain you are experiencing when running. Report back Monday. Good luck!

[midwestboat]

LiPo's will typically get a little better after a few cycles, but don't count on much of a speed improvement.

IMO, if you don't have much tuning time between now and Sunday, run the X462 and keep it on the pins! Race water is different than test water so use the prop that is giving your boat better control.

Keep an eye on motor/esc/cell temps, time your runs and keep a record of how much MAH drain you are experiencing when running. Report back Monday. Good luck!

Well, Saturday was cycling the Batteries and the Controller quit, smells burnt, Have a new one coming, Didn't get to race, Did get the boat to handle well with the X465. Batt temps where 104 to 107, motor was 170 one time and 204 the next. running between 63 and 65 pending on how wet I run. Am satisfied with the boat except for the failure. Chris said it isn't a "common" thing to have happen. Thought it was a thermo failure? next race 2 weeks.

[Brushless55]

Wow! 170-204* that's warm...
What were your esc temps durring these runs?
Sounds like you may be pushing your motor and esc to far.

[D. Newland]

Does the motor have a water cooling jacket on it?? Temps are high.

If not, check this site store for one.

I was out testing yesterday and there was a gas cat that radared 67 mph lap after lap. Everyone kept saying, "looks good all by itself, but it won't handle racewater!". Sure enough, the next time he went out for test laps there were 2 more gas boats out there. He ended up on his lid by lap 2.

You're getting good race speed out of that setup.

The Castle 240 HV's are good controllers and Castle will stand behind them, but I know of quite a few failures with them, too. With your 2P cells and large Neu motor, it's easy to see amp spikes that are 2 times (if not more) than your average amp draw. If you're drawing 140 amps on average (I don't know this, just using it as an example), it can spike to 300 amps in the turns, launching the boat, on/off throttle in chop, etc. I have found that driving style can help a controller handle the spikes better. I prefer a setup and speed that can handle full throttle 80% of a race, rather than varying/blipping the throttle all the time.

[midwestboat]

Wow! 170-204* that's warm...
What were your esc temps durring these runs?
Sounds like you may be pushing your motor and esc to far.

I didn't check the temp of the esc, it is watercooled and the motor is not. Chris told me 170 is normal, is this not the case. he did tell 204 was to high. He also reminded me my setup is for race only 6 laps and mill laps is it on the power I am running.

[midwestboat]

Does the motor have a water cooling jacket on it?? Temps are high.

If not, check this site store for one.

I was out testing yesterday and there was a gas cat that radared 67 mph lap after lap. Everyone kept saying, "looks good all by itself, but it won't handle racewater!". Sure enough, the next time he went out for test laps there were 2 more gas boats out there. He ended up on his lid by lap 2.

You're getting good race speed out of that setup.

The Castle 240 HV's are good controllers and Castle will stand behind them, but I know of quite a few failures with them, too. With your 2P cells and large Neu motor, it's easy to see amp spikes that are 2 times (if not more) than your average amp draw. If you're drawing 140 amps on average (I don't know this, just using it as an example), it can spike to 300 amps in the turns, launching the boat, on/off throttle in chop, etc. I have found that driving style can help a controller handle the spikes better. I prefer a setup and speed that can handle full throttle 80% of a race, rather than varying/blipping the throttle all the time.

Good to know, I didn't know you can't blip the throttle.

[Flying Scotsman]

Well, Saturday was cycling the Batteries and the Controller quit, smells burnt, Have a new one coming, Didn't get to race, Did get the boat to handle well with the X465. Batt temps where 104 to 107, motor was 170 one time and 204 the next. running between 63 and 65 pending on how wet I run. Am satisfied with the boat except for the failure. Chris said it isn't a "common" thing to have happen. Thought it was a thermo failure? next race 2 weeks.

This is interesting you battery temperatures are OK and confusing with your problems, your motor temperatures are off the wall. The ESC propabably failed as David mentioned due to low and off/on throttle input. Schulze 40-160 would be a better choice for that power and driving style. Is the hull running wet? Is the drivetrain free spinning without the motor connected? Why and how were you cycling the batteries? Are the bearings on the motor OK? What is the motor timing?

Douggie

[Doby]

FD built a boat without water cooling on the motor

Sorry not trying to make you feel bad, but apparently this is what they do for a living and to not include water cooling, even if its only built to run 6 laps is sheer stupidity.

I'll shut up now.

Maybe he thought he was building a truck, as that seems to be more their thing now.

[midwestboat]

This is interesting you battery temperatures are OK and confusing with your problems, your motor temperatures are off the wall. The ESC propabably failed as David mentioned due to low and off/on throttle input. Schulze 40-160 would be a better choice for that power and driving style. Is the hull running wet? Is the drivetrain free spinning without the motor connected? Why and how were you cycling the batteries? Are the bearings on the motor OK? What is the motor timing?

Douggie

Not running wet at all, Drivetrain is free, I was cycling the batteries because I had just recieved them the day before brand new. I thought it would be better to get a few charges in them before race day. I wasn't running hard just trying to run down the batteries. timing is stock. Not sure about the bearings, How do I check that? Motor has dozen runs on it. I am getting I should add a water cooler to the motor. Chris told me the Thermo? failed to shut down before failure? It is supposed to shut off for 20 sec and then restart? Dumb question. Should I be running full throttle as much of the time as I can? Does it hurt the boat to drive slow?