Titan 33 Build

[riverman]

Just starting out with an empty Titan 33 hull. Based upon answers over in the General section, I have been doing due diligence with the OSE formulas to get an initial take on motor/battery combos.

Target speed - 50 to 55 (Fluid says they start heading for the tops of pine trees at much over that)

Looking at the Leopards on the OSE site, I focused on the 3674, 4074, 4082.

Given the wattage and subsequent current draws, I believe the 3674 is too low (1000/1500 watts, 69/104 amps - not enough torque) and the 4082 a bit too "large" (2000/3500 watts, 108/189 amps - probably more than enough torque but needing a huge esc and not getting good run times) If I am mistaken - let me know

Given the 4074 ( 1500/2000 watts, 81/108 amps)as the motor of choice (or an equivalent if you have one) my question now is would you go with:

(all mph come from OSE formula with 1.4 at 42, 45, 47 props)

2 5s with 4074 at 2000 KV (loaded rpm 31450 - mph 52,55,58)

or

2 6s with 4074 at 1650 KV (loaded rpm 31135 - mph 51,55,57)

Given a 5000 mah battery, estimated run times with 2's is 7.4 continuous, 5.6 burst

More Questions:

Is the 4074 sufficient for this size boat (given my speed objective)

Which setup is best for heat build up? Motor, battery, esc?

Can the 4074 handle larger props(pitch/diameter) Will it handle the 1.4 42/45/47?

Given the 4074 burst wattage/amps draw (as determined above would you go with a 120 or 160 esc? What manufacturer?

Thanks in advance for the help and advice in getting this boat running in the water.

[srislash]

A castle 1515(4074) would be a good match as well. But I think you are on the right track. A 120 is a tad small especially for a 47mm prop.

Had to tune in for this build. I like these hulls and have a 32" Bling build going right now myself.
Shawn

[rickwess]

I've been going through the same due diligence on my Insane 34 build. Here's where I'm heading:

• TP 4060 5D
• SF 220A Pro+ ESC
• 4s2p 5000mAh each

With 5s2p and 6s2p you're adding a lot more weight to the boat. You can scale back the mAh capacity to save weight since they are more efficient than 4s, but then what have you really gained?

[Fluid]

Given the wattage and subsequent current draws, I believe the 3674 is too low (1000/1500 watts, 69/104 amps - not enough torque) and the 4082 a bit too "large" (2000/3500 watts, 108/189 amps - probably more than enough torque but needing a huge esc and not getting good run times) If I am mistaken - let me know...Given the 4074 ( 1500/2000 watts, 81/108 amps)as the motor of choice (or an equivalent if you have one)....

The 4074 motor is too small for the Titan 40 hull. I'd not use a smaller motor than the 4082, there is apparently a misunderstanding of motor specs. The 4082 specs are not what the motor will draw, but what it can safely handle. You don't have to load the motor to those specs. Trying to get 50+ mph from the 4074 motor will lead to disappointment due to inadequate torque and inadequate motor mass to handle the heat. On 5S you will be pulling at least 135 amps to go 50+ mph, and amp spikes will be higher.

If you want both speed and run time, I'd go with 6S and either the 4082 or 4092 motors with a Kv around 1200 to 1400. You will get much more run time than with 4S at the same speed, things will run cooler and you will have the option for a few 'SAW runs' if you ever want to. Believe me, the extra weight of 6S is nothing to the Titan. In rough water I add up to one pound of lead to mine, and all that does is help keep it on the water - speed remains the same.


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[srislash]

I believe he has a 33" hull there Jay. ;-)

[Fluid]

I believe that Aeromarine (the manufacturer) calls their hull the Titan 40. It measures 33" long and is nicknamed by some the Titan 33.


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[srislash]

I believe that Aeromarine (the manufacturer) calls their hull the Titan 40. It measures 33" long and is nicknamed by some the Titan 33.


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Ahh, one of toes nitro references then

[riverman]

The 4074 motor is too small for the Titan 40 hull. I'd not use a smaller motor than the 4082, there is apparently a misunderstanding of motor specs. The 4082 specs are not what the motor will draw, but what it can safely handle. You don't have to load the motor to those specs. Trying to get 50+ mph from the 4074 motor will lead to disappointment due to inadequate torque and inadequate motor mass to handle the heat. On 5S you will be pulling at least 135 amps to go 50+ mph, and amp spikes will be higher.

If you want both speed and run time, I'd go with 6S and either the 4082 or 4092 motors with a Kv around 1200 to 1400. You will get much more run time than with 4S at the same speed, things will run cooler and you will have the option for a few 'SAW runs' if you ever want to. Believe me, the extra weight of 6S is nothing to the Titan. In rough water I add up to one pound of lead to mine, and all that does is help keep it on the water - speed remains the same.


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So if i do the 4082 (2000/3500 watts, which is 108/189 amps max the motor can handle) then I would size the esc at about 220? You were also suggesting the 1200 - 1400 kv motor. I had originally specd out the 1600 which gives loaded rpm as 30200 and the mph as 51/53/55 for the 1.4 props of 42/45/47. Once i get going, what would you expect a ballpark figure to be for wattage/amp draw given the 6s and say a 47 prop? Then I can figure out a ballpark run time.

If I went 4092 given the same setup (except for perhaps a larger esc) would this motor draw about the same amps running as the 4082 (which would give eqivalent run time)

Thanks - learning a lot.

[Fluid]

That hull will need to average about 2500 watts to do 50+ mph. On 6S that's ~120 amps, give or take. I'd use a 180 amp ESC capable of 6S. It isn't the motor size which determines the amps (within limits), it's the load you put on the motor - the prop and how freely the hull runs. You don't need a larger ESC just because you run the larger motor - as long as you control the load (amps). The larger motor works less hard and handles heat much better...unless you stress it with large props and try for 65+ mph.....

An x547 should work very well for you once you get the boat sorted out. Your run time will depend on how you run - plan on mostly full throttle to save the ESC. Use prop size/pitch to reduce the speed, not part-throttle.


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[Fluid]

Ahh, one of toes nitro references then

Uh, it is a nitro hull. I strongly recommend that anyone who races a Titan 40 - or who will run one in rough water - get the full nitro layup with the stringers. Not only does this add strength and make the build virtually bulletproof, it makes it easier to install most of the components solidly. Put the motor in the back and the packs between the stringers. I've blown mine off while runing well over 50 mph several times - with zero damage.

The boat can certainly be built without the stringers - my old carbon fiber Titan is still racing with short motor mounts glued in. The club member who owns it is the fifth owner of that hull!


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[srislash]

These must be good and sturdy then. Out of curiosity anybody got a hull weight? Just looking for comparison to my equivelent size hull. Thanks

[riverman]

I have an older hull I believe that does not have the newer carbon fiber insert bottom. It does have the stringers. Anything I should do with the hull before installing anything?

Would you do the 4082 or the 4092? or at this size, doesn't make much difference?

1600 KV vs 1400 KV?

Thanks again.

[Fluid]

Mine doesn't have the carbon bottom - doesn't need it, don't add it unless you just like the looks. I have a Neu 1521 in mine which is equivalent to a Leo 4092. The cost difference between the 4082 and the 4092 is small, I'd go for the 4092. As for the Kv, this isn't a hydroplane. To go 54 mph in my Titan I spin 27,000 rpm with an x450 with a 1850 Kv motor on 4S. On 6S all you'll need is a Kv around 1300/1400. With the 1600 Kv motor and you'll be more limited in prop size if run time is important to you.


My Titan with 4S2P/5000 packs weighs 9.5 pounds and is perfect for the rougher water we race on - although you can still blow it off if you're not careful with the throttle.

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[riverman]

Fluid, you absolutely going to regret ever getting involved here. I need some more education . (also I think for others who are following)

First since you are running the same boat and you have real world data (vs theoretical formula data) I'll go with the 1400.

I would like your insight on using your setup and inputting those numbers into the OSE formulas, (it gives a 43 "top speed"). What do you believe the formula doesn't take into account that makes the difference? Also interested in your comment "it isn't a hydroplane". The hydroplane has less wetted area than a mono and therefore would go faster with same setup? Your statement implies to me that you would need more kv to get the speed. Please educate.

By the way what would it take for us to get you to transplant to North Carolina?

Thanks again.

[Fluid]

Fluid, you absolutely going to regret ever getting involved here.

No I won't, I do what I can to help those who actually want help. However I leave for Europe today and may have spotty Internet connections for the next week.

I would like your insight on using your setup and inputting those numbers into the OSE formulas, (it gives a 43 "top speed"). What do you believe the formula doesn't take into account that makes the difference?

When I input 1400 Kv, 6S, 70mm of pitch (y547) and 25% slip it gives 54 mph, about what I'd expect.

Also interested in your comment "it isn't a hydroplane". The hydroplane has less wetted area than a mono and therefore would go faster with same setup?

Hydroplanes can use motors with higher Kvs than cats or monos for the same power level. 1600+ Kvs are more appropriate for hydroplanes than monos IME.

By the way what would it take for us to get you to transplant to North Carolina?

An extra twenty years of life expectancy......