32" Mono Build

[Make-a-Wake]

Remmie, my Pursuit now has a 4082 2200kv and I'm spinning a..........................yep, you guessed it, m445! You are probably aware that the M series are the X series with the tongues removed. It allows the motor to rev out more.

http://www.offshoreelectrics.com/pro...?prod=oct-m545

[Remmie81]

thanks Guys!

Did a run yesterday (again with the carbon 42mm prop) .
Trimtabs were 1mm above bottom and it was doing already much better.
First run: stopped when I heard the revs going down: Lipo cells at 3.4 Volt, motor and ESC colt, battery warm
2nd Run: Stopped when I heard the revs going down: Lipo cells at 3,5 Volt, motor and ESC colt, battery hot

Driving time 4:00 min before revs dropping.

For the setup I have now, should I prop smaller? Like a 40mm prop?

It was a pretty small water, so had to go off the throttle and accelerate very often, could not make use of the full width of the channel
as there was a lot of debri in the water.
Here a short vid of the 1st run:

http://www.youtube.com/v/k7gTQqLel-k

[Bullwink]

Nice Build. I haver the same boat (Pursuit) Actually, the one Steveo built. After reading this post, I bought the adjustable stinger you have. So, now I have a couple of questions about it. What total length do you think is best and then, how do you secure it so it does not screw in or out?

[mtbenjamin77]

Nice Build. I haver the same boat (Pursuit) Actually, the one Steveo built. After reading this post, I bought the adjustable stinger you have. So, now I have a couple of questions about it. What total length do you think is best and then, how do you secure it so it does not screw in or out?

I have the same boat and stinger. You tighten the screw holding the angle adjuster that clamps around the stinger

[Bullwink]

Thanks! I just hadn't tightened it enough.

[srislash]

Hi Remmie,I just got my same hull as well.Just curious where you found that rudder?I have the same one on my cat but with a short standoff.Having interchangeable parts would be sweet.

Shawn

[siberianhusky]

You should be stopping when the voltage is about 3.7 resting voltage, you're taking the packs below 20% by going that low. One of the things I don't like about some esc's, too low a cut off voltage.
Timing your runs is the safest method, try about 3:30 and see how they do. It may not be your setup it may just that the batts are being discharged a bit too much.
One of the best buys I've made for electric boats is an EagleTree data logger, so nice being able to see exactly what is going on through the entire run. Sometimes it's a real eye opener.

[Remmie81]

Shwan, i got it from horracing.

@Syberianhusky
Ok you say 3.4volt rest is to low. Can you explain how you calculate the 20%
I dont understand how you get to the 3,7volt value.

Thanks!!!

[siberianhusky]

http://i703.photobucket.com/albums/ww39/filmmaker2009/Fuel.gif

This is from another thread last week about batteries.
Basically when you run a 5000mah pack down to 3.7 volts it takes about 4000mah to charge it again. That means you've used about 80% of the packs capacity during the run.
Your charger should be able to tell you how much went into the battery when the charge is done, you already know the capacity of the pack, the rest is simple math.
Hope this helps

[Remmie81]

Ah got it! Thanks! I was trying to figure out the 20% on the voltage.
Did 2 runs yesterday, stopped little bit earlier then last time.
Voltage was 3,7volt per cell on both packs.

Packs were warm but not hot. Temp outside was 30c so im happy with the result.

Put my gps in it: 53,5mph with the carbon 42mm

[Make-a-Wake]

Personally I consider 3.7v resting to be 100% depleted..................may not quite be but its darn close.

[Remmie81]

First lipo is on charger now. Will see how much amps it will load and that should give me
An indication of how far i pulled it empty with a rest voltage of
3,7 volt :-)

Thanks for all the information guys!!

[siberianhusky]

If 3.7 is empty why to I put 80% back into the pack?
But that is as low as I will run them, so you could in an offhand way claim that 20% remaining is depleted.
No point in confusing people with technically incorrect info.

[Remmie81]

So, both packs are charged. And like Siberianhusky said: at 3,7volt the pack is 80% discharged.
I run 5000mah packs and they both charged 4000mah.

Thanks again for the explanation!!!

[Remmie81]

I wanted to have the gap closed between transom and drive, so gave my buddy some measurements and he took that to his work and came back with this nice spacer.








After that I did my first run ever with this boat with a metal prop. Tried a X440/3