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[dmn1]

Hi Boat builders, As a complete beginner on sailing my model boats, i could due with some info on how to make my Graupner Azimut Atlantic Challenger go faster & stay on the water longer!.
I have fitted the boat with two Graupner 700BB Neodym Turbo motors 9.6 volt, these are direct drive to props.
At the present time im using 2x 6volt 4.5A lead acid batteries linked together to give me 12 volt running.
Any info would be most helpfull, i have also built a model called Moonraker which has three of the above motors & also running on 12volts.
Regards Dave.

[nick_75au]

Hi Dave,

Probably the easiest way to get your boats faster is to increase the voltage to the motors and/or reduce the weight, A clubmember at our club got his Moonraker really moving by running a combination of 4 and 5 cell Li-po batteries to suit the two different 700 motors, two  9.6V and an 8.4V for the Booster jet.

The same thing for the Challenger, Li-po would be an excellent solution.

Now for the bad news, unless you have had experience with model electric flight and these batteries (you say your a beginner model boater)  there is a steep learning curve in using these batteries, they have the potential to be dangerous. They have fairly stringent parameters for their use. Its not too complicated but a mistake will cause damage to the batteries or worse. Not that other forms of batteries are safer, they if abused also have some danger

This is a very good guide to Li-po, its long but worth reading
http://www.rchelicopterfun.com/rc-lipo-batteries.html

If you feel the effort for Li-po is too much then Ni-mh batteries would be a big improvement over the SLA batteries, they are more tolerant of misuse, have a higher discharge rate so even a slightly lower mAH capacity Ni-mh will give you longer run times than the SLA and they are lighter for the same capacity.

Cheers
Nick

[Stavros]

Personally I would change the motors and fit some 900 motors water cool them and run on 24v for each motor using Nimh packs  and 55mm 2 bladed props this set up should give you a decent running time and going like a train


Dave

[dmn1]

Hi Nick, Many thanks for the usefull info, boats going much faster on nimh batteries.
Im studying the web site you sent me on understanding batteries it is a lot to reading but well worth the time.
Will be fitting Li-po batteries soon now i have more knowledge about batteries.
Regards.
Dave.     

[nick_75au]

Glad to help

Cheers
Nick

[red181]

those neo motors are very good, and very tolerant of "upping" the voltage, I ran one in a 36" crash tender for a while, on 2 x 9.6v nimh packs, it was very good, but needed water cooling. Graupner motors state a voltage, but also a voltage range, for speed tgry and get up to the top end of this, but the run time will decrease, its a play off, short run, but fast! long run, slower!

Totally agree with nick's post, lipos will get it shifting, but require maintenance. I would stick with minhs till your experience is better, as you can run them flat, you cant run a lipo flat. One thing though, that neo motor is a bit amp hungry, make sure you are using decent connectors on the batteries otherwise they will get hot