Returning modeller

Hi, I`m a new to this forum, 1st posting, so apologies if I get anything wrong.

After a number of years doing other modelling interests I`ve bought a boat back into the daylight with the hope of getting it up and running.

The model is a scratch build of Surfury, built from the Model Maker plan. Once built, I never got round to running it but I`d like to try and make that happen.

The motor ( already installed ) is a Graupner 700BB Turbo 9.6V 3307.. Controller is a Futaba Attack 2DR. Rudder servo is a Futaba S3003. Prop is a 2 blade Octura 45mm plastic one, direct drive from the motor.

This is where I`m now at a loss. With the passing of time , things have changed and battery technology especially so my problem now is,which type of battery to use. The boat at the moment weighs 2.6 kg. I`m not looking for high speed in particular, just something that would make it look reasonable on the water.

I`ve also got to get my head round connecting all the electrical side of things so will be taking a look in my other boat , a TID Tug to see how I put things together back in the day.

Hopefully I haven`t rambled on too much but I thought I`d ask about the power supply in the hope someone might have a suggestion .

Many thanks,

Jim.

hi there

I also built this model many moons ago. My version was I.C. powered by an Enya 19 glow. The problem with the Surfury model is that it was basically designed to go 'fast' in a straight line. It doesn't like cornering very well and anything below plaining speed - it is like a 'waddling duck' to say the least. I have plans to rebuild it some time in the future along with many other projects - but - I was thinking I may go for the brushless motors this time. What size, I am not sure yet. Also, I was going to go Lipo technology batteries - and this may be all new to yourself - but - if not - I would suggest this is the way you go for this type of hull.

If you are dead certain sticking with the original motor that you have - I would be inclined to go for NiCad technology 9.6 volt and something like 5000 mAh doubled up - giving you 10 amp for longer running time. Have a look on Component shops website under ACtion they can give you a good idea of what you require for speed controllers etc.

John

James. Welcome to the forum.

Slight flinger slip by John in that Nicads are now banned, and the current tech is Nimh (but he knows that of course!).

Certainly a 5000 mAhr one will be ok, doubling up will give you more endurance but they are heavy beasts so one should do at a time. Need to get a Nimh capable charger as well.

I know people are going to say that you should get a Lipo, but I think for your use a Nimh will be best (stand by for opposing views). A Lipo will of course be lighter and make it go faster... What battery does the tid tug use?? can there be crossover between models battery wise?

I also suggest that the prop might be a bit big? but only a test and the use of a watt meter will show you whats going on...(overloading motor or whatever)

Ashley

Thank you both for your replies and interesting information.

As the motor is already installed i`ll probably stick with that as a starting point. If things work when it eventually gets in the water and I can see how it performs I can then think about changes. Running this type of boat is all new to me.

Ashley, the T I D tug is powered by a six volt sealed battery and wouldn`t really fit in hull anyway so that`s a no no .

I`ve had good fun with the tug over the years. Just a thought, It`s ballasted with 20lb of lead and it`s got me wondering if I could substitute that for something else, as, if anything should happen , I wouldn`t be happy with that lead in the water.

I`ll follow up your suggestions regarding the electrical side of Surfury and see if I can put some pictures up.It might be a while as I`m not a computer wizard! I`ll have a look at the forum on the subject.

Many thanks gents,

Regards

Jim.

And thank you for the welcome.

Jim.

You could use the ligheter LiPo batteries but you will beed the right pack and the correct charger. They also need a bit more care and maintenance than NiMH batteries.

Colin

I think you may have trouble finding something as heavy as the lead to fit in the space in your tug. Gold would do it of course...

Sorry..I meant by the battery/tug question that the new Surfury batty might be able to be used in the tug as well. “Compact” or square formation packs can be obtained but the tug motor may not handle 10v or so. Obviously the lead batt is no good for a speedboat!

Ashley

Hi James

The Graupner Speed 700 series handle up to 14.4 volts, so you can use 3S (11.1 volt)Lipo batteries.

These charge up to 12.4 volts on full charge.

As to the TID a 2S(7.2 volt) Lipo would be OK.

Add some more ballast.

I find the Lipo's work great displacement hull and are easier to get in and out of small spaces.

A good balance charger and safety bag is required, plus a voltage which also tells you the battery voltage.

As for Speed controllers, I use the 60 Amp Hobbywing Quicrun which has simple link setting.

Harry Smith

Hi Harry. Nice summation!

Like the look of those esc, and as you obviously have no probs with them , will get a couple..cheap enough.

Ashley