Big Dee

Newbie Questions:
Recently picked up my first RC Boat, A Gas powered 26cc 54” Cat.

It’s a Dragon Hobby Saga Offshore
SPECIFICATIONS:
• Length - 1400mm
• Width - 380mm
• Weight - 6500g
• Propeller - D70xP1.2
• Motor - 26cc Petrol
I fitted a Spectrum radio and a couple of servos I still had on hand and after the first couple of runs and the thing shaking itself to pieces I have now screwed everything down with thread lock.
I still have a couple of areas I need a bit of assistance with

(1) The receiver power supply doesn’t last long, its running 4x1.v volt AA batteries. Can this be converted to a LiPo set up for longer running time and easer management? If so what size pack is recommended and how is the conversion done?

(2) When I start it (on a good running idle speed) and put it in the water it will stall unless I throttle it at the same time. This means the only way I can operate the Boat on my own is with the engine cover off so in can hold/carry the Boat with one hand and throttle the controller with the other hand.
(a) What if anything am I doing wrong?
(b) Can the auxiliary channel on the radio be used to increase the idle speed for lunching?
(c) Am I a complete idiot ?

(3) Electric onboard starts, are they any good? If so what's the best?

Apologies, but I am living in China and have no access to any hobby shops or anybody that can speak English for that matter.

Thanks in advance Big Dee

Justaddwata

My Feedback: (3)

Welcome to the forum (and hobby!!)

I cannot claim to be familiar with the Dragon Hobby cat though looking at a youtube clip of one it has some nice lines to it.

1 - I have not tried Lipo batteries for receivers. I have typically used a rechargeable hump pack which is 5x1.2v batteries or 6 volts and will last the better part of a day. The consideration is also that you use a quality battery. Using AA batteries in the holder should be plenty fine also (Use a cable tie or rubber band to ensure batteries to not jump out on you though!!) - but if you use a quality NiMH rechargable battery you will have a lot more hours of run time (and be able to recharge them too) But again - quality batteries last significantly longer than fakes or off brands. Perhaps a bit of a challenge in China as you dont have a lot of import batteries to chose from.
2 - Having to work the throttle while launching a boat is very common and a requirement for some styles of boat. A clutch is one option to make launching and retrieval a lot safer/easier - but a lot of work to install one in a RTR boat. You could also try turning up your idle speed on your transmitter as you are ready to launch but be sure to turn it back down when you have the transmitter in both hands so you can shut down the boat if you need to.
a) I would not say you are doing anything wrong - just need to find a way to hold the boat and radio at the same time (I can launch much larger cats while holding the radio alone).
b) it is possible to do something with the extra channel but to be honest you then run the risk of not being able to shut down the boat - plus you really should not need to use the extra channel for this option.
c) sounds like you are in the same boat so many of us have been in - it is a much harder hobby to learn when you do not have the benefit of others being around to help

3 - I have no experience with electric onboard starters - I think they are a bit unnecessary and might well be the source of more headaches than they could cure

No problem at all - it is part of the fun!! Was in China recently and am supposed to be there now - though the New Year holiday would have been difficult to work around. I can very much relate to the challenges you face. It is an incredible place!

jvdd

big Dee
I have one of these boat and it's a good fun boat.

you could also use Life battery or a good quality hump pack should last you the day.

The launching problem is because it is direct drive and as said before you could fit a clutch but they would require a lot of work.
The clutches work off centrifical force so when idling the prop is free until the revs build up and it will hookup the down side is a slight
reduction in performance.

I'd steer clear of the on board starters as they are very bulky and from what I've read seem very unreliable, also I don't think there is enough
room in your boat to fit it and it will affect the balance of the boat.

Jeanneau

Hi Big Dee
I had the same problem with the boat stalling. As I have got to know the engine and boat, I know that the engine needs about 1/4 throttle to not stall, so I start it at 1/4 throttle and leave it there, pick the boat up and chuck it in, lean back and grab the controller. This will only work if you have a ratchet radio rather than a sprung radio - I don't know what your is?

Big Dee

Well thank you all for your detailed reply’s much appreciated.
Well noted about the Hump packs and I will plan a trip toHong Kong in the next couple of weeks to see what I can find.
Judd: good to see another SAGA owner, have you made any modsor do you have plans in the near future?
Jeanneau: I am using a sprung trigger radio, I went that waybecause of my long history messing about with cars and trucks. I haven’t used astick radio for years.
I do have an unsprung stick 7 channel form a helicopter I havehere that I tried to fly once with an expensive ending. I have set it up on asmaller boat I have as my emergency push boat that I just can’t get the hangof.
Justaddwata: I have read a lot of your posts and have learnta lot and thank you for that.
I am in Zhongshan China so if you’re ever around let know.
Well I had an idea, this lunching thing was irritating mebecause I like to go use my boat early mornings but can’t without help unless Iran without the engine cover on. And the fact that I am a big guy and its noteasy to lower the boat from a dock.
I designed a simple hand clam that hopefully will allow meto not only lunch one handed but will also give me leverage to lower the boateasier.
I hope the below video uploaded (no expert with computersLOL)
Basically when the boat is on the stand I simply squeeze thetwo tubes together to open the clamp. Once the clamp is over the boat I releasethe bottom tube and the clamp under its own weight will cradle the boat. Then Ilift the top tube and the boat is clamped and carryable (is that a word?) byone hand and also gives me around 300mm more leverage. Once the boat is placed in the water I simplygrab the second lower tube and squeeze to release.
Works in theory but thus far its untested.
The first sample I have made is a little heavy but if works Iwill redesign a fully adjustable clamp in alloy.
Keep you posted on Saturday’s trial
Thanks Big Dee

http://youtu.be/r1vozjnomsA

Justaddwata

My Feedback: (3)

Have to say that clamp rig has to be one of the smartest ideas/designs I have seen in years. Great solution to the problem. Nicely done!

Hope you will post some videos of boat and launching rig in action soon!!