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1:12 BPB Whaleback advice requested please

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Big E:
Well, here we go, I've decided to build a 1:12 RAF 63' rescue launch, the wonderful Whaleback. It's been a long time since my last model (remember Hill two-valve receivers? Yes, that long!).  It was going to be a 34" Crash Tender kit until I called in and talked to Paul at P&S Models in York for some advice on motors. On the same weekend I also went to the Elvington Air Museum and saw a Whaleback model in one of their displays.  That settled it, why build a kit at 46" when you can scratch build something much bigger and with the added bonus of a yellow superstructure? Sold.
So, for the last couple of weeks I've been gathering info and reading everything I could find on British Power Boats.  I found Model Boat Mayhem and John WE (Bluebird's) brilliant article on building a Whaleback, then onto Martin13 in Oz and finally Todd Smith in the US. Poor old Todd has been answering my queries ever since!  The more I look, the more people offer help, information and suppliers.
I have a set of Pritchard plans on the way and I've now amassed quite a lot of photos (and a cd) so I am now almost at the point of no return and committing myself to cutting wood.
The reason for this note is to beg some advice please. My knowledge of electric power stopped at Taycol Supermarine specials, after playing with Taplin Twins and an impossible to start ED Racer.  I know the latest developments in Brushless offer amazing performance, but they have quite a few drawbacks for a novice, especially one who is a Mechanical Engineer and tends to treat electronics as black magic. I can cope with brushed motors, just about, so let's stick with those for the time being.
For a 63" high speed launch model I am proposing three CEM 900. Obviously I want it to plane, hence plenty of oomph. What are fellow members opinions of this choice please?  Overkill, or about right?
John WE alerted me to the problems of steering with three right hand props.  Do you think that a pair of out-turning props on the outer shafts and a right hand on the centre shaft, combined with preferential rudder control on the three rudders (Ackerman steering principle, like a car, sorry, don't know the correct nautical term) and perhaps an idling centre drive on turns, would overcome this?
John, thanks for giving me the inspiration to double diagonal plank, I just hope I can succeed.
Martin, thanks for your input via your article and Todd, just when I thought some models displayed amazing detail, you came along and blew my socks off.  Your turret frames are a work of art.
Final question: is a 1:12 scale model a bit over the top? We shall see!

essexbill:
I have always liked the whaleback, I did consider the Deans Marine a few years ago but, to do the boat justice the hull should be wood.
Looking forward to following your build.

Good luck 

raflaunches:
I don't think a 1/12 scale launch is too big!!!


My Dad and I have built four 1/12th scale launches used by the RAF Marine Craft Branch/Section but not a Whaleback. We have built a Walton 65ft ASRL prototype, a 60ft General Purpose Pinnace, a Thornycroft 62ft Fast Motor Boat, and a BPB 40ft Armoured Target Boat.
They are brilliant models in this scale as they behave much like the real boats but you will end up making a lot of the fittings yourself.
I look forward to your build.
For our source of power we use 12v Bosch car heater motors and 12v 7 or 10amp/hr SLA batteries, we also use prop shop (now Protean Design) cast Bronze propellers. On our three propellered model (Pinnace) we have used two RH and one LH props to keep the model in a straight line but he turns better in one direction obviously. Our LH and centre prop we driven by a belt drive from SHG Marine, it has worked really well and is still going strong 12 years later. Its a system we are so happy with that with my current project HMS Invincible I have two drive motors driving four propellers via a belt drive system.

Nordlys:
Big E ---- My collection of boats is made up almost entirely of RAF launches  - my biggest boat being the Range Safety launch at 46".
Personally I wouldn't choose anything larger than that because of weight and ease of transporting.
Just my opinion. -  but a great boat to build for sure.
Nordlys.

Big E:
Well, firstly thanks to everyone who has offered advice on suitable motors for the Whaleback. I'm still not decided on brushed v brushless, although I would prefer brushed (being very old and staid!) but I will persevere and let you know what happens over what might prove to be a very long build!
Thanks to RAFLAUNCHES for encouragement with 1:12 scale, your collection sounds wonderful. You mention Bosch heater motors and also gearboxes, but you don't mention prop sizes or shaft revs. Are you pulling huge torque on massive props or spinning like the proverbial? Also, do your boats (sorry, ships or launches. Submarines are boats, everything else is a target! I learned this working on nuclear subs.)......where was I.......do your models plane?
Thanks also to NORDLYS and I am tempted to agree, 63" models are perhaps a tad on the large side, but it's too late now, I've bought the wood, the equivalent of a mature forest, and I've built the board, so I feel committed. Hindsight is a wonderful thing.
STAVROS didn't beat about the bush - brushless and at least 15000 revs. Thanks for that, I am looking at the details of controllers etc. What do you think of Turnigy motors and marine ESCs?
Ah well, back to the garage and marking out the 17 frames.  Thanks again everybody, keep it coming.

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