Firstly John, thanks belatedly for a terrific account of your build of the 63' RAF Rescue Launch, the Whaleback. I should think you've just about forgotten it by now, whereas I have been thinking about it in detail for the last few weeks. On the strength of your article and the bottomless pit of information that seems to be available through Model Boat Mayhem, I have decided to attempt a 1:12 scale Whaleback, based on Mr.Pritchard's drawings, supplemented by all the photos and information I can get my hands on. If mine comes out even half as good as yours, I will be well pleased.
Taking your advice on deciding early on what motors to put in it and also having a go at planning required batteries and wiring, I wonder if you could give me some guidance please? (Here we go again; the age-old question, I bet you can guess what's coming. What motors?)
I have decided that brushless motors and their attendant electronics just isn't worth the hassle for a relative novice, so I think that three brushed 900 motors running on NiMh might be suitable, but others are suggesting three 700 motors, or even 800 or 850. Am I going for overkill here, would I be better off with 800 or 850 motors and what revs should I be looking for, 5000, 8500? 45mm props at three blade?
Action controls seem a very sensible choice (or as near as) and they have what looks like a perfect set up for three motors, but their circuit diagram for a Fairmile C is using 12 volt. Do I need to go to 24 volt? All I really want is to get the hull planing like the real thing, but I am totally stumped with prop sizes, revs and power requirements. Yes, I know, it is difficult to state hard and fast recommendations for any given model and I am not looking for a definite specification, but I would be very grateful for whatever guidance either you or anybody could offer with regard to at least a starting point, something which would be, as a minimum, powerful and fast enough.
Just one more question please. You mentioned in your write-up a small anomaly on the plans with reference to the beam measurement. I noticed this when the plans arrived today and so checked a copy of the original BPB General arrangement. This seems odd too! If the boat was 63' long and 17'-6" beam, is it worth scaling up the hull sections in relation to the overall length? The plans would give a 16'-3" beam.
Well, that's it for now, wish me luck trying to make 80mm diameter turret domes.
Thanks for any guidance you or anyone else might be able to offer and happy sailing.
Chris.
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Topic: Q & A - 63 FOOT RAF AIR SEA RESCUE LAUNCH by Bluebird (Read 76881 times)