RAF Crash Tender 46in - Posted: 4 years ago by michael1
HI this was my winter project the hull was given to me by my son who got It at a car boot sale It had been on fire as It was driven by a petrol engine In now has twin brushless motors with 45mm props but going to put 50mm props on when they come as It needs a little bit more speed Built from a set of plans this my first go at this as I build from kits In the past cabins made out of 3mm/1.5m ply and some 1.5mm balsa wood . Hull was sprayed and the deck and cabins brushed with enamel paint.
What ESC's are you using? Battery capacity? Do you know the max current your Thumbrun and ESC's can take? If possible I suggest you use a Wattmeter (a fellow club member may have one) to see what the position Is at the waters edge, this will be a worst case as the model will be stationary and drawing max amps. Brushless motors are power hungry and for max performance work best with LiPo's. Ideally the ESC should have a max rating greater (50%) than the max motor current. Unlike brushed ESC's lowering the throttle setting does not reduce the current flow but does Increase the heat generated. My experience Is brushed motors work best on smaller props. I suggest you check the heat of your setup after a short one circle run when you fit the new props. Look forward to hearing how you fare. Good luck 😀
I have to disagree when you say that brushless motors are power hungry I have one more boat on a brushless and get a longer run than with brush motors a lot of members In our club use brushless with good results
I agree brushless give excellent results and will outperform brushed motors any day, provided they are set up correctly. Power hungry was possibly a poor use of words. My point was that brushless electronics can and do draw very heavy currents which LiPo's are able to supply, and are very light weight. We use brushless on many model at my club and for performance and endurance they can't be beaten. 👍 😀
Just nearly finished my sea queen and had one outing and It did all I wanted. Scale speed and very plesed with It. Standard motor and 12 volt battery. It was last winters project but only just finished. My 1st motor boat as my others are sail.
Looking good. Glad to hear your early sail went well. I am In the process of restoring a Sea Queen and have just about managed to remove all the old coats of paint. As I am using a brushless motor and Lipo battery there Is ample space and I Intend to complete the cockpit detail. I see yours Is quite open, did you resource a particular style? I can't seem to find much In the way of detail, certainly not from the plan.
HI dave I am currently looking to finish the cockpit but the bits that came with the kit were a bit naff. I have put a shelf In and created a door frame to the cabin. I am looking to put steering wheel , morse control and Instruments ,maybe a seat. I will post some more pics when complete.
HI Roger Noticed the door and believe the captain probably stood but not sure If seats were fitted. Maybe I'll look at some full size cruisers for more detail. I have looked at other Sea Queens for Inspiration but this detail Is mainly lacking. I have seen a control type panel on one model placed to the right of the cockpit looking forward but at this scale quite a bit of detail should be shown. I will ask Malcolm Reade of Reade plastics If he has any Ideas as his dad was providing fittings during the Aeorkits period and he may have more details. I will keep you posted 😀
Will be pretty similar In both types as controls are fairly standard. Probably a compass and chart table If sea going. Malcolm Reade Is sending me some fittings so will advise further when received Cheers dave
Yes you right, I built one many moons ago It was my first model boat, cost me something like 30 to 35 shillings (£1.50 to £1.75), from the now long gone Ashton Model Shop back In the late '50s, not radio control, could only afford to run on a 4.5 volt cycle, but my pride and joy all the same. Looks like It had a slight conversion, or hatch Is missing behind pilots seats.
Yes, those models look to be reasonably original. Interestingly, there was only one hatch - the one at the stern. When I complete my long-mothballed Sea Hornet, I'll probably make up a second hatch to cover the engine compartment. How's your progress? Tim.
Yes you'd be right to put a hatch behind first row of seats, that's where motor access hatch was originally, not second row seats as In your model. It original only had two set of bench seats, each behind their own window screens.
Cannot remember what happened to my "Hornet", maybe It went the same way as my CorgI and Dingy toy car, kindly given away by my Mother In my teens, whilst I was In the RAF, thought I finished with them, women they don't understand us fellows :-)
I've just launched my latest model a RAF Fire Launch pictures on this site, still some way to go, fire monitors etc, turned out to be very responsive and quick, once fitted 50amp controller and tweaked blades. Peter47
The wheel chair motor was no good at all. very low revs and negligable thrust. Fitted a replacement Johnson motor from a 14v battery drill, ......success!......reasonable pace semI planing for about 15 mins when the motor gave up In a cloud of smoke.
I have been given a motor stamped Johnson 970 with a label 'Marlin MK2'. The motor has 1/4 shaft and runs at considerable revs on 12V and has been used In a model cabin cruiser on 14V.
My prop Is a 3 bladed brass 50mm. I think this prop was too much for the original motor and caused the burnout. Would the bigger Johnson handle the 50mm prop or should I fit a smaller prop?
A 50mm prop Is a sizeable Item, for a setup requiring "speed". I would either suggest you use a gearbox and drop It to a 3:1 setup, thus offloading the motor, but tripling the torque out. Why not simply fit a medium size brushless motor, which will give you the revs you need and drop to a smaller prop. this then allows you to use a smaller/lighter battery pack [Lipo].
I dare say that If you check the spec on the "johnson" motors, you wont be getting much more than 16 - 18,000 tops at Its top rating. dont forget, this Is In "unloaded" test.
Coupling It to a 50mm prop, you would be lucky to see any more than about 400 rpm, BUT a current draw In excess of the motor rating, thats why It did not last long.
Well fellas, Sucess the boat performed pretty well, similar performance to the motor which burnt out, but without any drama. Checked the temperature of the motor occasionally, and It seemed warm but not excessive. The battery Is a 7amp lead acid (Motorbike type) and gave well over an hour running time. Unusual feature of the boat, Is that being big (46") the wash Is considerable.
Not Strictly Aerokits!!! Bought this and a Sea Breeze at the Warwick Show. Sea Breeze Is In the cupboard for Xmas. Sea Nymph Is Ivory and Brunswick Green. It has a JP 400 motor with an Mtroniks 15 amp esc powered by a 7.2v nicad. Currently It has a 35mm S prop. Haven't had a chance to try It out on the water yet. Maybe this weekend. Its the first wooden boat I've ever built so am quite pleased with the outcome. Looking forward to the Sea Breeze as that's going to be my first brushless model.
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Aerokits Fast Patrol Boat - Posted: 6 years ago by jelley_baby
HI Two Pictures Before and After, As Purchased on Ebay and Now ready to sail. First sail 16-12-2012 Cwmbran. First fitted a too powerful Outrunner with a small rudder no good would not steer or go straight. so changed outrunner to a lower rated one about 1200 kVA and fitted a larger rudder (medium size as opposed to a small one). The result was very good and she ran all morning on a 2 x 4.8 Volt 3800 MAh Nimh In series 9.6V total, for about 2 hours.
Hi, I'm currently in the process of building my first model. It's one of my fathers that has been sat in the loft, kit form for 30 odd years. I have the decals to turn it into a fire boat but I'm struggling to find a suitable monitor to place on the coach house roof. Can you remember where yours came from?
Hi, it's not a proper monitor on the cabin roof, but the spray nozzle from an air freshener the type that are battery powered and spray one burst every 15 minutes. I suppose that you could attach a small pipe to it and make it into a working monitor if you wanted too. Hope that this helps Graham.👍
Assuming Its about 36" long a nice speed 600 should give a good turn of speed. Prop about 35-45mm. You will need to have room for the batteries, probably NiMh's, plus the radio and ESC (25 amps?). If you are Into brushless and LiPo's you will really motor, but there Is a cost to set this up Initially. You will also need to carefully check the propshaft and bearing for wear - IC engines are not kind to the running gear. Good luck with the restoration 😀