All donations are securely managed through PayPal. Amounts donated are not published online.
Many thanks for your kind support.
Model Boats Website Team
March 2018: 9 people February 2018: 8 people January 2018: 25 people December 2017: 7 people November 2017: 13 people October 2017: 9 people September 2017: 15 people August 2017: 10 people July 2017: 4 people
What your asking for is possible but not easy. A 12V ESC will handle an overvoltage but I cannot say how much and depending upon the current draw of your motor a voltage regulator can be expensive. The simple solution is to get a 3s LIPO However you do need a special charger and have to make sure you do not discharge a LIPO to too lower voltage. https://www.rchelicopterfun.com/rc-lipo-batteries.html if your interested in going LIPO have a read about the care and feeding of them.
just cut a slot in the transom and move the tiller inside the boat. If your worried about water make a compartment to contain any water that enters. The design attempts to reduce the possibility of water entering via the rudder tube.
if the tiller arm is exposed you can either use a closed loop and hide the servo or accept your going to see a control arm and pushrod for a simpler install. Other than that it works what exactly are the problems you have?
I have to agree with jarvo remember the original boat was intended to have an IC engine and the radio control of the 1960s. Transistors were in use and the radio gear while it was bulky was not that heavy. Personally I would recommend you remove all of your batteries and stick in a decent 3cell LIPO. Where are you trying to ballast your boat down to? The originals ran with little if any extra ballast purist would say they were over scale speed but you have a throttle stick.
do a test run in the bathtub you can leave the superstructure off and use the throttle while holding the boat in place make sure you wife is out so the bathroom has time to dry out afterwards. Give it a run and see how hot the motor gets. The 850 is specified such that your prop should be fine. Please remember to include a locknut otherwise if you select reverse your prop could unscrew while sailing and you may lose the prop. Let us all know how you get along and enjoy .
Your original motor was a 650 and you had it over propped so its current draw was way to high so it burned out because it couldn't spin fast enough. The 850 is a MUCH more powerful motor and should be able to handle a 50mm prop. The 850 will spin faster so less current drawn ( I know that seems counter intuitive but its how it works) Your boat will probably go faster but you can throttle back to get the speed you want.
before you start ripping out your prop shaft an 850 should be able to use your existing prop. Specifications of 800 and 850 Overall length 110mm (4.3/8’’) - Width (inc. fixing plate) 50mm (2’’) - Weight 585g (20.6OZ) - Voltage 12v DC (reversible by reversing polarity) - RPM for 800 (no load) 5100 & for 850 (no load) 9778 - Current consumption for 800 (no load) 1 amp- maximum efficiency 5.3amps-suggested maximum continuous 7 amps-current consumption stalled 28amps and for the 850 Current consumption 1.9amp (no load) - maximum efficiency 10.8 amps - suggested maximum continuous 13 amps - current consumption stalled 40 amps - Suggested prop size for both motors: 45,50,55 & 62mm in 2 blade nylon or equivalent 3 blade brass
before you fit a water cooling system try a smaller prop. You need to think of the gearbox in a car. Too big a prop can be looked at as being like trying to drive off in top gear! A smaller prop will allow any given motor to spin faster and strange as it may seem use LESS not more current. If you keep the drawn current down to the limits set by the motor constructor then its probable you will need no extra cooling. If the boat moves faster than you want use the throttle its what its for. Throttling down also extends battery life. The air intakes on boats like this were intended for IC engines and they NEED air to work.
I had a quick look around and discovered this hull matched 12V 750 Speed electric motor, hull matched 40mm 2 bladed prop this from http://www.cornwallmodelboats.co.uk/acatalog/aerokits-sea-co... However if you want performance http://www.kingslynnmodelshop.co.uk/Motors_and_Speed_Control... That should give the equivalent power output to a .40 IC engine and make the hull come to life the way it was intended to. Couple that to a LIPO battery and a suitable ESC. Remember when the kit was originally made IC was the norm The Sea Commander was introduced by Aerokits at Gorleston Norfolk in the early 1950s. Designed by L J Rowell the Sea Commander is a smaller version of the Sea Queen. The length is 34 1/4 inches by 10 3/4 inches and is almost identical except there is no mast. Intended for the ED Marine Racer and Hunter power plants
the scoop should be fitted behind the prop so prop wash is driving water through it whenever the motor is running and the cooling coil fits around the motor join the two up with fuel tube etc. then the other end of the coil connect to an outlet ( unless you want a self filling boat) http://www.cornwallmodelboats.co.uk/acatalog/cooling-coils.h...http://www.cornwallmodelboats.co.uk/cgi-bin/sh000029.pl?REFP... As to sitting on your boat you could put it in the water and get some one to hold it while you run the motor up and watch the current used. closing off the cooling vents to an electric motor not used in a speed model shouldn't be any problem if you have the correct prop an electric motor should only get hand warm. The temps you indicate would have burned out your motor even if there had been no covering over the motor at all. With an electric ( brushed) motor the more you load it the higher the current flow and the hotter it gets. Stall current tend towards infinity you have what I think is a 60mm prop and that's a BIG prop being 3 bladed makes the situation worse since there is increased blade area against a 2 bladed prop. If you intend to use that prop then get a motor man enough to swing it.
At the risk of being repetitive get yourself a watt meter that way you can see how much current your motor is drawing. If a motor overheats you are either running to high a voltage or to big a prop. If you are intending to push the envelope you can buy a cooling coil to fit over your brushed ( or inrunner brushless) motor and use a water scoop thus water cooling your setup.
Your problem is interesting me one other thought is:- when the boat is out of the water the loading ( current) is way lower than the same motors in the water. It may be possible that the increased current is causing the voltage to " sag" and thus cause all sorts of strange effects. One simple thing you could try is to remove the red lead from the ESC(s) and power the receiver from its own battery. That's the red lead to the RX not the ones to the battery. If you can use a watt meter to read the battery voltage and current draw with the boat in the water.
On the face of it its impossible however since it occurs we must accept reality. So brushed motors how is the suppression? Your statement about nothing connected to the water metal prop shafts and tubes? metal rudder shaft and tube? If you have a multimeter see if one of your prop shafts has a voltage. It has to be some effect of conduction and the prop shafts are the obvious conduit.
it depends how much work and thought your willing to put in but for anyone with a bent for such things an arduino can " read" RC signals and with a suitable add on board control servos so should also be able to control ESCs thus you can tailor the drive to your requirements including the forward on one drive and reverse on the other for tight turns.
put a watt meter on your shopping list please. They are not expensive and will give you an informed idea of the current drawn etc. Remember LIPO batteries should not be discharged below around 3.3V per cell else they DIE.
As an afterthought when you have rubbed down with wet and dry used wet wash the paintwork off well allow to dry and then use a lint free cloth to make sure all the old paint dust is gone. Make sure you work over a surface you do not mind being marked since the drips from rubbing down make an excellent paint on an absorbent surface!! ( yes I made the mistake so I KNOW). Its a very messy process but well worth the effort.