Many thanks John.. I,m pretty sure that the 777 will ackle ok.. as there are a couple here with these motors fitted and they do go well with the correct combination of prop, and twin screw, twin motors 777.. I may well hold you to that statement John about the Brushless motors.. Thanks for the interest. Muddy....
It may be a transmitter/receiver problem or it may be in your drive setup that rears its ugly head once your on the water and your motor is under load. I had a similar problem with a twin motor setup which was fine out of the water but after 10 mins in the water I would lose drive to one or both props or one would slow down and just go round in circles (very embarrassing). I had no problem with radio setup so it had to be in the drive chain. I ended up changing both motors for ones with more armature poles, higher torque output and a different gear ratio. It also highlighted a problem with my first choice of battery which quite frankly were pants and used to produce similar symptoms as you describe. I now use Lipo power packs, they do have disadvantages but you can not knock the power to weight ratio. The main problem I was having appeared to be down to the 3 pole motors that were fine until they were under load, this caused the motors to overheat which in turn increases the current drain on the battery's, the net result is the motor starts to arch across the commutator and effectively becomes a dead short which in turn shuts down your ESC's or drains your battery's very quickly. As you probably know if this was to happen with Lipo's there would be no need for a smoke generator! Of course this only applies to brushed motors if you are using a brush-less motor then it will probably not help you.
quite a few years ago I was asked if I could make a model boat hull for a friends son. As then a laminator it was an easy job after making the plug to the approx specs asked for. I made the plug and mould then cast a test moulding asked if i could keep the test mould and was told by all means have one. The mould was handed over when completed and payment ect was made. The test moulding i just stuck in the loft Not knowing I would ever start modeling boats so much later in life. So Now I am into the model boats hobby. Here is the hull with twin outlets for the propshaft. And progress so far with the superstructure. Approx 51 inches long 17 inches wide and a depth of 11 inches. As I was paid to do the job nothing in the end belonged to me except the hull I was told I could have. In writing I may add.. Made a flat sheet of laminate and enclosed the whole hull on the top. Cut out an area for the superstructure and as you can see I have started a rough looking superstructure. I have no plans or drawings for this so it will go where ever it ends up I guess.. Apart from the hull I plan on using ALL recycled materials from our local tip. Paint .Plastic and everything else... The big idea apart from saving material from the tip is to make the model at the lowest possible cost. Motors and some other electrical parts will be removed and put into this model from the Ayton cross So all the parts will be transferable from model to model. Well thats the plan anyway. Guess I will have to wait and see how that goes later. Prop shafts props and rudders will be new so NOT replaceable. The timber so far a lump of 4x2 from the tip Free all cut down and sanded. The superstructure I have used a large fliptop plastic white bin from the tip again £1.00 Superglue bought from the local £1. shop. Filler and sanding paper I already have. So I have started it. I will update as I go along..
Hi guys need a little advice, I am finishing off a US Coast Guard Boat with twin props one left and one right handed, my question is if they are handed do the motors have to be wired up diferently i.e. One wired minus to plus and so on.
4ft model Riva Aquarama sports boat for sale, as featured in 'Model Boat' Sept. 2011. Mahogany build. Immaculate. Radio controlled. Twin electric motors. All batteries, controls etc. Hardly used due to bereavement. Based in Coventry UK. £300.
Hi Dave, good to hear from you (sorry to hijack thread). 4 footer came out two years ago, Huntsman once in 2016, Its over 3 years since the 3 footer got wet! Orca once in 2016. I did build the PCF which I really liked, but it went immediately as too many people messaged saying they wanted it, so it funded some RC plane gear, which I am really into now. I sold a load of bits and bobs at the Blackpool show a few months ago, didn't renew with St Helens in 2015, or 2016, and wont this year. However.... Robs excellent blog has got me interested again, and Stephen kindly did a bespoke 3 d printing project on something rc related, info and pics to follow when its finished! Back on track... George, I'm going to advise only things I have done, or used, I'm not one to say do this, or that, but actually I have not done it myself. No doubt others will disagree, but this is my opinion only. Best performance in terms of speed is brushless, and lipo. Forget fear of fire and explosions, this only happens with abuse, and they are the common use with rc planes, helicopters, cars, its only boats that are really stuck in the dark ages with technology that have this big fear of brushless systems and lipos! However, to get initially set up, they do take more understanding and initial cash outlay, as you need a specific charger for one, and you do need to understand what you are doing. Brushless motors will unlease the power far more than brushed, and are usually lighter. https://hobbyking.com/en_us/turnigy-t600-brushless-outrunner-for-600-heli-880kv.html This motor is an example, there are much cheaper ones with similar specs, but I have used this motor in various applications, the most similar to your boat being my large Huntsman, with this motor on 6 cells lipo I achieved 25mph, but speed might not be what you want. So if you have the fast engine in your car, say a v12 Ferrari, if you run it on cheap fuel, it wont perform, same here, nicads and nimhs batteries are easy to maintain, you can drain them dead flat, but will give cheap fuel performance, like a bath tap trickling when the shower is on at the same time, and as they are dying technology, are expensive for what they are. Lipo is like turning up both bath taps and the force floods out, but now the tank will empty quicker, so you have less run time 😊 If brushless, its a specific speed controller, https://hobbyking.com/en_us/hobbyking-50a-boat-esc-4a-ubec.html and you pay extra for reversing (other rc disciplines don't need reverse) and a marine esc might need to be water cooled, however, decent brushed motor speed controllers are not exactly cheap, so now you know why budget is important to give advice, you could be spending £100 here just to get up and running. Look at my 4 foot fireboat build blog, as its twin screw (personally a boat this size is better twin screw) you can get by with cheaper motors, mine where £30 the pair, I use lipo for all my boats, so I have the batteries, and are familiar with using them, the speed controllers where about £40 the pair, and if I was buying batts then probably another £40, so it all adds up! Single screw, less batteries. You could power with nimhs, and it might be acceptable ,performance for you. If your location is Ellesmere Port, have a Sunday morning drive to Hoylake, then New Brighton, and maybe take in St Helens Liverpool, and Runcorn, see boats in action, see what sort of performance suits you, and rethink the budget, what do you want to spend? Then you need the transmitter and receiver (if you don't already have these) the fittings (see Robs build blog) a prop shaft, and a suitable propeller I am North Wirral, you are more than welcome to come and have a chat and see some boats, but unfortunately I'm deep into another rc project for the next few weeks, once that is done I can share some time, if you want! Don't worry, I'm not all about speed, I can do brushed motors and nimhs and get a result, Any questions, just ask, Paul PS... Looks like a nice clean boat you have there😉
George, is it single or twin screw, and what is your budget, motor, speed controller, transmitter, receiver, batteries? Do youi want to go fast for say 20 mins, or plod for ages! Then I can advise...!👍 Paul
Hello Skegness..I am using 2 E-Max GT2820/7 brushless Motors. These Are UK purchased from BRC Hobbies (based Northolt) Cost £20.95 each.. these are 850 KV..using Twin Mystery RC 70A Forward Backward 2-7s Brushless ESC (with Ubecc) about £20 or less on EBay (HK). Run Time..1 Hour, mix of fast and slow Sailing..Depends on use. Using 2 X 7.2 NMH Volt Battery Packs..at 5000mah each. She Goes Like fast, and cuts through water lovely. Have A Similar Setup (Different Emax Motors) In my Models By Design Interceptor 42 Boat (42 inch length)..Tooo Fast for me..lol..Any Other Info PM me for phone number..Happy Sailing
Thanks for that. Mine is already fitted with twin shafts and a friend has suggested that I use two 900kv outrunners with 60amp esc's. I notice that you are using an Mtronics sound system, I assume for the motor sounds. What sound do you use as I understand that these boats were fitted with gas turbine engines?
[Score: 4/10] 40" ELCO 24 Capable of 8mph and a runtime of 20mins Twin Propellors (2 Blade S Type 35mm) Direct Drive to a 540 (2 Blade S Type) Powered by NiCad (7.2v) 3Amp/h Batteries Controlled Through Electronize (30Amps) ESC - Comments: Elco 24 was a up-scale of the Elco 32, approx 1/24th scale, Twin 540 motors but the performance was poor. This was never investigated and the project was shelved.
Hello Alan Permission to join this forum? Octman and I are old school friends and have been modelling on and off for 50 years. He and I have been trying, in vain so far, to use the mixer on my Spektrum DX6i. I am building an Aeronaut Pilot Boat which has twin brushed motors, which I would like to control with one stick and use the motors to assist turning at low speeds. The Spektrum instructions, which leave much to be desired and the many youtube videos, deal solely with aircraft, so I am struggling. Unless there is anyone out there that has programmed a DX6ifor this purpose, the description of your rudder mixer seems to be the ideal solution?
Hi Joe, just a few possibilities, is the tender completed? if not I would go for twin shafts with brushless motors, the hull where the shafts will go through would need reinforcing with 1/8 ply between the bulkheads to give the shafts some firm base to glue to and stop any distortion and fracturing of the hull floor. The motors I would suggest a pair of 30 / 40 size, most motors are intended for plane use so are often referred to in the engine size .30 ci, or .40ci, sound complicated but its not. As for radio gear, how far do you want to go!!! cheap bottom end gear starts at around £30 plus servos and speed controllers, as this is your first model, are you likely to build more???? if so I would go for higher speck gear, my choice is Futaba, but it is expensive, you are going to get lots of suggestions, have a look at the web sites and then buy what you fancy, (dont buy 2 or 3 channel, get a minimum of 6, this will allow for more functions as your modeling progresses) This is bound to though up loads more questions for you, dont be afraid to ask, mistakes can be expensive!!!! Regards Mark
HI Mate, there are so few pools to sail I/C boats these days it is just not worth the hassle. (Noise, possible pollution etc) As you are building from scratch, I would go for twin shafts, with big brushless motors, 60 size. if you have a look online there are a few places with them available, your area try the shop at Greenfield, north of prestatyn, or Steve Webb Models at Frodsham. With some 4s lipo's it should not cost that much either. PS big motors like your starter motor are way to heavy same as the battery, Hope this helps, Mark